Nanotechnology based drug delivery systems for the treatment of anterior segment eye diseases

Aminated fullerene for comprehensive dry eye therapy: Promoting epithelial-barrier reconstruction and nerve regeneration by suppressing oxidation and inflammation

Dry eye disease (DED) affects up to 50 % of the global population, leading to serious discomforts that affect patients' quality of life. In the multifactorial etiology of DED, oxidative stress is at the core, initiating a sequence of inflammatory responses and surface damage via a vicious cycle. However, current therapies merely have a narrow focus on inflammation. In this study, we developed a novel antioxidative eye drop, ethylenediamine (EDA)-modified C70 fullerene derivatives (abbreviated as FN-EDA), to break this vicious cycle. FN-EDA was successfully synthesized by modifying C70 fullerene with multiple ethylenediamine (EDA) groups, resulting in enhanced water solubility and a positive charge. This modification significantly improved ocular surface retention time, cellular uptake, and lysosomal escape in vitro. Therapeutically, FN-EDA significantly alleviated dry eye disease (DED) in a mouse model. It reduced corneal epithelial damage by 3.8-fold compared to 0.05 % cyclosporine A (CsA) and restored tear secretion to approximately 65 % of the normal level. Mechanistically, both in vivo and in vitro results demonstrate that FN-EDA is endowed with superior biological activity in effectively scavenging excessive oxidative stress, down-regulating proinflammatory cytokines expression, and promoting epithelial barrier reconstruction, even recovering corneal innervation. Thus, our findings open an avenue to make this multi-functional eye drop a promising candidate for DED.

An overview of novel formulations for ocular viral infections: focused on nanomedicines

Ocular viral infections are a common cause of blindness globally. Many ocular viral infections are mistakenly identified as bacterial infections. In these situations, treatment is initiated belatedly and fails to address the root cause of the infection, which frequently results in serious ocular complications like corneal infiltrates, conjunctival scarring, and decreased visual acuity. The efficacy of conventional treatments for viral infections suffers from poor bioavailability, which requires the development of novel methods of drug delivery, accurate diagnosis, and efficient treatment choices. As nanotechnology in medicine advances at a rapid pace, multifunctional nanosystems are being prioritized more and more to address the problems brought on by viral infections of the eyes offering targeted delivery, increased bioavailability and decreased systemic toxicity. This study delivers a thorough overview of the use of nanomedicines in the treatment of ocular viral infections, with a particular emphasis on how they may enhance the safety and efficacy of antiviral drugs. We address a range of nanocarrier systems, such as liposomes, nanoparticles, nanosuspension, proniosomes, in-situ gels, dendrimers, and nanogels, emphasizing their distinct characteristics that facilitate the effective transportation of antiviral drugs to ocular tissues. This article also highlighted the regulatory barriers of ocular nanoformulation. The transition of in-vitro studies to in-vivo and clinical models has been discussed. This review also highlights the Preclinical studies of ocular viral treatment, ocular nanotoxicology and advancement of ocular antiviral treatments in the form of patents, ongoing clinical trials and marketed formulations.

Recent updates on drug delivery approaches for improved ocular delivery with an insight into nanostructured drug delivery carriers for anterior and posterior segment disorders

Ocular diseases have a major impact on patient's vision and quality of life, with approximately 2.2 billion people have visual impairment worldwide according to the findings from the World Health Organization (WHO). The eye is a complex organ with unique morphology and physiology consisting of numerous ocular barriers which hinders the entry of exogenous substances and impedes drug absorption. This in turn has a substantial impact on effective drug delivery to treat ocular diseases, especially intraocular disorders which has consistently presented a challenge to eye care professionals. The most common method of delivering medications to the eye is topical instillation of eye drops. Although this approach is a viable option for treating many ocular diseases remains a major challenge for the effective treatment of posterior ocular conditions. Up till now, incessant efforts have been committed to design innovative drug delivery systems with the hopes of potential clinical application. Modern developments in nanocarrier's technology present a potential chance to overcome these obstacles by enabling targeted delivery of the loaded medication to the eyes with improved solubility, delayed release, higher penetration and increased retention. This review covers the anatomy of eye with associated ocular barriers, ocular diseases and administration routes. In addition it primarily focuses on the latest progress and contemporary applications of ophthalmic formulations providing specific insight on nanostructured drug delivery carriers reported over the past 5 years highlighting their values in achieving efficient ocular drug delivery to both anterior and posterior segments. Most importantly, we outlined in this review the macro and nanotechnology based ophthalmic drug formulations that are being patented or marketed so far for treating ocular diseases. Finally, based on current trends and therapeutic concepts, we highlighted the challenges faced by novel ocular drug delivery systems and provided prospective future developments for further research in these directions. We hope that this review will serve as a source of motivation and ideas for formulation scientists in improving the design of innovative ophthalmic formulations.

Iontophoresis impact on corneal properties using an ex vivo bovine eye model

This study addresses the challenge of low drug bioavailability in topical ocular administration by developing and validating an ex vivo bovine eye model chamber to evaluate the effects of iontophoresis on drug delivery and corneal properties. Transepithelial electrical resistance (TEER) was assessed as a predictor of corneal epithelial integrity in dissected bovine eyes. TEER measurements were correlated with methylene blue permeation, confirming a threshold of 4.2 kOhm·cm2 as an indicator of epithelial integrity. The model chamber enabled the application of drug solutions around a defined area of the cornea without leakage, facilitating the placement of electrodes and the application of constant electric currents. Applying iontophoresis at 2 mA/cm2 for 6 min significantly increased rhodamine B penetration into the cornea by nearly sixfold compared to passive diffusion (approximately 1.3 µg/cm2 vs. 0.24 µg/cm2), allowing detectable drug levels in the aqueous humor (27.9 ± 0.5 ng/mL). Morphological analyses revealed temporary changes in the cornea, including a 2.3-fold increase in surface roughness (from 44.6 nm to 105.3 nm) and mild collagen disorganization in the stroma, while Bowman's membrane remained intact. A significant increase in corneal stiffness was noted, with a 200 % rise in the area under the stress-strain curve after iontophoresis. These findings provide insights into iontophoresis-induced changes and highlight the model's potential for optimizing ocular drug delivery systems. Additionally, the model aligns with the 3Rs principles and could be instrumental in advancing the understanding of anterior segment diseases driven by structural and biomechanical alterations.

MicroRNAs in Corneal Diseases: Emerging Roles as Biomarkers, Regulators, and Therapeutics

MicroRNAs (miRNAs) are conserved, short, non-coding RNAs that play a crucial role in regulating gene expression. Emerging evidence suggests that miRNAs are closely involved in the pathophysiology of various corneal diseases, particularly in regulating corneal wound healing, inflammation and neovascularization. In this review, we summarized the recent progress of miRNAs in corneal diseases, especially focused on their application as diagnostic biomarkers, regulators of cell biology, and therapeutic targets. Recent advances in miRNA detection technology have made it possible to analyze minimal miRNAs in samples such as tears or exosomes, further enhancing the ability to identify disease-specific miRNA profiles and providing potential objective indicators for the early diagnosis of disease. Meanwhile, we summarized the mechanisms and pathways of multiple miRNAs in regulating various biological processes of corneal cells, as well as the advantages of studying miRNA compared to proteins or genes. Furthermore, we explore the potential of miRNAs-based therapies, especially introduce various miRNA delivery systems and challenges associated with clinical translation. This review highlights the need for further research to harness the full potential of miRNAs in treating various corneal diseases.

Stimulus-responsive nanomaterials for ocular antimicrobial therapy

Nanomaterials exhibit a promising new avenue for treating infectious keratitis, having garnered considerable interest in the ophthalmic medical community due to their unique properties including higher target specificity, enhanced bioactivity of loaded agents, reduced drug dosage, and stimulus-responsive drug release. These stimulus-responsive nanomaterial-mediated therapeutic strategies offer innovative approaches for managing ocular antimicrobial diseases. In this review, we aim to summarize current applications of stimulus-responsive nanotherapeutics for ocular antimicrobial therapy. We briefly introduce the basic ocular structure, ocular barrier, infectious keratitis classification, and its microenvironment. Following this, we summarize the nanotherapeutic antimicrobial strategies employed in treating ocular infections including endogenous stimulus-responsive ocular nanodrugs, sonodynamic therapy, and wearable device-based therapy, focusing on their design principles, developmental progress, and advantages and limitations. Finally, we critically evaluate the biosafety profiles of responsive nanomaterials, specifically addressing cytotoxicity and immune interactions. To conclude, we discuss key challenges in this research field and future opportunities with explicit emphasis on clinical translation and practical medical applications.

Supra-Hybrid Nanocarriers of Calix[4]Arene and PLGA for Enhanced Encapsulation and Extended Delivery of Gossypol in Cancer Therapy

In this study, supra-hybrid nanocarriers Cal-P NPs are developed by combining amphiphilic macrocyclic calix[4]arene and PLGA, offering adequate stability and multifunctionality as a single-platform nanocarrier resulting in monodispersed nanoparticles with unique synthetic tunability and an optimized hydrophobic core for therapeutic encapsulation. Unlike conventional multicomponent systems, the design eliminates the need for many external stabilizers while enabling tailored PEGylation for controlled drug release, as demonstrated with hydrophobic gossypol. This innovation addresses key limitations in cancer nanomedicine, including premature drug leakage and dose frequency, through a synthetically tunable and structurally optimized, bioresistant core. Gossypol, a model bioactive molecule with poor water solubility, is effectively loaded into the Cal-P NPs, significantly enhancing its aqueous solubility to millimolar concentrations. The encapsulation is driven by favorable interactions between gossypol and the hydrophobic groups of calixarene and PLGA, resulting in a stable core with sustained release properties. Validated through in vivo pharmacokinetic studies and detailed anticancer experiments in two distinct cancer cell lines, GP-Cal-P NPs demonstrated their potential as a robust platform for therapeutic delivery. These findings emphasize the versatility of Cal-P NPs in addressing challenges associated with hydrophobic drugs and highlight their promise for further preclinical and clinical development.

Development and in vitro and ex vivo characterization of a twin nanoparticulate system to enhance ocular absorption and prolong retention of dexamethasone in the eye: from lab to pilot scale optimization

Conventional eye drops show low bioavailability (below 20%) due to the eye's inherent tissue barriers and unique microenvironment. Recent advancements in pharmaceutical nanotechnology have explored various nanoparticle systems, such as micelles, liposomes, and nanoemulsions, to enhance corneal permeation and prolong drug retention. In this study, we propose a twin nanoparticulate system, combining the advantages of two nanoparticles to improve drug targeting and therapeutic efficacy. A dexamethasone-loaded liposome-microemulsion (LME) twin nanoparticulate system was developed using high-pressure homogenization and successfully scaled up. Both liposomes and microemulsions were of similar size (∼60 nm) and displayed uniform distribution (polydispersity index < 0.2) upon combination. The final formulation was hypo-osmolar (osmolality < 100 mOsm per Kg), making it ideal for dry eye relief. Drug release was extended for up to 8 h, following a non-Fickian diffusion pattern. The LME formulation, tested under different conditions (2-8 °C and 25 °C with 60% relative humidity), was found to be stable for 6 months. It showed no cytotoxicity in human corneal epithelial cells up to 10 μM drug concentration. Fluorescence microscopy revealed rapid nanoparticle uptake by cells within 5 minutes. Human corneal epithelial cells showed a marked reduction in inflammatory biomarkers (IL-6, IL-8, and TNF-α) after drug-loaded LME treatments, compared to the control. Corneal tissue imaging confirmed prolonged retention of nanoparticles within the tissue. A whole eye ex vivo permeation study demonstrated higher drug concentrations in the aqueous humour of LME drug-treated rabbit eyes compared to a reference product. This twin nanoparticulate system, loaded with dexamethasone, offers a promising next-generation treatment for dry eye disease (DED).

Indomethacin-incorporated microemulsion-laden contact lenses for improved ocular drug delivery and therapeutic efficacy

Conventional eye drops are associated with several limitations, including rapid drug clearance and low bioavailability, with only about 5% of the administered drug reaching the cornea to demonstrate therapeutic efficacy. Thus, to address these challenges, indomethacin (IND)-loaded microemulsion (Me)-embedded soft contact lenses (CLs) were developed to improve ocular drug delivery. The D-optimal mixture design was employed to optimize the composition of the Me formulation. Independent variables included Capmul MCM (oil phase), S mix (Tween 80/isopropyl alcohol), and water, while dependent variables were the globule size, transmittance (%), and drug release profile. The optimized Me exhibited a globule diameter of 45.69 ± 1.85 nm and a transmittance of 99.4% ± 1.59%. The globule dispersion index (PDI) was 0.33 ± 0.06, and the zeta potential (ZP) was 0.657 ± 0.012 mV. Soft CLs were developed using free radical polymerization and fortified with the Me loaded with the drug through direct loading and soaking techniques. Direct loading achieved a swelling percentage of 96.37% ± 1.8% and a transmittance of 96.5% ± 0.3%, while soaking resulted in 97.57% ± 1.4% swelling and 97.3% ± 1.3% transmittance. A drug content of 19.76 ± 0.23 μg per lenses for direct loading and 29.8 ± 0.2 μg per lenses for soaking demonstrated that the efficacy of the soaking technique was higher than that of direct loading. Moreover, drug release studies showed that the Me-laden lenses prepared using the direct loading technique released 44.00% ± 0.53% to 53.00% ± 0.59% of the drug within the first 6 h, while the lenses prepared via soaking released 62.58% ± 1.56% to 97.64% ± 1.52% of the drug within the first 6 h, followed by regulated drug release for up to 28 h, maintaining clarity and drug loading. Ocular irritancy test results indicated negligible irritation, suggesting that the Me-laden lenses are a safe and effective platform to manage ocular inflammation with the controlled delivery of IND.

PROTAC based targeted degradation of LRG1 for mitigating corneal neovascularization

Leucine-rich alpha-2-glycoprotein 1 (LRG1), a secretory glycoprotein associated with angiogenesis, inflammation, fibrosis, and other pivotal pathophysiological processes, is significantly upregulated in corneal neovascularization (CNV), where it drives neovascularization via the TGF-β-Smad signaling pathway, making it a potential therapeutic target for CNV. This study employs proteolysis-targeting chimera (PROTAC) technology, utilizing our newly developed PROTAC agent, ETTAC-2, to selectively degrade LRG1 in a mouse model of alkali burn-induced CNV. The cellular study revealed that ETTAC-2 effectively degraded LRG1 in a time- and dose-dependent manner, with a half-maximal degradation concentration (DC50) of 13.52 μM. In vivo findings confirmed that ETTAC-2 significantly reduced LRG1 levels in corneal neovascular tissues and inhibited the release of angiogenic factors by suppressing the TGF-β-Smad1/5/9 pathway, thus attenuating CNV progression. To enhance corneal drug delivery, ETTAC-2 was encapsulated in liposomes to form Lipo@ETTAC-2, which enhanced drug retention on the corneal surface, resulting in superior therapeutic outcomes in CNV models. This study underscores the pivotal role of LRG1 in CNV and positions Lipo@ETTAC-2 as a promising candidate for CNV therapy.

Transfersomes: a next-generation drug delivery system for topical ocular drug delivery

INTRODUCTION

The eye is a complex organ with several anatomical and physiological barriers that make ocular drug delivery an ongoing challenge. Transfersomes (TFS) are deformable vesicles that have been extensively applied to enhance transdermal drug delivery. However, their application in ocular drug delivery remains largely unexplored.

AREAS COVERED

This review highlights the challenges typically associated with ocular drug delivery and emphasizes the inherent properties of TFS that enable them to overcome these challenges. The influence of excipients and critical process parameters on TFS characteristics have been discussed in detail with an emphasis on the fabrication and characterization techniques typically employed for TFS development and optimization. Furthermore, recent studies evaluating the application of TFS in ocular drug delivery have been discussed in depth.

EXPERT OPINION

The unique stress-responsive and deformable nature of TFS makes them promising carriers for ocular drug delivery. However, further research in this direction is needed to understand their penetration mechanism and elucidate their potential for sustained and targeted drug delivery to ocular tissues. Moreover, further research is needed to optimize the stability and scalability of TFS to encourage their translation to the market.

Ocular drug delivery systems based on nanotechnology: a comprehensive review for the treatment of eye diseases

Ocular drug delivery is a significant challenge due to the intricate anatomy of the eye and the various physiological barriers. Conventional therapeutic approaches, while effective to some extent, often fall short in effectively targeting ocular diseases, resulting in suboptimal therapeutic outcomes due to factors such as poor ocular bioavailability, frequent dosing requirements, systemic side effects, and limited penetration through ocular barriers. This review elucidates the eye's intricate anatomy and physiology, prevalent ocular diseases, traditional therapeutic modalities, and the inherent pharmacokinetic and pharmacodynamic limitations associated with these modalities. Subsequently, it delves into nanotechnology-based solutions, presenting breakthroughs in nanoformulations such as nanocrystals, liposomes, dendrimers, and nanoemulsions that have demonstrated enhanced drug stability, controlled release, and deeper ocular penetration. Additionally, it explores a range of nanosized carriers, including nano-structured lipid carriers, hydrogels, nanogels, nanoenzymes, microparticles, conjugates, exosomes, nanosuspensions, viral vectors, and polymeric nanoparticles, and their applications. Unique insights include emerging innovations such as nanowafers and transcorneal iontophoresis, which indicate paradigm shifts in non-invasive ocular drug delivery. Furthermore, it sheds light on the advantages and limitations of these nanotechnology-based platforms in addressing the challenges of ocular drug delivery. Though nano-based drug delivery systems are drawing increasing attention due to their potential to enhance bioavailability and therapeutic efficacy, the review ends up emphasizing the imperative need for further research to drive innovation and improve patient outcomes in ophthalmology.

Evaluation of the effect of grape seed extract- loaded chitosan nanoparticles on cryptosporidiosis in dexamethasone immunosuppressed male mice

Cryptosporidiosis is a worldwide health problem that results in an economic loss. The disease is caused by the protozoan Cryptosporidium spp. Individuals with suppressed immunity, like those with organ transplantation, cancer and human immunodeficiency virus syndrome, suffer from the infection that may lead to the death. Nitazoxanide (NTZ) is the approved FDA treatment for cryptosporidiosis in immunocompetent individuals. There is an urgent need to find a new natural treatment that can replace NTZ in immunosuppressed hosts. The study aimed to use grape seed extract loaded chitosan nanoparticles (GSEx-CHNPs) in treatment of cryptosporidiosis in immunosuppressed male mice. GSEx was prepared by the alcoholic extraction method followed by the identification of its bioactive components. GSEx-CHNPs were synthesized by ionic gelation method and physically characterized then their activities were examined in vitro. The experimental groups, included immunocompetent and immunosuppressed groups, was treated with NPs for 14 days post infection (PI). The results showed the presence of many phenolic compounds in the GSEx. GSEx-CHNPs significantly improved the loss in animals body weight, cleared the infection and amolerated the serum cytokines levels. GSEx-CHNPs showed anti-cryptosporidial activity especially in immunosuppressed mice model. Where, it ameliorated the disturbance in the cytokine profile leading to an anti-inflammatory response.

Nano-based drug delivery systems for the treatment of non-infectious uveitis

Background

Uveitis is one of the most prevalent causes of global visual impairment. The current approaches to treating non-infectious uveitis (NIU) involve the utilization of corticosteroids, immunosuppressant and biologics agents. Nevertheless, the intricate ocular anatomy barriers and adverse side effects of the drugs pose significant obstacles to effective treatment outcomes.

Main text

To improve drug bioavailability and therapeutic outcomes for NIU while minimize side effects, researchers are committed to developing novel nano-based drug delivery systems (DDS), which have the capacity to achieve targeted delivery, increase bioavailability, achieve sustained release, reduce side effects and improve therapeutic effects. Thus, DDS based on nanotechnology, including liposome, dendrimer, hydrogels, nanoparticles, nanomicelles, nanosuspensions and nanoemulsions have emerged as promising alternatives to conventional ocular delivery methods for the management of NIU.

Conclusions

In this review, we summarize the current therapeutic challenges faced by NIU and describe various nano-based intraocular DDS involved in the treatment of NIU. It is concluded that nano-based DDS is an appealing approach to addressing the unmet needs for the treatment of NIU.

Application of Nanomaterials in the Diagnosis and Treatment of Retinal Diseases

In recent years, nanomaterials have demonstrated broad prospects in the diagnosis and treatment of retinal diseases due to their unique physicochemical properties, such as small-size effects, high biocompatibility, and functional surfaces. Retinal diseases are often accompanied by complex pathological microenvironments, where conventional diagnostic and therapeutic approaches face challenges such as low drug delivery efficiency, risks associated with invasive procedures, and difficulties in real-time monitoring. Nanomaterials hold promise in addressing these limitations of traditional therapies, thereby improving treatment precision and efficacy. The applications of nanomaterials in diagnostics are summarized, where they enable high-resolution retinal imaging by carrying fluorescent probes or contrast agents or act as biosensors to sensitively detect disease-related biomarkers, facilitating early diagnosis and dynamic monitoring. In therapeutics, functionalized nanocarriers can precisely deliver drugs, genes, or antioxidant molecules to retinal target cells, significantly enhancing therapeutic outcomes while reducing systemic toxicity. Additionally, nanofiber materials possess unique properties that make them particularly suitable for retinal regeneration in tissue engineering. By loading neurotrophic factors into nanofiber scaffolds, their regenerative effects can be amplified, promoting the repair of retinal neurons. Despite their immense potential, clinical translation of nanomaterials still requires addressing challenges such as long-term biosafety, scalable manufacturing processes, and optimization of targeting efficiency.

Natural deep eutectic solvents (NADES) in drug delivery systems: Characteristics, applications, and future perspectives

Deep eutectic solvents (DESs) are a class of low-melting mixtures formed by the hydrogen-bond interactions between hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs) in specific molar ratios. Their unique physicochemical properties enable DESs to significantly enhance drug solubility and permeability, while also serving as carriers to facilitate efficient drug delivery. A subclass of DESs, natural deep eutectic solvents (NADESs), is found in the metabolites of natural organisms, such as plants. With low toxicity and biodegradability, NADESs possess distinct advantages for applications in the pharmaceutical field.The therapeutic efficacy of drugs is often limited by imprecise release mechanisms, leading to the metabolism or degradation of a portion of the drug before it reaches the target site, thereby reducing its effectiveness. Moreover, many drugs exhibit poor solubility and stability, resulting in low efficiency during absorption and metabolism, which further diminishing their therapeutic impact. NADESs, with their excellent tunability and biocompatibility, have demonstrated great potential in drug delivery systems.This paper first provides an overview of the fundamental characteristics of NADESs, followed by a detailed summary of recent advancements and applications of NADESs across various administration routes, including transdermal, mucosal, and inhalation drug delivery. Finally, the paper explores the prospects of NADESs in novel drug delivery systems and proposes strategies for optimizing their performance to promote clinical applications.

Native/modified dextran-based nanogel in delivering drug and management of ocular complications: a review

Ocular nanogels have emerged as a promising therapeutic approach, and nanotechnology has speed up the growth of the pharmaceutical and medical technology sectors. The physiological and anatomical barriers of the eye limit the use of traditional ocular preparations, which leads to low drug bioavailability and a brief retention period. This presents a serious problem for patients, doctors, and chemists. Nevertheless, nanogels can encapsulate medications within three-dimensional crosslinked polymeric networks and provide controlled and prolonged drug delivery by using particular structural layouts and unique preparation techniques, improving therapeutic efficacy and patient compliance. Dextran and its variants, a naturally occurring polysaccharide, have drawn a lot of interest in developing delivery systems for use in pharmaceutical and medical applications. Many dextran-based delivery systems with customized geometries and features have been fabricated recently, such as hydrogels, nanogels, magnetic nanoparticles, nanoemulsions, self-assembled micelles and nanoparticles, and microparticles. The review presents advancement and therapeutic potential of dextran-based nanogels for the treatment of various eye conditions, such as cataract, conjunctivitis, glaucoma, dry eye syndrome, age-related macular degeneration, and corneal ulcers. Moreover, the process for development and assessing these nanomedicines, emphasizing their safety and effectiveness as established by preclinical, toxicological, clinical assessments, and patent updates, has been elaborated.

Enhancing glaucoma care with smart contact lenses: An overview of recent developments

Glaucoma is a leading cause of irreversible blindness worldwide, affecting millions of individuals due to its progressive damage to the optic nerve, often caused by elevated intraocular pressure (IOP). Conventional methods of IOP monitoring, such as tonometry, provide sporadic and often inaccurate readings due to fluctuations throughout the day, leaving significant gaps in diagnosis and treatment. This review explores the transformative potential of smart contact lenses equipped with continuous IOP monitoring and therapeutic capabilities. These lenses integrate advanced materials such as graphene, nanogels, and magnetic oxide nanosheets alongside sophisticated biosensing and wireless communication systems. By offering continuous, real-time data, these lenses can detect subtle IOP fluctuations and provide immediate feedback to patients and clinicians. Moreover, drug-eluting capabilities embedded in these lenses present a groundbreaking approach to glaucoma therapy by improving medication adherence and providing controlled drug release directly to the eye. Beyond IOP management, these innovations also pave the way for monitoring biochemical markers and other ocular diseases. Challenges such as biocompatibility, long-term wearability, and affordability remain, but the integration of cutting-edge technologies in smart contact lenses signifies a paradigm shift in glaucoma care. These developments hold immense promise for advancing personalized medicine, improving patient outcomes, and mitigating the global burden of blindness.

Stable dispersion and prolonged dissolution of hydrophilic pharmaceutical achieved by room-temperature atmospheric pressure atomic layer deposition

We demonstrate atomic layer deposition of SiO2 films on hydrophilic diclofenac sodium pharmaceutical powder under ambient conditions. We reveal that the SiO2 layer not only prolongs the dissolution but also enhances the surface zeta potential of the coated products, preventing sedimentation and enabling a highly stable dispersion in water.

Biocompatible Hyaluronic Acid-Stabilized Copper Nanoparticles for the Selective Oxidation of Morin Dye by H2O2

In this study, we report the synthesis and characterization of biocompatible hyaluronic acid-stabilized copper nanoparticles (HA-CuNPs) and their catalytic evaluation in the oxidation of morin as a model compound. HA-CuNPs have been characterized by several state-of-the-art analytical techniques, such as FESEM, STEM, UV-Vis, DLS, zeta potential, FTIR and XRD analyses. The average particle size and surface zeta potential of HA-CuNPs were determined to be 35 nm and -28 mV, respectively. The catalytic activity of HA-CuNPs was investigated in the oxidative degradation of morin dye in the presence of H2O2. The kinetic data show that the oxidation process follows a pseudo-first-order reaction, and the rate constant is dependent on the concentrations of morin, H2O2, and HA-CuNPs. In addition, HA-CuNPs were employed for the selective oxidation of morin on four important synthetic dyes, i.e., Congo red, methylene blue, zinc-phthalocyanine, and quinizarin. The high selectivity indicates the possible use of HA-CuNPs as low-temperature bleach catalysts for the oxidation of stains such as tea, coffee, and red wine, which contain polyphenolic compounds like morin. Further, cytotoxicity studies demonstrated the low toxicity and high biocompatibility of HA-CuNPs to Caco-2 human colorectal adenocarcinoma cells, MCF-7 human breast cancer cells, and HUVEC normal human umbilical vein endothelial cells. Combining biocompatibility with high catalytic activity could boost the potential of this eco-friendly nanocatalyst in various applications, such as wastewater treatment, laundry, textile, and wood pulp bleaching.

Quercetin loaded biogenic squalene nano-lipid carriers for the treatment of dry eye syndrome

In this study, quercetin-incorporated squalene nanostructured lipid carriers (QS-NLCs) were developed to mitigate the pathological conditions of dry eye disease (DED). The melt emulsification method was used to prepare QS-NLCs. The resulting NLCs have 93.74 ± 9.32 nm particle size, 43.8 ± 5.42 % drug loading and showed good stability for 90 days at different storage conditions. The structural characterization of NLCs was carried out through DSC, FTIR, and XRD, and the morphological study was conducted using TEM analysis. The morphological study emphasised no agglomeration was present in the formulation, and further -31.47 ± 2.18 mV zeta potential supported the TEM analysis. Also, the QS-NLCs showed a release pattern in which more than 70 % of the drug was released in the medium in 1 h. After that, a sustained release pattern was observed for 6 h. However, QS-NLCs also showed higher ex-vivo corneal permeation, i.e., ∼2.5-fold, as compared to free quercetin. Also, no significant difference was observed in the moisture retention capacity of NLCs when compared with control glycerin. Further, the QS-NLCs showed good anti-inflammatory and cytotoxicity activities against RAW 264.7 and HCECs cell lines, respectively. Furthermore, 18.22 ± 1.23 mm of Schirmer score in a 5-day tear production study and a 2.79-fold increased half-life (T1/2), 3.02-fold enhanced area under the curve (AUC0-∞), and 2.88-fold higher mean retention time (MRT0-∞) were obtained which signified the higher bioavailability of QS-NLCs with higher ocular tolerance ensured by modified Draize test. Most importantly, the proposed QS-NLCs improved the pharmacological activities of quercetin against DED.

Enhanced in vivo performance of topical ocular acetazolamide nanocrystals: A novel approach for glaucoma treatment

High intraocular pressure (IOP) is the main risk factor for glaucoma progression. Acetazolamide (AZM) presents a potent IOP-lowering effect but is only administered orally due to its low aqueous solubility and ocular permeability. This study aimed to develop AZM nanocrystals (AZM-NC) as an alternative for its topical ocular delivery. AZM-NC were obtained by wet bead milling technique followed by spray-drying, and a mixture design study was conducted to evaluate the optimal drug-to-stabilizer ratio regarding colloidal properties and stability. AZM-NC exhibited an average particle size of 299.7 ± 8.8 nm, a polydispersity index of 0.13 ± 0.01, and a zeta potential of -29.0 ± 0.9 mV, which remained mostly unchanged for at least 60 days when the dried powder was stored at room temperature. Fourier-transformed spectroscopy and powder X-ray diffraction analyses revealed no chemical or crystallinity changes in AZM-NC compared with AZM, respectively. Additionally, AZM-NC demonstrated increased drug saturation concentration, globular shapes, and higher adhesive properties than normal-sized AZM powder. Topical ocular administration of AZM-NC in albino male rabbits showed no clinical signs of ocular damage. Further, in vivo studies revealed a significant IOP reduction of up to 32 % of the basal IOP (-4.8 ± 1.2 mmHg, p < 0.05) in normotensive rabbit eyes (n = 7), after 4 h of AZM-NC suspension topical application, compared to groups treated with AZM suspension, normal saline solution and, AZOPT® (-1.8 ± 1.4 mmHg). Thus, AZM-NC could present a promising approach for developing an eye drop formulation for the localized management of glaucoma.

Optimization of methods for isolation and purification of outer membrane vesicles (OMVs) from Neisseria lactamica

Outer membrane vesicles (OMVs) are nanoparticles released by Gram-negative bacteria during growth, mainly under stress conditions. OMV-based vaccines have played an important role in vaccination against Neisseria meningitidis serogroup B (MenB), stimulating research into novel approaches for developing more effective vaccines. OMVs released by the bacterium Neisseria lactamica have emerged as a promising platform for new vaccine development, especially as carriers in subunit vaccines. Despite their importance, some challenges remain in obtaining and purifying OMVs. The most commonly employed methods for OMV isolation and purification are ultracentrifugation (UC) and size exclusion chromatography (SEC). However, these techniques could present limitations for large-scale production and often result in low yields. This study investigated techniques such as tangential flow filtration (TFF), membrane chromatography, and mixed-mode (multimodal) chromatography as potential replacements for UC and SEC. Among the TFF methods evaluated, the sample obtained on the membrane with a 300-kDa cutoff showed a profile more similar to UC but with more than double the total protein recovery. Sartobind® Q membrane chromatography was ineffective for OMV purification, in the conditions evaluated, with a recovery of 8.7%. Conversely, multimodal Capto™ Adhere chromatography recovered 59.0%, while Capto™ Core 400 yielded a recovery of 72.0%, proving to be more effective for purification when analyzed by high-performance liquid chromatography (HPLC). Thus, combining TFF with a 300-kDa membrane followed by Capto™ Core 400 chromatography can be applied as strategy for large-scale applications offering high recovery and purity. KEY POINTS: • Evaluation of TFF, membrane and multimodal chromatography techniques for OMV purification. • Improved Neisseria lactamica OMV yields combining TFF and multimodal chromatography. • A process for OMV purification from a non-pathogenic organism feasible to scale up.

Nanotechnology-based non-invasive strategies in ocular therapeutics: Approaches, limitations to clinical translation, and safety concerns

The eye is a highly sensitive and vital component that significantly affects human quality of life. Diseases that affect the eye are major contributors to visual impairment and blindness and can have a profound effect on an individual's well-being. Ocular drug delivery is challenging because of physiological and anatomical barriers. Invasive Intravitreal administration is primarily used for the treatment and management of posterior segmental disease. However, frequent intravitreal administration is associated with adverse effects. Furthermore, topical administration results in less than 5% ocular bioavailability, leading to a void in the safe and efficacious management of posterior segment diseases. Nanocarrier-based systems have been well explored as ocular therapeutics to overcome the sub-therapeutic management attributed to conventional eye drops and physiological and anatomical barriers. Since the first report of nanoparticles to date, the nanocarrier system has come a long way with the simplicity and versatility offered by the system. Significant progress has been made in the development of noninvasive nanocarrier systems and their interactions with the ocular surface. The nanocarrier system enhances precorneal retention, limits nontherapeutic absorption, and offers controlled drug release. This review aims to provide an overview of the recent advancements in noninvasive nanocarrier-based topical ocular drug delivery systems, including their interaction with the ocular surface, the barriers to their translation to clinical settings, and the associated scale-up challenges.

Microneedle Delivery of Heterologous Microparticulate COVID-19 Vaccine Induces Cross Strain Specific Antibody Levels in Mice

BACKGROUND

In recent years, the COVID-19 pandemic has significantly impacted global health, largely driven by the emergence of various genetic mutations within the SARS-CoV-2 virus. Although the pandemic phase has passed, the full extent of the virus's evolutionary trajectory remains uncertain, highlighting the need for continued research in vaccine development to establish a cross-reactive approach that can effectively address different variants. This proof-of-concept study aimed to assess the effectiveness of microparticulate vaccine delivery through the minimally invasive microneedle route of administration, using a heterologous prime-booster strategy against the SARS-CoV-2 virus.

METHOD

This strategy uses the whole inactivated virus of the Delta variant for the prime dose and the whole inactivated virus of the Omicron variant for the booster dose, with alum as an adjuvant. The formulation of microparticles involves encapsulating the antigens in poly lactic-co-glycolic acid (PLGA) polymer, which provides sustained release and enhances immunogenicity while protecting the antigen. Microparticles were tested for in vitro assays, and characterization included particle size, zeta potential, and encapsulation efficacy. Furthermore, serum was collected post-administration of the vaccine in mice and was tested for antibody levels.

RESULT

In vitro assays confirmed the non-cytotoxicity and the ability of microparticles to activate the immune response of the vaccine particles. Administering this microparticulate vaccine via microneedles has proven effective for delivering vaccines through the skin. We also observed significantly higher antigen-specific antibody levels and cross-reactivity in the strains.

CONCLUSIONS

Our adjuvanted microparticulate-based heterologous prime-booster vaccine strategy showed cross-reactivity among the strains and was successfully delivered using microneedles.

Biogenic Amino Acid Cross-Linked Hyaluronic Acid Nanoparticles Containing Dexamethasone for the Treatment of Dry Eye Syndrome

Ocular barriers, poor retention time, and frequent ocular discharge suppress the activity of Dexamethasone. Arginine (Arg) and hyaluronic acid (HA) are crucial for maintaining ocular health because of their unique biological benefits. In this study, we investigated the cationic properties of arginine to develop dexamethasone-loaded HA nanoparticles (ADHA NPs) and evaluated their therapeutic potential in alleviating dry eye syndrome using various reported in-vitro and in-vivo techniques. The ionic cross-linking method was used to prepare ADHA NPs. The ADHA NPs exhibited nearly 94.99 ± 4.16% drug release at the end of 6 h and followed the Korsemeyar-Peppas kinetic model (R2 = 0.9811). Moreover, the developed formulation exhibited a higher water retention capacity, i.e., 86.89 ± 1.41%, and revealed enhanced mucoadhesion characteristics. ADHA NPs also exhibited significant anti-inflammatory effects (p < 0.001) compared to dexamethasone in LPS-induced RAW 264.7 cell lines against proinflammatory cytokines IL-1 β, NO and TNF-α. Furthermore, cell line studies in HCECs (human corneal epithelial cells) showed cytocompatibility and a dose-dependent uptake of ADHA NPs. ADHA NPs also maintained the cell integrity against 0.005% benzalkonium chloride (BAC) induced dry eye model on HCECs. Further, the Schirmer tear test showed twofold enhanced tear production in the developed formulation, and ADHA NPs seem to maintain the uniform structure of the tear. In vivo, drug retention studies ensured the good retention properties of ADHA NPs up to 12 h. In conclusion, ADHA NPs, because of their anti-inflammatory, mucoadhesiveness, modified drug release capacity, and higher drug retention properties, could serve as a potential therapeutic alternative for treating dry eye conditions.

Bringing ophthalmology into the scientific world: Novel nanoparticle-based strategies for ocular drug delivery

The distinctive benefits and drawbacks of various drug delivery strategies to supply corneal tissue improvement for sense organs have been the attention of studies worldwide in recent decades. Static and dynamic barriers of ocular tissue prevent foreign chemicals from entering and inhibit the active absorption of therapeutic medicines. The distribution of different medications to ocular tissue is one of the most appealing and demanding tasks for investigators in pharmacology, biomaterials, and ophthalmology, and it is critical for cornea wound healing due to the controlled release rate and increased drug bioavailability. It should be mentioned that the transport of various types of medications into the different sections of the eye, particularly the cornea, is exceedingly challenging because of its distinctive structure and various barriers throughout the eye. Nanoparticles are being studied to improve medicine delivery strategies for ocular disease. Repetitive corneal drug delivery using biodegradable nanocarriers allows a medicine to remain in different parts of the cornea for extended periods of time and thus improve administration route effectiveness. In this review, we discussed eye anatomy, ocular delivery barriers, as well as the emphasis on the biodegradable nanomaterials ranging from organic nanostructures, such as nanomicelles, polymers, liposomes, niosomes, nanowafers, nanoemulsions, nanosuspensions, nanocrystals, cubosomes, olaminosomes, hybridized NPs, dendrimers, bilosomes, solid lipid NPs, nanostructured lipid carriers, and nanofiber to organic nanomaterials like silver, gold, and mesoporous silica nanoparticles. In addition, we describe the nanotechnology-based ophthalmic medications that are presently on the market or in clinical studies. Finally, drawing on current trends and therapeutic approaches, we discuss the challenges that innovative optical drug delivery systems confront and propose future research routes. We hope that this review will serve as a source of motivation and inspiration for developing innovative ophthalmic formulations.

Localization of fluorescent gold nanoparticles throughout the eye after topical administration

The human eye is a highly intricate sensory organ. When a condition requiring treatment occurs, eyedrops, which represent 90% of all ophthalmic treatments, are most frequently used. However, eyedrops are associated with low bioavailability, with less than 0.02% of therapeutic molecules reaching the anterior chamber. Thus, new delivery systems are required to ensure sufficient drug concentration over time at the target site. Gold nanoparticles are a promising avenue for drug delivery; however, they can be difficult to track in biological systems. Fluorescent gold nanoparticles, which have the same ultrastability and biocompatibility as their nonfluorescent counterpart, could act as an effective imaging tool to study their localization throughout the eye after administration. Thus, this study (1) synthesized and characterized fluorescent gold nanoparticles, (2) validated similar properties between nonfluorescent and fluorescent gold nanoparticles, and (3) determined their localization in the eye after topical application on ex vivo rabbit eyes. The fluorescent gold nanoparticles were synthesized, characterized, and identified in the cornea, iris, lens, and posterior segment of rabbit eyeballs, demonstrating tremendous potential for future drug delivery research.

Implications of nanotechnology for the treatment of Dry Eye Disease: Recent advances

Managing Dry Eye Disease (DED), a prevalent condition affecting the ocular surface, remains challenging despite advancements in diagnostics and therapies. Current treatments primarily involve lubricating eye drops and anti-inflammatory medications, which often require prolonged use and generally provide only symptomatic relief. The current study focuses on improving DED treatments through nano-drug delivery technologies and advanced formulations. These systems aim to address the limitations of conventional therapies by providing extended, targeted, and sustained drug release. The development of innovative nanomaterials offers improved precision, control, and customization for DED management. By enabling controlled and sustained drug release, these nano-drug delivery systems could offer longer-lasting relief, addressing the chronic nature of DED more effectively than current symptomatic therapies. Future research should focus on integrating multiple therapeutic agents within these systems to simultaneously target inflammation and tear film instability. This review examines the potential of nano-based materials for DED treatment, with a particular emphasis on lipid-based, polymer-based and polysaccharide-based systems.

Lipid nanoparticle-mediated intracameral mRNA delivery facilitates gene expression and editing in the anterior chamber of the eye

Lipid nanoparticles (LNPs) have shown great potential in the field of gene therapy for retinal diseases. To expand on this application, we investigated LNP-mediated mRNA delivery to the anterior chamber of the eye via the intracameral (IC) route of administration. Here, we show that IC injections of LNPs facilitated protein expression and gene editing in the trabecular meshwork (TM). Administration of Cre-mRNA LNPs to Ai9 mice resulted in robust tdTomato expression in the angle and corneal endothelium. In C57BL/6 mice, mCherry-mRNA LNPs demonstrated localized protein expression in the TM, which peaked at 72 h and subsequently declined over 120 h. Additionally, LNPs encapsulating Cas9 mRNA with sgAi9 enabled in vivo gene editing in Ai9 mice, with up to 14.3 % editing efficiency. This induced tdTomato expression in the iridocorneal angle, validating the potential of LNPs for gene editing applications. Importantly, no ocular toxicity was observed, indicating the safety of the IC LNP administration. Our findings highlight the use of LNPs for targeted gene therapy and editing, paving the path for the treatment of diseases such as glaucoma in the anterior eye.

Excipients for Cerium Dioxide Nanoparticle Stabilization in the Perspective of Biomedical Applications

Rare earth metal nanoparticles, some of which are already widely used in medicine, are of growing interest in the modern scientific community. One of the promising rare earth metals for biomedical applications is cerium, specifically its oxide form, which is characterized by a higher level of stability and safety. According to a number of studies, cerium dioxide has a wide range of biological effects (regenerative, antimicrobial, antioxidant, antitumor), which justifies the interest of its potential application in medicine. However, these effects and their intensity vary significantly across a number of studies. Since cerium dioxide was used in these studies, it can be assumed that not only is the chemical formula important, but also the physicochemical parameters of the nanoparticles obtained, and consequently the methods of their synthesis and modification with the use of excipients. In this review, we considered the possibilities of using a number of excipients (polyacrylate, polyvinylpyrrolidone, dextran, hyaluronic acid, chitosan, polycarboxylic acids, lecithin, phosphatidylcholine) in the context of preserving the biological effects of cerium dioxide and its physicochemical properties, as well as the degree of study of these combinations from the point of view of the prospect of creating drugs based on it for biomedical applications.

One-Pot Synthesis of Amphiphilic Linear and Hyperbranched Polyelectrolytes and Their Stimuli-Responsive Self-Assembly in Aqueous Solutions

Stimuli-responsive polymeric nanostructures are compelling vectors for a wide range of application opportunities. The objective we sought was to broaden the array of self-assembling amphiphilic copolymers with stimuli-responsive characteristics by introducing a hydrophilic tunable monomer, (2-dimethylamino)ethyl methacrylate (DMAEMA), together with a hydrophilic one, lauryl methacrylate (LMA), within linear and branched copolymer topologies. Size exclusion chromatography was used to evaluate the resultant linear and hyperbranched copolymers' molecular weight and dispersity, and FT-IR and 1H-NMR spectroscopy techniques were used to delineate their chemical structure. The structural changes in the obtained self-organized supramolecular structures were thoroughly investigated using aqueous media with varying pH and salinity by dynamic light scattering (DLS), fluorescence spectroscopy (FS), and transmission electron microscopy (TEM). The nanoscale assemblies formed by the amphiphiles indicate significant potential for applications within the field of nanotechnology.

In Vitro Evaluation of the Safety and Antineoplastic Effects in Gastrointestinal Tumors of Nanostructured Lipid Carriers Loaded with Berberine

Background/Objectives: Natural substances have been a widely studied source of both pharmaceutical excipients and drugs. Berberine (BRB) is a benzylisoquinoline alkaloid isolated from different plant sources. It possesses various pharmacological properties including antibacterial, antitumor, antidiabetic, neuroprotective, hepatoprotective, anti-inflammatory, antioxidant, etc. However, the limited aqueous solubility hinders its application. Nanosized drug delivery systems are an innovative approach for addressing various challenges regarding drug delivery via different routes of administration. Their utilization could improve the solubility of active constituents. Methods: A melt-emulsification and ultrasonication technique was applied for the preparation of nanostructured lipid carriers (NLCs). They were thoroughly physicochemically characterized by the means of Dynamic Light Scattering, TEM, FTIR, DSC, TGA, and In Vitro release. The In Vitro efficacy and safety were evaluated on cholangiocarcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, lymphoma, fibroblast, and cardioblast cells, as well as rat liver microsomes by means of cytotoxicity assays and the comet assay. Results: The obtained nanoparticles had a spherical shape and size around 158.2 ± 1.8 nm with negative zeta potential. They revealed successful drug loading and improved dissolution of berberine in physiological conditions. The In Vitro safety studies showed that loading BRB in NLCs resulted in improved or retained cytotoxicity to tumor cell lines and reduced cytotoxicity to normal cell lines and liver microsomes. The NLC itself increased microsomal malondialdehyde (MDA) and comet formation. Conclusions: A successful preparation of NLCs with berberine is presented. The nanocarriers show favorable physicochemical and biopharmaceutical properties. The cellular experiments show that the NLC loading of berberine could improve its anticancer efficacy and safety. These findings highlight the potential applicability of berberine in gastrointestinal neoplasms and build the foundation for future practical translation.

Antibacterial Lecithin/Chitosan Nanoparticles for the Sustained Release of Ciprofloxacin to Treat Ocular Bacterial Infections

Ocular drug-delivery is one of the most challenging areas owing to nature of ocular tissues. Various nanoformulations have been designed and investigated for drug-delivery to achieve high drug bioavailability. The major focus of these preparations available in market is to utilize nanomaterial as drug-carrier only, with less focus on developing functional-nanomaterials, which is a key knowledge gap in the field. To address this, we developed a nanoparticulate system from bioactive-polymers, having intrinsic antimicrobial and mucoadhesiveness, loaded with ciprofloxacin (cipro) to treat ocular bacterial infections. Cipro-loaded lecithin/chitosan nanoparticles were prepared and characterized for their physiochemical properties. They exhibited good drug loading efficiency and showed sustained drug-release for 72 h, with slow release for first 4 h followed by a burst release in phosphate buffered saline and simulated tear fluid. Cipro-loaded nanoparticles were assessed for their antibacterial potential against Staphylococcus aureus (96 %) and Pseudomonas aeruginosa (72 %) using optical density, disc-diffusion method, live-dead assay, and demonstrated promising antibacterial properties. The drug-loaded nanoparticles showed good cytocompatibility (~90 %) towards murine fibroblasts and rabbit corneal cells. Being amphiphilic in nature, the nanoparticles exhibited mucoadhesiveness, hemocompatibility (<4 %) and, thus, proving to be a promising candidate for treating ocular infections. This approach ensures efficient drug delivery and synergic/additive therapeutic effects.

Nanotechnology in Ocular Drug Delivery: The Potential of Polymeric Micelles as a Drug Delivery Vehicle

Conventional ocular drug delivery systems face challenges like rapid clearance, high dosages, low compliance, and poor bioavailability. A novel solution utilizes mucoadhesive polymers for controlled release, enhancing drug effectiveness while reducing dosages and frequency. Polymeric micelles, nanosized colloidal DDS, are set to modify drug delivery for challenging drugs mainly belonging to Biopharmaceutical Classification System class II (low solubility and high permeability), class III (high solubility and low permeability), and class IV (low solubility and low permeability). Micelles solubilize poorly soluble drugs, shielding them from degradation and macrophage uptake and extending drug action. Their small size enables them to breach ocular barriers, elevating therapeutic impact and bioavailability. This review explores polymeric micelles' potential in ocular drug delivery, covering their introduction, formulation, preparation, characterization, applications, recent progress, and challenges through critical analysis of all possible research communications so far. The review also scrutinizes the transition from lab to clinical use. Polymeric micelles revolutionize ocular drug delivery by surmounting limitations through enhanced solubilization, protection, and sustained release. This comprehensive review highlights their potential to improve ocular drug delivery practices.

Optimized PLGA encapsulated SA-2 nanosuspension exhibits sustained intraocular pressure reduction in the mouse microbead occlusion model of ocular hypertension

Elevated intraocular pressure (IOP) is implicated in the structural and functional damage to the retinal ganglion cells (RGCs) in primary open-angle glaucoma (POAG). Topical IOP lowering agents provide short-term relief, necessitating frequent dosing. Moreover, non-adherence to frequent eyedrops administration contributes significantly to visual field loss and worsens the disease outcome. We optimized the poly (lactic-co-glycolic acid) (PLGA) nanoparticles encapsulation of hybrid antioxidant-nitric oxide donor SA-2 (SA-2NP), investigated its bioavailability, duration of IOP lowering efficacy, and effects on retinal function in the microbead model of ocular hypertension (OHT). SA-2 was bioavailable in the anterior and posterior segments after 1, 8, and 24 h post-single topical eyedrop administration. SA-2NP significantly lowered IOP (∼25-34%) and preserved the RGC function after weekly eyedrop administration for 3 weeks in C57BL/6J mice. In conclusion, the optimized SA-2NP formulation demonstrated optimal bioavailability, ocular safety, and prolonged IOP-lowering efficacy in the mouse microbead occlusion model of OHT.

Chemical and biological investigations on modified gemcitabine by nanoliposome structured on cholesterol, pectin, and phosphatidylcholine as an anticancer drug via a drug delivery system

Gemcitabine hydrochloride (GEM) mimics one of the building blocks of DNA and RNA, so it indicates possible chemotherapeutic effects. It prevents cancer cells from producing DNA and proteins, which ultimately leads to their death. The goal of this work is to modify the GEM medication by nanoforming nanoliposomes based on the composition of Cholesterol, pectin nanoparticles, and phosphatidylcholine (PhC). The drug in nanoliposome form is made using the precipitation method, and several approaches are employed to characterize it. UV-Vis spectroscopy is used to measure the release process of GEM from the lipids and its integration with them. Results of the combination efficiency for PhC.Pectin@GEM, PhC.GEM@Pectin, and PhC@Cholestrol.GEM were recorded at 78.8 %, 83 %, and 80 %, respectively. A UV-Vis spectrophotometer was used to determine the release efficiency of the nanoliposomes, which was measured at pH values of 3, 6.8, and 7.4. The in-vitro investigation employed SRB (Routine analysis IC50) to determine the modified drug's toxicity on breast adenocarcinoma (MCF-7) cells, while the in-vitro study assessed the produced nanoliposomes' capacity to do so. The conclusion is that to ascertain whether GEM medicine's nanoliposomes can effectively treat breast cancer in place of GEM medication, clinical trials are necessary to prove the ability for treatment.

Influence of Different Cationic Polymer-Based Micelles on the Corneal Behavior and Anti-Cataract Effect of Diosmetin

Background Despite many studies on polymer-incorporated nanocarriers for ophthalmic drug delivery, few have thoroughly explored the relationship between coating composition and performance. This study aimed to evaluate the effects of three commonly used cationic polymers-distearoyl phosphatidylethanolamine-polyethylene glycol 1000-poly(amidoamine) (DSPE-PEG1000-PAMAM), trimethyl chitosan (TMC), and (2,3-dioleoyloxypropyl) trimethylammonium chloride (DOTAP)-on the corneal behaviors and anti-cataract efficacy of diosmetin (DIO)-loaded micelles (D-M-P, D-M-T, and D-M-D, respectively). Methods The DIO-loaded micelles were prepared using the thin-film dispersion method and incorporated with the three polymers through hydrophobic interactions and electrostatic adsorption. Structural characterization was demonstrated by TEM imaging and particle size analyzer. In vitro release behavior was detected by the dialysis method. Cell viability of D-M-P, D-M-T, and D-M-D on L929 cells was detected by CCK-8 assays, with cellular uptake performed using coumarin 6 as the fluorescence indicator. Precorneal retention behaviors of these three vesicles were observed by In Vivo Imaging System. Transcorneal permeability was determined by modified Franz diffusion method and the permeation routes of the vesicles are investigated. Selenite-induced cataract model was established. The anti-cataract effects of three different DIO-loaded micelles were evaluated by the observation of lens opacity and antioxidant enzyme activities. Eye Irritation of the DIO in different preparations was estimated using the Draize test, along with H&E staining of the corneas. Results Structural characterization of DIO-loaded micelles revealed that the vesicles were spherical, with a uniform size distribution of around 28 nm, a similar surface potential of approximately 6.0 mV, and a high DIO entrapment efficiency of about 95%. Compared to the DIO suspension, all three formulations exhibited a significant sustained-release effect. They showed no signs of irritation and demonstrated increased IC50 values in L929 cells, indicating improved biocompatibility. Cellular uptake in human lens epithelial cells (HLECs) was assessed using confocal laser scanning microscopy. C-M-T displayed the highest fluorescence signals, with a cellular internalization 3.2 times greater than that of the solution group. Both C-M-T and C-M-P enhanced vesicle retention on the corneal surface by at least 47.8% compared to the Cou-6 solution. Furthermore, TMC facilitated the paracellular transport of vesicles into the deepest layers of the cornea and delivered DIO across the cornea, with a Papp value 3.11 times and 1.49 times those of D-M-D and D-M-P, respectively. In terms of therapeutic efficacy, D-M-T demonstrated the most significant attenuation of lens opacity, along with enhanced antioxidant enzyme activities and inhibition of lipid peroxidation. Conclusion The modification of micelle vesicles with different cationic polymers significantly influences their performance in ocular drug delivery. Among the tested formulations, D-M-T stands out due to its multiple advantages, including enhanced transcorneal drug delivery, therapeutic efficacy for DIO, and safety, making it the most promising candidate for ophthalmic applications.

Thiolated gellan gum/polyethylene glycol diacrylate hydrogels containing timolol maleate-loaded chitosan nanoparticles for ophthalmic delivery

The combination of hydrogels with nanoformulations can significantly enhance the delivery and effectiveness of drugs in ophthalmic drug delivery systems. In the current study, the polyethylene glycol diacrylate (PEGDA)/thiolated gellan gum (GGSH) hydrogels based on GGSH and PEGDA were prepared via thiol-ene reaction using Irgacure 2959 as a photoinitiator. To this end, the modification of GG was achieved by esterification of the hydroxyl groups of GG with the carboxyl group of mercaptopropionic acid with a free thiol amount of 95.5 μmol g-1. To provide sustained release, chitosan nanoparticles (CSNPs) containing timolol maleate (TM) with 56.4% entrapment efficiency were synthesized by the desolvation method and encapsulated in the developed hydrogel. The values of zeta potential and particle size of CSNPs were +26.0 mV and 182.4 nm, respectively. The physico/chemical properties of the hydrogels were investigated via texture analyzer, FT-IR, XRD, and SEM. Thein vitrodegradation, swelling behavior, rheological assessments, cell viability testing, and porosity determination were evaluated. With the increase in PEGDA concentration, the mechanical properties were increased. While the rate of swelling, degradation, and drug release were decreased. Thein vitrobiocompatibility of hydrogels was confirmed using the MTT test. According to anex vivostudy, ocular drug delivery using the obtained transparent hydrogels is promising due to improved drug permeation and sustained release of TM via CSNPs.

A mechanistic overview on green assisted formulation of nanocomposites and their multifunctional role in biomedical applications

The importance of nanocomposites constantly attains attention because of their unique properties all across the fields especially in medical perspectives. The study of green-synthesized nanocomposites has grown to be extremely fascinating in the field of research. Nanocomposites are more promising than mono-metallic nanoparticles because they exhibit synergistic effects. This review encapsulates the current development in the formulation of plant-mediated nanocomposites by using several plant species and the impact of secondary metabolites on their biocompatible functioning. Phyto-synthesis produces diverse nanomaterials with biocompatibility, environment-friendliness, and in vivo actions, characterized by varying sizes, shapes, and biochemical nature. This process is advantageous to conventional physical and chemical procedures. New studies have been conducted to determine the biomedical efficacy of nanocomposites against various diseases. Unfortunately, there has been inadequate investigation into green-assisted nanocomposites. Incorporating phytosynthesized nanocomposites in therapeutic interventions not only enhances healing processes but also augments the host's immune defenses against infections. This review highlights the phytosynthesis of nanocomposites and their various biomedical applications, including antibacterial, antidiabetic, antiviral, antioxidant, antifungal, anti-cancer, and other applications, as well as their toxicity. This review also explores the mechanistic action of nanocomposites to achieve their designated tasks. Biogenic nanocomposites for multimodal imaging have the potential to exchange the conventional methods and materials in biomedical research. Well-designed nanocomposites have the potential to be utilized in various biomedical fields as innovative theranostic agents with the subsequent objective of efficiently diagnosing and treating a variety of human disorders.

Inactivation of antibiotic resistant bacteria by nitrogen-doped carbon quantum dots through spontaneous generation of intracellular and extracellular reactive oxygen species

The widespread antibiotic resistance has called for alternative antimicrobial agents. Carbon nanomaterials, especially carbon quantum dots (CQDs), may be promising alternatives due to their desirable physicochemical properties and potential antimicrobial activity, but their antimicrobial mechanism remains to be investigated. In this study, nitrogen-doped carbon quantum dots (N-CQDs) were synthesized to inactivate antibiotic-resistant bacteria and treat bacterial keratitis. N-CQDs synthesized via a facile hydrothermal approach displayed a uniform particle size of less than 10 nm, featuring a graphitic carbon structure and functional groups including -OH and -NH2. The N-CQDs demonstrated antimicrobial activity against Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus, which was both dose- and time-dependent, reducing the survival rate to below 1 %. The antimicrobial activity was confirmed by live/dead staining. In in vivo studies, the N-CQDs were more efficient in treating drug-resistant bacterial keratitis and reducing corneal damage compared to the common antibiotic levofloxacin. The N-CQDs were shown to generate intracellular and extracellular ROS, which potentially caused oxidative stress, membrane disruption, and cell death. This antimicrobial mechanism was supported by scanning and transmission electron microscopy, significant regulation of genes related to oxidative stress, and increased protein and lactate dehydrogenase leakage. This study has provided insight into the development, application, and mechanism of N-CQDs in antimicrobial applications.

Drug delivery strategies to improve the treatment of corneal disorders

Anterior eye disorders including dry eye syndrome, keratitis, chemical burns, and trauma have varying prevalence rates in the world. Classical dosage forms based-topical ophthalmic drugs are popular treatments for managing corneal diseases. However, current dosage forms of ocular drugs can be associated with major challenges such as the short retention time in the presence of ocular barriers. Developing alternative therapeutic methods is required to overcome drug bioavailability from ocular barriers. Nanocarriers are major platforms and promising candidates for the administration of ophthalmic drugs in an adjustable manner. This paper briefly introduces the advantages, disadvantages, and characteristics of delivery systems for the treatment of corneal diseases. Additionally, advanced technologies such as 3D printing are being considered to fabricate ocular drug carriers and determine drug dosages for personalized treatment. This comprehensive review is gathered through multiple databases such as Google Scholar, PubMed, and Web of Science. It explores information around "ocular drug delivery systems'', "nano-based drug delivery systems'', "engineered nanocarriers'', and "advanced technologies to fabricate personalized drug delivery systems''.

Size Distribution of Zinc Oxide Nanoparticles Depending on the Temperature of Electrochemical Synthesis

One of the methods for obtaining zinc oxide nanoparticles (ZnO NPs) is electrochemical synthesis. In this study, the anodic dissolution process of metallic zinc in alcohol solutions of LiCl was used to synthesize ZnO NPs. The products were obtained as colloidal suspensions in an electrolyte solution. Due to the small size and ionic nature of the zinc oxide molecule, colloidal nanoparticles tend to cluster into larger groupings, so the size of nanoparticles in solutions will differ from the size of nanoparticles observed in ZnO powders after solvent evaporation. The main goal of this research is to investigate the influence of the temperature of synthesis and the kind of alcohol on the size of ZnO NP micelles. Nanocrystals of zinc oxide were obtained in all tested alcohols: methanol, ethanol, and 1-propanol. The particle size was determined using the Dynamic Light Scattering (DLS) method. It was observed that the particles synthesized in methanol were the largest, followed by smaller particles in ethanol, while the smallest particles were obtained in 1-propanol. Additionally, the particles obtained in ethanol were the most uniform in size, showing the highest level of size homogeneity.

Nanosuspension Innovations: Expanding Horizons in Drug Delivery Techniques

Nanosuspensions (NS), with their submicron particle sizes and unique physicochemical properties, provide a versatile solution for enhancing the administration of medications that are not highly soluble in water or lipids. This review highlights recent advancements, future prospects, and challenges in NS-based drug delivery, particularly for oral, ocular, transdermal, pulmonary, and parenteral routes. The conversion of oral NS into powders, pellets, granules, tablets, and capsules, and their incorporation into film dosage forms to address stability concerns is thoroughly reviewed. This article summarizes key stabilizers, polymers, surfactants, and excipients used in NS formulations, along with ongoing clinical trials and recent patents. Furthermore, a comprehensive analysis of various methods for NS preparation is provided. This article also explores various in vitro and in vivo characterization techniques, as well as scale-down technologies and bottom-up methods for NS preparation. Selected examples of commercial NS drug products are discussed. Rapid advances in the field of NS could resolve issues related to permeability-limited absorption and hepatic first-pass metabolism, offering promise for medications based on proteins and peptides. The evolution of novel stabilizers is essential to overcome the current limitations in NS formulations, enhancing their stability, bioavailability, targeting ability, and safety profile, which ultimately accelerates their clinical application and commercialization.

Nanotherapy for Neural Retinal Regeneration

Retinal diseases can severely impair vision and even lead to blindness, posing significant threats to both physical and mental health. Physical retinal regenerative therapies are poised to revolutionize the treatment of various disorders associated with blindness. However, these therapies must overcome the challenges posed by the protective inner and outer blood‒retinal barriers. Nanotechnology applications in ophthalmology have shown great potential in addressing the issue of drug delivery to the eye. Moreover, nanotechnology-based therapeutics can have profound clinical impacts on retinopathy, particularly retinal regeneration, thereby improving patient outcomes. Continuous advancements in nanotechnology are being applied to regenerate lost or damaged eye tissues and to treat vision loss and blindness caused by various retinal degenerative diseases. These approaches can be categorized into three main strategies: i) nanoparticles for delivering drugs, genes, and other essential substances; ii) nanoscaffolds for providing biocompatible support; and iii) nanocomposites for enhancing the functionality of primary or stem cells. The aim of this comprehensive review is to present the current understanding of nanotechnology-based therapeutics for retinal regeneration, with a focus on the perspective functions of nanomaterials.

Effective tailoring of cefepime into bilosomes: A promising nanoplatform for enhancing oral absorption, extending half-life, and evaluating biocompatibility, antibacterial, anti-biofilm, anti-breast cancer activity, ex-vivo, and in-vivo studies

The clinical implication of cefepime HCl (CEF) is compromised owing to restricted oral bioavailability and harmful adverse effects without any authorized oral formulation available. The present investigation provides an innovative sustained-release oral drug delivery strategy that tackles the challenges of limited oral bioavailability and prolongs the half-life of CEF. Accordingly, CEF was loaded into a bilosome, a liposome or noisome-based vesicle employing bile salt as a permeation enhancer. Despite its hydrophilic nature, the drug was effectively loaded into bilosomes. Nine various formulas were fabricated by a reverse phase evaporation method. The resulting vesicles increased the encapsulation efficiency (EE %) from 39.31 ± 0.03 % to 63.09 ± 0.01 %, drug loading capacity (DLC %) from 6.99 ± 0.25 to 42.91 ± 0.11 %, the particle size (PS) from 264 ± 13.52 nm to 405.40 ± 8.91 nm, and the polydispersity index (PDI) values ranged from 0.243 ± 0.040 to 0.430 ± 0.050. The zeta potential (ZP) changed from - 35.67 ± 3.73 mV to - 62.21 ± 2.21 mV. Further, the release profile exhibited dual release pattern within 24 h, with the percentage of release (CR %) expanding from 42 ± 0.13 % to 69.16 ± 0.09 %. The selected formula was found to be B3 with EE % = 56.61 ± 0.02 %, PS = 264 ± 13.52 nm, ZP = - 62.21 ± 2.21 mV, PDI = 0.430 ± 0.050, CR % = 52.94 ± 0.06 %, and IC50 of 3.4 ± 0.40 µg/ml against MCF-7 cells with scattered spherical non-agglomerated vesicles. Additionally, it exhibited higher anti-MRSA biofilm, relative bioavailability (5.1 fold), and antimicrobial capacity against P. aeruginosa, E. coli, B. subtilis, and S. aureus compared to pure CEF. Our data demonstrate that bilosome is a powerful nanocarrier for oral delivery of cefepime, boosting its biological impacts and pharmacokinetic profile.

Nanoparticles as Drug Delivery Carrier-synthesis, Functionalization and Application

In recent years, advancements in chemistry have allowed the tailoring of materials at the nanoscopic level as needed. There are mainly four main types of nanomaterials used as drug carriers:metal-based nanomaterials, organic nanomaterials, inorganic nanomaterials, and polymer nanomaterials. The nanomaterials as a drug carrier showed advantages for decreased side effects with a higher therapeutic index. The stability of the drug compounds are increased by encapsulation of the drug within the nano-drug carriers, leading to decreased systemic toxicity. Nano-drug carriers are also used for controlled drug release by tailoring system-made solubility characteristics of nanoparticles by surface coating with surfactants. The review focuses on the different types of nanoparticles used as drug carriers, the nanoparticle synthesis process, techniques of nanoparticle surface coating for drug carrier purposes, applications of nano-drug carriers, and prospects of nanomaterials as drug carriers for biomedical applications.

Applications and latest research progress of liposomes in the treatment of ocular diseases

The special structure of eyes and the existence of various physiological barriers make ocular drug delivery one of the most difficult problems in the pharmaceutical field. Considering the problems of patient compliance, local administration remains the preferred method of drug administration in the anterior part of eyes. However, local administration suffers from poor bioavailability, need for frequent administration, and systemic toxicity. Administration in the posterior part of the eye is more difficult, and intravitreal injection is often used. But intravitreal injection faces the problems of poor patient compliance and likely side effects after multiple injections. The development of nanocarrier technology provides an effective way to solve these problems. Among them, liposomes, as the most widely used carrier in clinical application, have the characteristics of amphiphilic nanostructure, easy surface modification, extended release time, good biocompatibility, etc. The liposomes are expected to overcome obstacles and effectively deliver drugs to the target site to improve ocular drug bioavailability. This review summarized the various controllable properties of liposomes for ocular delivery as well as the application and research progress of liposomes in various ocular diseases. In addition, we summarized the physiological barriers and routes of administration contained in eyes, as well as the prospects of liposomes in the treatment of ocular diseases.

Garlic-derived Exosomes Alleviate Osteoarthritis Through Inhibiting the MAPK Signaling Pathway

Osteoarthritis (OA) is the most common degenerative joint disease affecting millions of people worldwide. Garlic-derived exosomes (GDEs) are nanoparticles extracted from garlic that exhibit anti-inflammatory effects on other diseases, but the effect of GDEs on OA has not been elucidated. In this study, GDEs were extracted and characterized. Chondrocytes were treated with IL-1β and incubated with GDEs in vitro, and the expression of cartilage matrix components (collagen II and aggrecan) and matrix degrading enzymes (MMP3 and MMP9) was evaluated via Western blotting. Changes in the MAPK pathway was also examined using Western blotting. The transcriptomic changes associated with GDE intervention were evaluated using high-throughput RNA-seq method. In vivo, we used anterior cruciate ligament transection (ACLT) combined with destabilization of the medial meniscus (DMM) surgery to establish a mouse OA model, and GDEs was intraarticularly injected into the joint cavity. The therapeutic effect of GDE was evaluated by behavioral and histopathological analysis. The results showed that IL-1β treatment inhibited the expression of collagen II and aggrecan, and upregulated the expression of MMP3 and MMP9, while GDE intervention alleviated these effects. GDEs also inhibited the phosphorylation of ERK, JNK, and P38. In vivo, GDE alleviated the sensitivity to heat stimulation and altered walking gait in a mouse OA model. Histopathological analysis indicated that GDE intervention ameliorated joint destruction in the knee joint without obvious toxicity. The results proved that GDEs alleviated the progression of OA in vitro and in vivo, and may be a potential disease-modifying drug for OA.