Comparative study of nisoldipine-loaded nanostructured lipid carriers and solid lipid nanoparticles for oral delivery: preparation, characterization, permeation and pharmacokinetic evaluation

Augmented silver sulfadiazine nanostructured lipid carriers impregnated collagen sponge for promoting burn wound healing

Silver sulfadiazine (SSD) is a widely used antibacterial agent for burn wound treatment owing to its capability in re-epithelialization and wound healing. However, due to its low solubility, the need for an effective drug delivery system is mandatory. This study aimed to optimize SSD nanostructured lipid-based carriers (NLCs), incorporated in a collagen sponge form as an innovative topical dosage form for effective burn wound treatment. SSD-NLCs were prepared by applying Box-Behnken design and characterized in terms of particle size, zeta potential, and entrapment efficiency (EE). The optimized SSD-NLCs formula was selected and incorporated into a cross-linked collagen sponge and lyophilized for 24 h. The SSD-NLCs sponge morphological structure, porosity, swelling ratio, in vitro drug release profile and antibacterial activity were assessed. Furthermore, investigating the competitive inhibitory efficiency of SSD against para-aminobenzoic acid (PABA), the native ligand for the dihydropteroate synthetase enzyme based on the calculated binding free energy using the CB-Dock docking server was evaluated. Additionally, the wound healing activity and histopathological studies were evaluated on a second-degree burn wounds in a rat model. The optimized SSD-NLCs were spherical, possessing size of 115.69 ± 3.25 nm, EE% of 89.69 ± 1.36 % and a porosity of 71.22 %. Furthermore, the SSD-NLCs sponge showed an enhanced swelling ratio and improved antimicrobial activity compared to SSD. Finally, in vivo studies in rats showed that SSD-NLCs sponge are effective wound healing formulation owing to their ability to improve the quality of tissue regeneration without scars formation. Results showed that SSD-NLCs sponge can enhance the SSD efficacy in treatment of burn wounds. Further toxicological studies are still needed before clinical application.

Development and Optimization of Eberconazole Nanostructured Lipid Carrier Topical Formulations Based on the QbD Approach

Eberconazole nanostructured lipid carrier (EBR-NLC) 1% w/w optimization was done using the Quality by Design (QbD) approach, employing a 23 Full Factorial Design (FFD) for experimental planning, followed by thorough physico-chemical, in-vitro, and ex-vivo evaluations. The 23 FFD assessed the impact of total lipid amount, surfactant amount, and sonication time on critical quality attributes such as particle size and % entrapment efficiency. In-vitrorelease testing (IVRT) validation was performed using vertical diffusion cells. IVRT, a compendial technique by pharmacopoeias, was for performing semi-solid formulations analysis. The optimized EBR-NLC 1% w/w was characterized for assay, organic impurities, amplitude sweep, viscosity, IVRT, ex-vivo permeation testing, and skin retention. The validated IVRT technique was meeting the acceptance criteria of regulatory guidelines. The results showed that in-vitro release, ex-vivo permeation, and skin retention were significantly higher (P < 0.05) for the optimized EBR-NLC 1% w/w formulation compared to the innovator formulation (EBERNET® Cream 1% w/w). Applying QbD principles systematically facilitated the successful development and optimization of an EBR-NLC 1% w/w. The optimized EBR-NLC 1% w/w formulation proved to be a viable alternative, showing stability for at least six months under conditions of 40°C/75% RH and 30°C/75% RH.

Transdermal delivery of resveratrol loaded solid lipid nanoparticle as a microneedle patch: a novel approach for the treatment of Parkinson's disease

Parkinson's disease (PD), affecting millions of people worldwide and expected to impact 10 million by 2030, manifests a spectrum of motor and non-motor symptoms linked to the decline of dopaminergic neurons. Current therapies manage PD symptoms but lack efficacy in slowing disease progression, emphasizing the urgency for more effective treatments. Resveratrol (RSV), recognized for its neuroprotective and antioxidative properties, encounters challenges in clinical use for PD due to limited bioavailability. Researchers have investigated lipid-based nanoformulations, specifically solid lipid nanoparticles (SLNs), to enhance RSV stability. Oral drug delivery via SLNs faces obstacles, prompting exploration into transdermal delivery using SLNs integrated with microneedles (MNs) for improved patient compliance. In this study, an RSV-loaded SLNs (RSV -SLNs) incorporated into the MN patch was developed for transdermal RSV delivery to improve its stability and patient compliance. Characterization studies demonstrated favorable physical properties of SLNs with a sustained drug release profile of 78.36 ± 0.74%. The developed MNs exhibited mechanical robustness and skin penetration capabilities. Ex vivo permeation studies displayed substantial drug permeation of 68.39 ± 1.4% through the skin. In an in vivo pharmacokinetic study, the RSV-SLNs delivered through MNs exhibited a significant increase in Cmax, Tmax, and AUC0 - t values, alongside a reduced elimination rate in blood plasma in contrast to the administration of pure RSV via MNs. Moreover, an in vivo study showcased enhanced behavioral functioning and increased brain antioxidant levels in the treated animals. In-vivo skin irritation study revealed no signs of irritation till 24 h which permits long-term MNs application. Histopathological analysis showed notable changes in the brain regions of the rat, specifically the striatum and substantia nigra, after the completion of the treatment. Based on these findings, the development of an RSV-SLN loaded MNs (RSVSNLMP) patch presents a novel approach, with the potential to enhance the drug's efficiency, patient compliance, and therapeutic outcomes for PD, offering a promising avenue for advanced PD therapy.

Uncovering the Emerging Prospects of Lipid-based Nanoparticulate Vehicles in Lung Cancer Management: A Recent Perspective

Lung cancer, a leading cause of cancer-related deaths globally, is gaining research interest more than ever before. Owing to the burden of pathogenesis on the quality of life of patients and subsequently the healthcare system, research efforts focus on its management and amelioration. In an effort to improve bioavailability, enhance stability, minimize adverse effects and reduce the incidence of resistance, nanotechnological platforms have been harnessed for drug delivery and improving treatment outcomes. Lipid nanoparticles, in particular, offer an interesting clinical opportunity with respect to the delivery of a variety of agents. These include synthetic chemotherapeutic agents, immunotherapeutic molecules, as well as phytoconstituents with promising anticancer benefits. In addition to this, these systems are being studied for their usage in conjunction with other treatment strategies. However, their applications remain limited owing to a number of challenges, chiefly clinical translation. There is a need to address the scalability of such technologies, in order to improve accessibility. The authors aim to offer a comprehensive understanding of the evolution of lipid nanoparticles and their application in lung cancer, the interplay of disease pathways and their mechanism of action and the potential for delivery of a variety of agents. Additionally, a discussion with respect to results from preclinical studies has also been provided. The authors have also provided a well-rounded insight into the limitations and future perspectives. While the possibilities are endless, there is a need to undertake focused research to expedite clinical translation and offer avenues for wider applications in disease management.

Solid Lipid Nanoparticles for Pulmonary Delivery of Biopharmaceuticals: A Review of Opportunities, Challenges, and Delivery Applications

Biopharmaceuticals such as nucleic acids, proteins, and peptides constitute a new array of treatment modalities for chronic ailments. Invasive routes remain the mainstay of administering biopharmaceuticals due to their labile nature in the biological environment. However, it is not preferred for long-term therapy due to the lack of patient adherence and clinical suitability. Therefore, alternative routes of administration are sought to utilize novel biopharmaceutical therapies to their utmost potential. Nanoparticle-mediated pulmonary delivery of biologics can facilitate both local and systemic disorders. Solid lipid nanoparticles (SLNs) afford many opportunities as pulmonary carriers due to their physicochemical stability and ability to incorporate both hydrophilic and hydrophobic moieties, thus allowing novel combinatorial drug/gene therapies. These applications include pulmonary infections, lung cancer, and cystic fibrosis, while systemic delivery of biomolecules, like insulin, is also attractive for the treatment of chronic ailments. This Review explores physiological and particle-associated factors affecting pulmonary delivery of biopharmaceuticals. It compares the advantages and limitations of SLNs as pulmonary nanocarriers along with design improvements underway to overcome these limitations. Current research illustrating various SLN designs to deliver proteins, peptides, plasmids, oligonucleotides, siRNA, and mRNA is also summarized.

Several Applications of Solid Lipid Nanoparticles in Drug Delivery

Rapid progress is being made in the area of nanotechnology; solid lipid nanoparticles are currently at the forefront of research and development. They have the capability of becoming employed in an extensive number of applications, including the delivery of medications, clinical treatment, and research, in addition to uses in other areas of academic inquiry that could benefit from their utilisation. This article presents a thorough analysis of solid lipid nanoparticles, covering subjects such as their goals, preparation strategy, applications, advantages, and possible remedies for the issues that have been raised. This review provides a discussion of solid lipids that is both in-depth and comprehensive. Studies that investigate the manner in which SLNs are prepared and the routes via which they are administered are typical. Aspects concerning the route of administration of SLNs as well as the destiny of the carriers in vivo are also investigated in this paper.

Nanostructured Lipid Carriers to Enhance the Bioavailability and Solubility of Ranolazine: Statistical Optimization and Pharmacological Evaluations

Chronic stable angina pectoris is the primary indication for ranolazine (RZ), an anti-anginal drug. The drug has an anti-ischemic action that is unaffected by either blood pressure or heart rate. Due to the first-pass effect, the drug has a reduced bioavailability of 35 to 50%. The study emphasized developing a novel transdermal drug delivery system of nanostructured lipid carriers (NLCs) for delivering RZ. Many pharmaceutical companies employ lipid nanoparticles as biocompatible carriers for medicinal, cosmetic, and biochemical uses. These carriers are appropriate for many applications, such as topical, transdermal, parenteral, pulmonary, and oral administration, because of the large variety of lipids and surfactants that are readily available for manufacturing. RZ NLCs were made using high-pressure homogenization. Statistical analysis was utilized to find the best formula by varying the concentrations of Precirol ATO 5 (X1), oleic acid (X2), and Tween 80 (X3). Variables such as entrapment effectiveness (EE) (Y1), particle size (Y2), polydispersity index (PDI) (Y3), and zeta potential (Y4) were tested. A variety of tests were performed on the new formulation to ascertain how well it would be absorbed in the body. These tests included in vivo absorption studies, skin permeability assessments, in vitro drug release assessments, and physicochemical analyses. The particle size of RZ-NLCs was shown to be very small (118.4 ± 5.94 nm), with improved EE (88.39 ± 3.1%) and low ZP and PDI (-41.91 ± 0.38 and 0.118 ± 0.028). SEM and TEM analysis confirmed the structure of the NLCs and showed a smooth, spherical surface. Improved RZ-NLCs were used to create NLC gel, which was then tested for elasticity both physically and rheologically. The formulation's elasticity was investigated. Optimized RZ-NLCs and NLCG were found to have transdermal fluxes of 48.369 g/cm2/h and 38.383 g/cm2/h, respectively. These results showed that the transdermal delivery of RZ distribution through NLC's transdermal gel had more significant potential. According to in vivo experiments, the drug's bioavailability in Wistar rats increased when it was delivered through NLCs. The findings demonstrated that NLCs loaded with RZ successfully transported the RZ to the designated site with no interruptions and that a quadratic connection existed between the independent and dependent variables.

Perspectives on cutting-edge nanoparticulate drug delivery technologies based on lipids and their applications

Numerous nanotech arenas in therapeutic biology have recently provided a scientific platform to manufacture a considerable swath of unique chemical entities focusing on drugs. Recently, nanoparticulate drug delivery systems have emerged to deliver a specific drug to a specified site. Among all other carriers, lipids possess features exclusive to nanostructured dosage forms. The bioavailability of orally administered drugs is typically negatively affected by their poor water solubility, resulting from the unique chemical moieties introduced. Because of their unique advantages, lipid nanoparticles must become increasingly predictable as a robust delivery mechanism. The enhanced biopharmaceutical properties and significance of lipid-based targeting technologies such as liposomes, niosomes, solid lipid nanoparticles and micelles are highlighted in this review. Pharmaceutical implications of lipid nanocarriers for the transport and distribution of various therapeutic agents, such as biotechnological products and small pharmaceutical molecules, is a booming topic. Lipid nanoparticles as drug delivery systems have many appealing properties, including high biocompatibility, ease of preparation, tissue specificity, avoidance of reticuloendothelial systems, delayed drug release, scale-up feasibility, nontoxicity and targeted delivery. The use of lipid nanoparticles to enhance the transport of biopharmaceuticals is currently considered state-of-the-art. Similarly, we critically examine the upcoming guidelines that therapeutic scientists should handle.

An Overview of Nanostructured Lipid Carriers and its Application in Drug Delivery through Different Routes

Nanostructured Lipid Carriers (NLC) are nano-sized colloidal drug delivery system that contains a lipid mixture consisting of both solid and liquid lipids in their core. This Lipid-Based Nanosystem is introduced as a biocompatible, non-toxic, and safe nano-drug delivery system as compared to polymeric or metallic nanoparticles. Due to its safety, stability, and high drug loading capacity compared to other lipid-based nanocarriers, NLC gained the attention of researchers to formulate safe and effective drug carriers. The ability to increase drug solubility and permeability while encapsulating the drug in a lipidic shell makes them an ideal carrier for drug delivery through difficult-to-achieve routes. Surface modification of NLC and the use of various additives result in drug targeting and increased residence time. With such qualities, NLCs can be used to treat a variety of diseases such as cancer, infections, neurodegenerative diseases, hypertension, diabetes, and pain management. This review focuses on the recent developments being made to deliver the drugs and genes through different routes via these nanocarriers. Here, we also discuss about historical background, structure, types of NLC and commonly employed techniques for manufacturing lipid-based nanocarriers.

Solid Lipid Nanoparticles vs. Nanostructured Lipid Carriers: A Comparative Review

Solid-lipid nanoparticles and nanostructured lipid carriers are delivery systems for the delivery of drugs and other bioactives used in diagnosis, therapy, and treatment procedures. These nanocarriers may enhance the solubility and permeability of drugs, increase their bioavailability, and extend the residence time in the body, combining low toxicity with a targeted delivery. Nanostructured lipid carriers are the second generation of lipid nanoparticles differing from solid lipid nanoparticles in their composition matrix. The use of a liquid lipid together with a solid lipid in nanostructured lipid carrier allows it to load a higher amount of drug, enhance drug release properties, and increase its stability. Therefore, a direct comparison between solid lipid nanoparticles and nanostructured lipid carriers is needed. This review aims to describe solid lipid nanoparticles and nanostructured lipid carriers as drug delivery systems, comparing both, while systematically elucidating their production methodologies, physicochemical characterization, and in vitro and in vivo performance. In addition, the toxicity concerns of these systems are focused on.

Exploration of novel drug delivery systems in topical management of osteoarthritis

Osteoarthritis is one of the foremost disabling disorders in the world. There is no definitive treatment to prevent the progression of osteoarthritis. Hence, palliative treatment aims at minimizing pain, disability and improving function, performance and quality of life. Oral administration of nonsteroidal anti-inflammatory drug is associated with number of adverse effects and reduced therapeutic efficacy. Intra-articular injection has been the preferred route of drug administration. However, the clearance of drug from the arthritic site, risk of infections, cost and the pain associated with frequent injections make this route highly non-compliant to patients. Since osteoarthritis is a chronic condition which requires treatment for prolonged duration, there is an urgent need for another administration route which circumvents the hindrances linked with intra-articular route. Transdermal route across the skin locally at the osteoarthritis site could help in surpassing the disadvantages associated with intra-articular route. However, traversing skin barrier and reaching the chondrocytes with sufficient amount of the drug is extremely difficult. Nanocarrier-based approaches could hold an answer to the said shortcomings owing to their reduced size, targeting tunability and site specificity. In this article, we discuss the pathophysiology of osteoarthritis, molecular targets, and utilization of nanocarrier-based approaches to strategize the treatment of osteoarthritis in a new direction, i.e. topical delivery of nanocarriers in osteoarthritis.

Design and optimization of ganciclovir solid dispersion for improving its bioavailability

Development of new approaches for oral delivery of an existing antiviral drug aimed to enhance its permeability and hence bioavailability. Ganciclovir (GC) is an antiviral drug that belongs to class III in biopharmaceutical classification. The encapsulation of poorly absorbed drugs within nanosized particles offers several characteristics to drug due to their acquired surface properties. In the following study, the solvent evaporation technique was used to incorporate GC, within elegant nanosize particles using cyclodextrin and shellac polymers for enhancing its permeability and release pattern. Formulation variables were optimized using 2³ full factorial design. The prepared formulations were assessed for yield, particle size, content, and micromeritics behavior. The optimized formula (F6) was identified through differential scanning calorimetry and Fourier transform infrared. In vitro release and stability were also assessed. Pharmacokinetic parameters of optimized nano GC solid dispersion particles (NGCSD-F6) were finally evaluated. The optimized formula (F6) showed a mean particle size of 288.5 ± 20.7 nm, a zeta potential of about 23.87 ± 2.27, and drug content 95.77 ± 2.1%. The in vitro drug release pattern of F6 showed an initial burst release followed by a sustained release over the next 12 h. The optimized formula showed accepted stability upon storage at room and refrigerator temperatures for 6 months with good flowing properties (Carr's index = 18.28 ± 0.44). In vivo pharmacokinetic study in rabbits revealed 2.2 fold increases in the bioavailability of GC compared with commercial convention tablets. The study affords evidence for the success of the solid dispersion technique under specified conditions in improvement of bioavailability of GC.

Dual Drug Loaded Lipid Nanocarrier Formulations for Topical Ocular Applications

Introduction

Untreated ocular infections can damage the unique fine structures of the eye with possible visual impairments and blindness. Ciprofloxacin (CIP) ophthalmic solution is prescribed as first-line therapy in ocular bacterial infections. Natamycin (NT) ophthalmic suspension is one of the progenitors in ocular antifungal therapy. Nanostructured lipid carriers (NLCs) have been widely examined for ocular penetration enhancement and distribution to deeper ocular tissues. The objective of the current study was to prepare NLCs loaded with a combination of CIP and NT (CIP-NT-NLCs) and embed them in an in-situ gelling system (CIP-NT-NLCs-IG). This novel formulation will target the co-delivery of CIP and NT for the treatment of mixed ocular infections or as empirical treatment in case of limited access to healthcare diagnostic services.

Methods

CIP-NT-NLC and CIP-NT-NLC-IG formulations were evaluated based on physicochemical characteristics, in vitro release, and ex vivo transcorneal permeation studies and compared against commercial CIP and NT ophthalmic eye drops.

Results and Discussion

NLCs formulation (0.1% CIP and 0.3% NT) showed particle size, polydispersity index, and zeta potential of 196.2 ± 1.2 nm, 0.43 ± 0.06, and −28.1 ± 1.4 mV, respectively. Moreover, CIP-NT-NLCs showed entrapment efficiency of 80.9 ± 2.9 and 98.7 ± 1.9% for CIP and NT, respectively. CIP-NT-NLCs-IGformulation with 0.2% w/v gellan gum demonstrated the most favorable viscoelastic characteristics for ocular application. CIP-NT-NLCs and CIP-NT-NLCs-IG formulations exhibited a sustained release pattern for both drugs over 24 h. Moreover, CIP-NT-NLCs and CIP-NT-NLC-IG formulations showed 4.0- and 2.2-folds, and 5.0- and 2.5-folds enhancement in ex vivo transcorneal permeability of CIP and NT, respectively, compared to the control formulations.

Conclusion

The results suggest that this dual nanoparticulate-based in-situ gelling drug delivery system can serve as a promising topical delivery platform for the treatment of ocular infections.

Cyclodextrin Complexed Lipid Nanoparticles of Irbesartan for Oral Applications: Design, Development, and In Vitro Characterization

Irbesartan (IR) is an angiotensin II receptor antagonist drug with antihypertensive activity. IR bioavailability is limited due to poor solubility and first-pass metabolism. The current investigation aimed to design, develop, and characterize the cyclodextrin(s) (CD) complexed IR (IR-CD) loaded solid lipid nanoparticles (IR-CD-SLNs) for enhanced solubility, sustained release behavior, and subsequently improved bioavailability through oral administration. Based on phase solubility studies, solid complexes were prepared by the coacervation followed by lyophilization method and characterized for drug content, inclusion efficiency, solubility, and in vitro dissolution. IR-CD inclusion complexes demonstrated enhancement of solubility and dissolution rate of IR. However, the dissolution efficiency was significantly increased with hydroxypropyl-βCD (HP-βCD) inclusion complex than beta-CD (βCD). SLNs were obtained by hot homogenization coupled with the ultrasonication method with IR/HP-βCD inclusion complex loaded into Dynasan 112 and glycerol monostearate (GMS). SLNs were evaluated for physicochemical characteristics, in vitro release, differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD), and physical stability at room temperature for two months. The optimized SLNs formulation showed particle size, polydispersity index, zeta potential, assay, and entrapment efficiency of 257.6 ± 5.1 nm, 0.21 ± 0.03, -30.5 ± 4.1 mV, 99.8 ± 2.5, and 93.7 ± 2.5%, respectively. IR-CD-SLN and IR-SLN dispersions showed sustained release of IR compared to the IR-CD inclusion complexes. DSC results complimented PXRD results by the absence of IR endothermic peak. Optimized IR-CD complex, IR-SLN, and IR-CD-SLN formulations were stable for two months at room temperature. Thus, the current IR oral formulation may exhibit improved oral bioavailability and prolonged antihypertensive activity, which may improve therapeutic outcomes in the treatment of hypertension and heart failure.

In vitro dissolution considerations associated with nano drug delivery systems

Nano drug delivery systems (NDDS) offer promising solution for the translation of future nanomedicines. As bioavailability and therapeutic outcomes can be improved by altering the drug release from these NDDS, it becomes essential to thoroughly understand their drug release kinetics. Moreover, U.S. Food and Drug Administration requires critical evaluation of potential safety, efficacy, and public health impacts of nanomaterials. Spiraling up market share of NDDS has also stimulated the pharmaceutical industry to develop their cost-effective generic versions after the expiry of patent and associated exclusivity. However, unlike the conventional dosage forms, the in vivo disposition of NDDS is highly intricate and different from their in vitro behavior. Significant challenges exist in the establishment of in vitro-in vivo correlation (IVIVC) due to incomplete understanding of nanoparticles' in vivo biofate and its impact on in vitro experimental protocols. A rational design of dissolution may serve as quality and quantity control tool and help develop a meaningful IVIVC for favorable economic implications. Clinically relevant drug product specifications (critical quality attributes) can be identified by establishing a link between in vitro performance and in vivo exposure. In vitro dissolution may also play a pivotal role to understand the dissolution-mediated clearance and safety of NDDS. Prevalent in vitro dissolution methods for NDDS and their limitations are discussed in this review, among which USP 4 is gaining more interest recently. Researchers are working diligently to develop biorelevant in vitro release assays to ensure optimal therapeutic performance of generic versions of these NDDS. This article focuses on these studies and presents important considerations for the future development of clinically relevant in vitro release methods. This article is categorized under: Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine.

Targeting the Gut Mucosal Immune System Using Nanomaterials

The gastrointestinal (GI) tract is one the biggest mucosal surface in the body and one of the primary targets for the delivery of therapeutics, including immunotherapies. GI diseases, including, e.g., inflammatory bowel disease and intestinal infections such as cholera, pose a significant public health burden and are on the rise. Many of these diseases involve inflammatory processes that can be targeted by immune modulatory therapeutics. However, nonspecific targeting of inflammation systemically can lead to significant side effects. This can be avoided by locally targeting therapeutics to the GI tract and its mucosal immune system. In this review, we discuss nanomaterial-based strategies targeting the GI mucosal immune system, including gut-associated lymphoid tissues, tissue resident immune cells, as well as GI lymph nodes, to modulate GI inflammation and disease outcomes, as well as take advantage of some of the primary mechanisms of GI immunity such as oral tolerance.

Development of Self-Microemulsifying Drug Delivery System to Improve Nisoldipine Bioavailability: Cell Line and In Vivo Evaluations : Development of Self-Microemulsifying Drug Delivery System

The authors attempted to fabricate a novel lipid-based formulation of a lipophilic drug, nisoldipine (NISO). As NISO belongs to BCS class 2 drug, it suffers from low bioavailability (5%). Hence, the research was intended to ameliorate oral bioavailability of NISO via intestinal lymphatic transport. The NISO loaded self microemulsifying drug delivery system (SMEDDS) (NISO SMEDDS) was prepared using Peceol, Cremophor EL, and Transcutol HP. The Cremophor EL and Transcutol HP at 1:1 ratio showed maximum microemulsifying area, and average globule size was 16.78 ± 0.97 nm with PDI 0.121 ± 0.024. Cellular uptake studies (confocal microscopy and flow cytometry) using Caco-2 cells depicted higher fluorescence with coumarin-6 loaded SMEDDS as that of coumarin-6 solution which indicated deeper penetration. Mean fluorescence intensity (MFI) of coumarin-6 loaded SMEDDS was significantly improved (9.92-fold) in contrast to coumarin-6 solution. The NISO SMEDDS showed enhanced permeability (5.02 times) across Caco-2 cells compared to NISO suspension. The bioavailability improvement with NISO SMEEDS was 2.14 times relative to suspension, and lymphatic uptake was involved in oral absorption of NISO SMEDDS.

Design and Optimization of New Enteric Nanoparticles of Ceftriaxone for Oral Delivery: In vitro and in vivo Assessments

PURPOSE

Development of new strategies for oral delivery of existing antibiotics administered exclusively through intravenous route is one of the global priorities of pharmaceutical research. The encapsulation of these active pharmaceutical agents within nanosized natural products offers several traits due to their tunable surface properties. Ceftriaxone (CTX) is an injectable, third-generation cephalosporin that suffers poor oral bioavailability.

METHODS

In the present study, ionic gelation of two biopolymers, namely chitosan (CH) and shellac (SH), was implemented to consolidate CTX, within elegant nanoparticles (NPs) for oral administration that would increase its bioavailability and sustainability. Quality by design approach (23 full factorial design) was adopted to optimize CTX-loaded nanoparticles. The optimized formula (F2) was characterized through transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC). In vitro release behavior and stability study were also evaluated. Pharmacokinetic studies of enteric-coated hard gelatin capsules (HGCs) loaded with F2-NPs were finally assessed.

RESULTS

The optimized spherical F2-NPs had a mean particle size of 258 nm, zeta potential of about +30.1 and appreciable drug entrapment efficiency of 83%. The in vitro drug release profile of F2-NPs in pH 7.4 experienced biphasic configuration with an initial burst release for an hour, followed by a sustained release over 15 h with Higuchi model and non-Fickian diffusion mechanism (R2=0.9852). High stability upon storage at refrigerated and room temperature for 3 months and good flow properties (θ= 32.2 and HR= 1.13) of the optimized formula were also conferred. In vivo pharmacokinetic assessment in rabbits fruitfully displayed 92% absolute bioavailability of CTX.

CONCLUSION

The obtained results provide evidence for the potential combination of CH and SH in NPs preparation to enhance the oral bioavailability of CTX.

Preparation of Curcumin-Eudragit® E PO Solid Dispersions with Gradient Temperature through Hot-Melt Extrusion

Hot-melt extrusion (HME) has great advantages for the preparation of solid dispersion (SD), for instance, it does not require any organic solvents. Nevertheless, its application to high-melting-point and thermosensitive drugs has been rarely reported. In this study, thermally unstable curcumin (Cur) was used as a drug model. The HME process was systematically studied by adjusting the gradient temperature mode and residence time, with the content, crystallinity and dissolution of Cur as the investigated factors. The effects of barrel temperature, screw speed and cooling rate on HME were also examined. Solubility parameters and the Flory-Huggins method were used to evaluate the miscibility between Cur and carriers. Differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy, equilibrium solubility and in vitro and in vivo experiments were used to characterize and evaluate the results. An amorphous Cur SD was successfully obtained, increasing the solubility and release of Cur. In the optimal process, the mass ratio of Cur to Eudragit® E PO (EPO) was 1:4 and the barrel temperature was set at a gradient heating mode (130 °C-135 °C-140 °C-145 °C-150 °C-155 °C-160 °C) at 100 rpm. Related pharmacokinetic test results also showed the improved bioavailability of the drug in rats. In a pharmacodynamic analysis of Sprague-Dawley rats, the Cmax and the bioavailability of the Cur-EPO SD were 2.6 and 1.5 times higher than those of Cur, respectively. The preparation of the amorphous SD not only provided more solubility but also improved the bioavailability of Cur, which provides an effective way to improve the bioavailability of BCS II drugs.

Development and evaluation studies of Corylin loaded nanostructured lipid carriers gel for topical treatment of UV-induced skin aging

We prepared nanostructured lipid carriers (NLC) to promote skin permeation of Corylin so that it can increase its effect on photoaging. Corylin-NLCs were prepared and characterized based on morphology, particle size, zeta potentials, FTIR and DSC. In vitro, we assess the cytotoxicity and lactate dehydrogenase (LDH) of HaCaT cells irradiated by UVB. Expression of antioxidant enzymes was evaluated by commercial kits. The effects of Corylin-NLC on apoptosis were confirmed by flow cytometry and western blotting. In vivo, we use UV irradiated mouse as the oxidative stress model to assess the therapeutic effect of Corylin loaded NLC gel. We identified the Corylin-NLCs can significantly suppress the LDH release, decrease MDA content, increase in CAT, SOD, GSH-Px activity, increase the expression of Bcl-2/Bax protein and reduce the expression of cleaved caspase-3/caspase-3 protein on UVB induced HaCaT cells. The histopathological lesions were significantly improved and observably decreased MDA level, increase in antioxidant enzymes activity in serum of mice by pretreatment of Corylin-NLCs gel. Overall, this study proposes a promising strategy for improving the therapeutic efficacy of photoaging.

Attenuation of lipid levels in triton induced hyperlipidemia rats through rosuvastatin calcium nanoparticles: Pharmacokinetic and pharmacodynamic studies

The aim of this research was to study the effect of marketed tablet (Crestor®) powder suspension (MTPS) and nanoparticle formulation of rosuvastatin calcium (RC) on the pharmacokinetic (PK) and pharmacodynamic (PD) parameters in hyperlipidemia rats. The hyperlipidemia is induced by intraperitoneal injection of Triton-X-100 in 0.9 %w/v saline solution. The marketed tablet was dispersed into suspension. The RC loaded nanoparticles (RC-NPs) are prepared by homogenization method. The prepared RC-NP formulation was characterized for size, drug excipient compatibility and crystallization by differential scanning calorimeter (DSC), morphology by SEM, stability at room temperature, in-vitro dissolution and in-situ absorption in rats. Further, the pharmacokinetic and pharmacodynamic studies were conducted in hyperlipidemia rats. The size of the RC-NP formulation was found to be 183.4 ± 4.5 nm and to be nearly spherical by SEM. DSC studies revealed that no interaction and RC converted to amorphous form in RC-NP formulation. RC-NP formulation was physically and chemically stable over two months at room temperature. The drug release was found to be 25.8 ± 2.5 and 89.96 ± 2.8 % in five mins, respectively from MTPS and RC-NP formulations. The P_eff of MTPS and NP of RC was 1.8 ± 0.2 × 10^-5 and 2.7 ± 0.3 × 10^-5 cm/s, respectively. From the PK studies, the enhancement in the oral bioavailability was found to be 2.4-folds when compared to MTPS formulation and statistically significant (p < 0.05). PD study of RC-NP formulation in hyperlipidemic rats exhibited decrease in lipid profile for 24 h, while MTPS exhibited a decrease in lipid profile for 12 h. Therefore, the results conclusively demonstrate the nanoparticles of RC showed significant enhancement in the PK and PD parameters.

A One-Step Twin-Screw Melt Granulation with Gelucire 48/16 and Surface Adsorbent to Improve the Solubility of Poorly Soluble Drugs: Effect of Formulation Variables on Dissolution and Stability

Fenofibrate is an effective lipid-lowering drug; however, its poor solubility and high log p (5.2) result in insufficient absorption from the gastrointestinal tract, leading to poor bioavailability. In this study, a one-step continuous twin-screw melt granulation process was investigated to improve the solubility and dissolution of fenofibrate using Gelucire® 48/16 and Neusilin® US2 as the solubilizer and surface adsorbent, respectively. The formulations (granules) were prepared at different ratios of fenofibrate, Gelucire® 48/16, and Neusilin® US2 based on phase-solubility studies and characterized using dissolution, differential scanning calorimetry, powder X-ray diffraction, and scanning electron microscopy analyses and studies on flow properties. In the phase-solubility studies, a linear relation was observed between Gelucire® 48/16 concentration and the amount of fenofibrate dissolved. In contrast, the dissolution rate of the prepared formulations was independent of the fenofibrate: Gelucire® 48/16 ratio and dependent on the Neusilin® US2 levels in the formulation. Increasing Neusilin® US2 levels decreased the rate of dissolution of the granules but improved the stability of the tablets under storage at accelerated stability conditions. Interestingly, higher Gelucire® 48/16 levels in the granules resulted in tablets with a hard matrix, which slowed disintegration and dissolution. All formulations exhibited improved dissolution compared to pure fenofibrate.

Enhanced Pharmacokinetic Activity of Zotepine via Nanostructured Lipid Carrier System in Wistar Rats for Oral Application

BACKGROUND

Zotepine (ZT) is a substituted dibenzothiepine tricyclic molecule and second generation antipsychotic drug. It is available as the parenteral and oral solid dosage form, but, orally administered ZT has a poor oral bioavailability (10%) that might be due to either poor water solubility, high lipophilicity (Log P 4) and also first-pass hepatic metabolism.

OBJECTIVE

The oral bioavailability of ZT was improved by loading into a nanostructured lipid carriers (NLCs) system.

METHODS

Hot homogenization with probe sonication method was used for the preparation of ZT-NLCs formulations and characterized for an optimal system based on physicochemical characteristics and in vitro release. Differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) studies were used to confirm the crystalline nature and shape of the optimized ZT-NLC formulation. The physical stability of the optimized ZT-NLC formulation was evaluated at the refrigerator and room temperature over two months. Furthermore, in vivo pharmacokinetic (PK) studies of optimized ZT-NLC and ZT coarse suspension (ZT-CS) as control formulation, were conducted in male Wistar rats.

RESULTS

The optimized formulation of ZT-NLC showed Z-avg, PDI, ZP of 145.8 ± 2.5 nm, 0.18 ± 0.05, -31.6 ± 1.8 mV, respectively. In vitro release studies indicated the sustained release of ZT. DSC and XRD studies revealed the conversion of ZT into an amorphous form. SEM studies showed the spherical shape of the ZT-NLC formulation. PK studies showed 1.8-folds improvement (p<0.05) in oral bioavailability when compared with ZTCS formulation.

CONCLUSION

Overall, the results established that NLCs could be used as a new alternative delivery vehicle for the oral delivery of ZT.

Quality by Design Approach for Preparation of Zolmitriptan/Chitosan Nanostructured Lipid Carrier Particles - Formulation and Pharmacodynamic Assessment

Purpose

Zolmitriptan (ZT) is a selective serotonin agonist that is used for the treatment of migraine. It belongs to BCS class III with high solubility and low permeability. Besides, the drug is subjected to pre-systemic metabolism. Accordingly, new Zolmitriptan/chitosan nanostructured lipid carriers (ZT/CT NLCs) coated with Tween 80 (stealthy layer) have been developed to overcome such demerits.

Methods

The NLCs were developed by combining ultrasonication and double emulsion (w/o/w) techniques. The lipids were Gelucire and Labrasol. Herein, the quality by design (2³ full factorial design) was scrupulously followed, where critical process parameters and critical quality attributes were predefined. The optimized formulation (F8) was fully characterized with respect to entrapment efficiency (%EE), percentage yield (% yield), particle size, size distribution (PDI), zeta potential (ZP), morphological appearance (TEM). In vitro release, stability study and pharmacodynamic evaluations were also assessed. The optimized freeze dried formula was dispensed in in situ gelling hard gelatin capsule encompassing pectin and guar gum for further in vitro and pharmacodynamic evaluations.

Results

The optimized spherical nanoparticles experienced high percentage EE and yield (78.14% and 60.19%, respectively), low particle size and PDI (343.87 nm and 0.209, respectively), as well as high negative ZP (−25.5 mV). It showed good physical stability at refrigerated conditions. The NLCs dispensed in in situ gelling hard gelatin capsule comprising pectin and guar gum experienced sustained release for 30 h and significantly maintained the pharmacological effect in mice up to 8 h (p < 0.001).

Conclusion

ZT, a BCS class III drug that suffers from poor permeability and pre-systemic metabolism, was successfully maneuvered as nanostructured lipid carrier particles (NLCs). The incorporation of the NLCs in in situ gelling hard gelatin capsules fulfilled a dual function in increasing permeability, as well as sustaining the pharmacodynamic effect. This result would open new vistas in improving the efficacy of other class III drugs.

Solid Lipid Nanoparticles for Drug Delivery: Pharmacological and Biopharmaceutical Aspects

In the golden age of pharmaceutical nanocarriers, we are witnessing a maturation stage of the original concepts and ideas. There is no doubt that nanoformulations are extremely valuable tools for drug delivery applications; the current challenge is how to optimize them to ensure that they are safe, effective and scalable, so that they can be manufactured at an industrial level and advance to clinical use. In this context, lipid nanoparticles have gained ground, since they are generally regarded as non-toxic, biocompatible and easy-to-produce formulations. Pharmaceutical applications of lipid nanocarriers are a burgeoning field for the transport and delivery of a diversity of therapeutic agents, from biotechnological products to small drug molecules. This review starts with a brief overview of the characteristics of solid lipid nanoparticles and discusses the relevancy of performing systematic preformulation studies. The main applications, as well as the advantages that this type of nanovehicles offers in certain therapeutic scenarios are discussed. Next, pharmacokinetic aspects are described, such as routes of administration, absorption after oral administration, distribution in the organism (including brain penetration) and elimination processes. Safety and toxicity issues are also addressed. Our work presents an original point of view, addressing the biopharmaceutical aspects of these nanovehicles by means of descriptive statistics of the state-of-the-art of solid lipid nanoparticles research. All the presented results, trends, graphs and discussions are based in a systematic (and reproducible) bibliographic search that considered only original papers in the subject, covering a 7 years range (2013-today), a period that accounts for more than 60% of the total number of publications in the topic in the main bibliographic databases and search engines. Focus was placed on the therapeutic fields of application, absorption and distribution processes and current efforts for the translation into the clinical practice of lipid-based nanoparticles. For this, the currently active clinical trials on lipid nanoparticles were reviewed, with a brief discussion on what achievements or milestones are still to be reached, as a way of understanding the reasons for the scarce number of solid lipid nanoparticles undergoing clinical trials.

Colloidal lipid nanodispersion enriched hydrogel of antifungal agent for management of fungal infections: Comparative in-vitro, ex-vivo and in-vivo evaluation for oral and topical application

Ketoconazole (KZ) is broad spectrum antifungal drug, used for the treatment of fungal infections. KZ's clinical topical use has been associated with some adverse effects in healthy adults particularly local reactions, such as stinging, severe irritation, and pruritus. However, bioavailability of KZ after oral administration is low from tablets due to its low aqueous solubility. The objective of this investigation was development and characterization of KZ-containing solid lipid nanoparticles (KZ-SLNs) and SLN-containing hydrogel (KZ-SLN-H) for oral and topical delivery of KZ. KZ-SLNs were prepared using homogenization-sonication method. Optimal KZ-SLN formulation was selected based on physicochemical and in-vitro release studies. Optimized KZ-SLN converted to KZ-SLN hydrogel (KZ-SLN-H) using gelling polymers and optimized with rheological and in-vitro studies. Further, optimized KZ-SLN and KZ-SLN-H formulations evaluated for crystallinity, morphology, stability, ex-vivo and in-vivo pharmacokinetic (PK) studies in rats, comparison with KZ suspension (KZ-S) and KZ-S hydrogel (KZ-SH). Optimized KZ-SLN formulation showed desirable characters. KZ-SLN and KZ-SLN-H formulations exhibited spherical shape, converted to amorphous, sustained release behaviour and enhanced permeability (p < 0.05). Moreover, both formulations were stable for three months at 4 °C and 25 °C. PK studies revealed 1.9 and 1.5-folds, 3.5 and 2.8-folds enhancement of bioavailability of optimized KZ-SLN and KZ-SLN-H formulations (p < 0.05) compared with KZ-S and KZ-SH formulations, respectively. Overall, SLN and SLN-H formulations could be considered as an efficient delivery vehicles for KZ through oral and topical administration for better control over topical and systemic fungal infections.

Therapeutic Potential of Polyphenols-Loaded Polymeric Nanoparticles in Cardiovascular System

Numerous studies document an increased production of reactive oxygen species (ROS) with a subsequent decrease in nitric oxide (NO) bioavailability in different cardiovascular diseases, including hypertension, atherosclerosis, and heart failure. Many natural polyphenols have been demonstrated to decrease ROS generation and/or to induce the endogenous antioxidant enzymatic defense system. Moreover, different polyphenolic compounds have the ability to increase the activity/expression of endothelial nitric oxide synthase (eNOS) with a subsequent enhancement of NO generation. However, as a result of low absorption and bioavailability of natural polyphenols, the beneficial effects of these substances are very limited. Recent progress in delivering polyphenols to the targeted tissues revealed new possibilities for the use of polymeric nanoparticles in increasing the efficiency and reducing the degradability of natural polyphenols. This review focuses on the effects of different natural polyphenolic substances, especially resveratrol, quercetin, curcumin, and cherry extracts, and their ability to bind to polymeric nanoparticles, and summarizes the effects of polyphenol-loaded nanoparticles, mainly in the cardiovascular system.

Ciprofloxacin Loaded Nanostructured Lipid Carriers Incorporated into In-Situ Gels to Improve Management of Bacterial Endophthalmitis

Bacterial endophthalmitis (BE) is a potentially sight-threatening inflammatory reaction of the intraocular fluids or tissues caused by bacteria. Ciprofloxacin (CIP) eye drops are prescribed as first-line therapy in BE. However, frequent administration is necessary due to precorneal loss and poor ocular bioavailability. The objective of the current research was to prepare CIP containing nanostructured lipid carriers (CIP-NLCs) loaded an in situ gel system (CIP-NLC-IG) for topical ocular administration for enhanced and sustained antibacterial activity in BE treatment. CIP-NLCs were prepared by the hot homogenization method and optimized based on physicochemical characteristics and physical stability. The optimized CIP-NLC formulation was converted into CIP-NLC-IG with the addition of gellan gum as a gelling agent. Furthermore, optimized CIP-NLC and CIP-NLC-IG were evaluated for in vitro release and ex vivo transcorneal permeation studies, using commercial CIP ophthalmic solution (CIP-C) as the control. The optimized CIP-NLC formulation showed particle size, polydispersity index, zeta potential, assay and entrapment efficiency of 193.1 ± 5.1 nm, 0.43 ± 0.01, -32.5 ± 1.5 mV, 99.5 ± 5.5 and 96.3 ± 2.5%, respectively. CIP-NLC-IG with 0.2% w/v gellan gum showed optimal viscoelastic characteristics. The in vitro release studies demonstrated sustained release of CIP from CIP-NLC and CIP-NLC-IG formulations over a 24 h period. Transcorneal flux and permeability increased 4 and 3.5-fold, and 2.2 and 1.9-fold from CIP-NLC and CIP-NLC-IG formulations, respectively, when compared to CIP-C. The results demonstrate that CIP-NLC-IG could be considered as an alternate delivery system to prolong the residence time on the ocular surface after topical administration. Thus, the current CIP ophthalmic formulations may exhibit improved ocular bioavailability and prolonged antibacterial activity, which may improve therapeutic outcomes in the treatment of BE.

Lyophilized SLN of Cinnacalcet HCl: BBD enabled optimization, characterization and pharmacokinetic study

Objective: The objective of the present research is to formulate solid lipid nanoparticles (SLN) of CH to improve its oral bioavailability.Methods: Cinnacalcet hydrochloride (CH) exhibits poor oral bioavailability of 20 to 25% because of low aqueous solubility and first pass metabolism. The SLN formulations were optimized using Box-Behnken Design. SLN formulation was prepared using hot homogenization technique followed by ultra-sonication and evaluated. The optimized SLN formulation was lyophilized to improve the stability of the formulation further.Results: Compritol 888 ATO (COM), Soya lecithin (SL) and poloxamer 188 (POL) were selected as lipid, surfactant and co-surfactant respectively. For optimistaion, the desirable goal was fixed for variour responses vis-a-vis entrapment efficiency (EE), particle size (PS) and (time taken for diffusion of 85% drug) T85%. The optimized single dose of SLN obtained using BBD consisting of 30 mg of CH, 100 mg of COM, 150 mg of SL and 0.1% w/v of POL. The pharmacokinetic study revealed that optimized SLN and lyophilized SLN were found to increase the oral bioavailability nearly two times compared to an aqueous suspension of pure drug.Conclusion: Thus lyophilized SLN formulation explicated the potential of lipid-based nanoparticles as a potential carrier in improving the oral delivery and stability of CH.

Neuroprotective Effect of Ropinirole Lipid Nanoparticles Enriched Hydrogel for Parkinson's Disease: In Vitro, Ex Vivo, Pharmacokinetic and Pharmacodynamic Evaluation

Parkinson’s disease (rp) is a progressive neurodegenerative disorder. Ropinirole (RP) is a newer generation dopamine agonist used for the treatment of PD. It is prescribed as oral dosage form. However, limited oral bioavailability and frequent dosing limits the RP usage. The objective of the current investigation was to develop, optimize, evaluate pharmacokinetic (PK) and pharmacodynamic (PCD) activity of RP loaded solid lipid nanoparticles (RP-SLNs) and nanostructured lipid carriers (RP-NLCs) and containing hydrogel (RP-SLN-C and RP-NLC-C) formulations for improved oral and topical delivery. RP loaded lipid nanoparticles were optimized and converted to hydrogel using carbopol 934 as the gelling polymer. PK and PCD studies in haloperidol-induced PD were conducted in male Wistar rats. In vitro and ex vivo permeation studies showed sustained release profile and enhanced permeation compared with control formulations. Differential scanning calorimeter and X-ray diffraction studies revealed amorphous transformation; scanning electron microscope showed the spherical shape of RP in lipid nanoparticles. PK studies showed 2.1 and 2.7-folds enhancement from RP-SLN and RP-NLC from oral administration, 3.0 and 3.3-folds enhancement from RP-SLN-C and RP-NLC-C topical administration, compared with control formulations, respectively. RP-SLN-C and RP-NLC-C showed 1.4 and 1.2-folds topical bioavailability enhancement compared with RP-SLN and RP-NLC oral administration, respectively. PCD studies showed enhanced dopamine, glutathione, catalase levels and reduced lipid peroxidation levels, compared with the haloperidol-induced PD model. Overall, the results demonstrated that lipid nanoparticles and corresponding hydrogel formulations can be considered as an alternative delivery approach for the improved oral and topical delivery of RP for the effective treatment of PD.

Enhanced bioavailability and antihypertensive activity of nisoldipine loaded nanoemulsion: optimization, cytotoxicity and uptake across Caco-2 cell line, pharmacokinetic and pharmacodynamic studies

Objective: The present study explored the antihypertensive activity of nisoldipine in oil in water nanoemulsion to improve its oral bioavailability via intestinal lymphatic uptake.Methods: Nanoemulsion was prepared by ultrasonication technique using Peceol, Cremophor EL and Transcutol HP as oil, surfactant and cosurfactant respectively. Optimization was done employing 3² full factorial design. The developed formulation was assessed for in vitro,cell line, ex vivo and in vivo studies.Results: The experimental results indicated homogeneity of the nanoemulsion with globule size of 62.35 ± 2.55 nm and PDI value of 0.108 ± 0.01 with negative zeta potential (-26.2 ± 3.6 mV). Transmission electron microscopy showed spherical oil globules morphology. The in vitro diffusion study showed significant increase in drug release from NE formulations (98.51 ± 2.64%) as compared to plain drug dispersion (29.73 ± 2.15%) in 0.1 N HCl + 0.5% SLS medium. Moreover, higher quantitative and qualitative uptake of nanoemulsion via Caco-2 cells showed superior intestinal absorption and improved therapeutic activity of nisoldipine when compared to drug dispersion. Pharmacokinetic and pharmacodynamic study confirmed significantly (p ˂ 0.05) greater bioavailability and antihypertensive activity of nisoldipine nanoemulsion when compared to its dispersion. These results are visualized in abstract figure.Conclusion: Thus, prepared nanoemulsion showed potential as oral delivery system for nisoldipine with superior oral bioavailability and therapeutic efficacy over drug dispersion.

Improving the Oral Bioavailability of an Anti-Glioma Prodrug CAT3 Using Novel Solid Lipid Nanoparticles Containing Oleic Acid-CAT3 Conjugates

13a-(S)-3-pivaloyloxyl-6,7-dimethoxyphenanthro(9,10-b)-indolizidine (CAT3) is a novel oral anti-glioma pro-drug with a potent anti-tumor effect against temozolomide-resistant glioma in vivo. However, poor lipid solubility has limited the encapsulation efficacy during formulation development. Moreover, although the active metabolite of CAT3, 13a(S)-3-hydroxyl-6,7-dimethoxyphenanthro(9,10-b)-indolizidine (PF403), can penetrate the blood-brain barrier and approach the brain tissue with a 1000-fold higher anti-glioma activity than CAT3 in vitro, its bioavailability and Cmax were considerably low in plasma, limiting the anti-tumor efficacy. In this study, a novel oleic acid-CAT3 conjugate (OA-CAT3) was synthesized at the first time to increase the lipid solubility of CAT3. The OA-CAT3 loaded solid lipid nanoparticles (OA-CAT3-SLN) were constructed using an ultrasonic technique to enhance the bioavailability and Cmax of PF403 in plasma. Our results demonstrated that CAT3 was amorphous in the lipid core of OA-CAT3-SLN and the in vitro release was well controlled. Furthermore, the encapsulation efficacy and the zeta potential increased to 80.65 ± 6.79% and -26.7 ± 0.46 mV, respectively, compared to the normal CAT3 loaded SLN. As indicated by the high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) quantitation, the monolayer cellular transepithelial transport rate of OA-CAT3-SLN improved by 2.42-fold relied on cholesterol compared to the CAT3 suspension. Hence, the in vitro cell viability of OA-CAT3-SLN in C6 glioma cells decreased to 29.77% ± 2.13% and 10.75% ± 3.12% at 48 and 72 h, respectively. Finally, compared to the CAT3 suspension, the in vivo pharmacokinetics in rats indicated that the plasma bioavailability and Cmax of PF403 as afforded by OA-CAT3-SLN increased by 1.7- and 5.5-fold, respectively. Overall, the results indicate that OA-CAT3-SLN could be an efficacious delivery system in the treatment of glioma.

Preparation of Ergosterol-Loaded Nanostructured Lipid Carriers for Enhancing Oral Bioavailability and Antidiabetic Nephropathy Effects

In our previously studies, we confirmed that ergosterol could ameliorate diabetic nephropathy by suppressing the proliferation of mesangial cells and the accumulation of extracellular matrix (ECM). However, the therapeutic application of ergosterol may be confined due to poor aqueous solubility and low oral bioavailability. We aim to prepare ergosterol-loaded nanostructured lipid carriers (ERG-NLCs) to enhance the solubility and oral bioavailability of ergosterol. ERG-NLCs were prepared using glyceryl monostearate and decanoyl/octanoyl-glycerides by hot emulsification-ultrasonication method and characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) analysis, entrapment efficiency (EE), and drug loading (DL) capacity studies. The prepared ERG-NLCs were spherical, with particle size of 81.39 nm and negative zeta potential of 30.77 mV. Ergosterol was successfully encapsulated in NLCs with a high EE of 92.95% and a DL capacity of 6.51%. In pharmacokinetic study, C_max and AUC_0-∞ of ergosterol in ERG-NLCs were obviously enhanced, and the relative oral bioavailability of ERG-NLCs was 277.56% higher than that of raw ergosterol. Moreover, the in vitro pharmacodynamic study indicated that ERG-NLCs inhibited high-glucose-stimulated mesangial cells over proliferation and ECM accumulation more effectively compared to raw ergosterol. In conclusion, the validated ERG-NLCs showed that NLCs mediated delivery could be used as potential vehicle to enhance solubility, oral bioavailability and therapeutic efficacy of ergosterol.

In-situ Intestinal Absorption and Pharmacokinetic Investigations of Carvedilol Loaded Supersaturated Self-emulsifying Drug System

BACKGROUND

Carvedilol (CD), a non-selective beta-blocker, is indicated for the management of mild to moderate congestive heart failure. After oral administration, CD is rapidly absorbed with an absolute bioavailability of 18-25% because of low solubility and extensive first-pass metabolism.

OBJECTIVE

The present investigation focused on enhanced oral delivery of CD using supersaturated self-emulsifying drug delivery (SEDDS) system.

METHODS

Optimized SEDDS consisted of a blend of Oleic acid and Labrafil-M2125 as an oil-phase, Cremophor-RH40, polyethylene glycol-400 and HPMC-E5 as a surfactant, co-surfactant and supersaturation promoter respectively. Formulations were characterized for physical characteristics, invitro release in simulated and biorelevant dissolution media, intestinal permeability and bioavailability studies in Wistar rats. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) studies were used to confirm the crystalline nature and shape of the optimized formulation.

RESULTS

DSC and XRD, SEM studies showed that the drug was in amorphous form, and droplets were spherical in shape. Dissolution studies clearly showed distinct CD release in compendial and biorelevant dissolution media. The results from permeability and in-vivo studies depicted 2.2-folds and 3.2-folds increase in permeability and bioavailability, respectively from supersaturated SEDDS in comparison with control.

CONCLUSION

The results conclusively confirmed that the SEDDS formulation could be considered as a new alternative delivery vehicle for the oral supply of CD. Lay Summary: Carvedilol (CD) is a non-selective antihypertensive drug with poor oral bioavailability. Previously, various lipid delivery systems were reported with enhanced oral delivery. We developed suprsaturable SEDDS formulation with immediate onset of action. SEDDS formulation was developed and optimized as per the established protocols. The optimized SEDDS formulation was stable over three months and converted to solid and supersaturated SEDDS. The results from permeability and in-vivo studies demonstrated an enhancement in permeability and bioavailability from supersaturated SEDDS in comparison with control. The results conclusively confirmed that the SEDDS formulation could be considered as a new alternative delivery vehicle for the oral administration of CD.

Solid lipid matrix mediated nanoarchitectonics for improved oral bioavailability of drugs

Introduction: Solid matrix mediated lipid nanoparticle formulations (LNFs) retain some of the best features of ideal drug carriers necessary for improving the oral absorption and bioavailability (BA) of both hydrophilic and hydrophobic drugs. LNFs with solid matrices may be typically categorized into three major types of formulations, viz., solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs) and lipid-drug conjugate nanoparticles (LDC-NPs). Solid matrix based LNFs are, potentially, the most appropriate delivery systems for poorly water soluble drugs in need of improved drug solubility, permeability, absorption, or increased oral BA. In addition, LNFs as matrices are able to encapsulate both hydrophobic and hydrophilic drugs in a single matrix based on their excellent ability to form cores and shells. Interestingly, LNFs also act as delivery devices to impart chemical stability to various orally administered drugs. Areas covered: Aim of the review is to forecast the presentation of pharmacokinetic characteristics of solid lipid matrix based nanocarriers which are typically biocompatible, biodegradable and non-toxic carrier systems for efficient oral delivery of various drugs. Efficient delivery is broadly mediated by the fact that lipophilic drugs are readily soluble in lipidic substrates that are capable of permeating across the gut epithelium following oral administration, subsequently delivering the moiety of interest more efficiently across the gut mucosal membrane. This enhances the overall BA of many drugs facing oral delivery challenges by improving their pharmacokinetic profile. This article specifically focuses on the biopharmaceutical and pharmacokinetic aspects of such solid lipid matrix based nanoformulations and possible mechanisms for better drug absorption and improved BA following oral administration. It also briefly reviews methods to access the efficacy of LNFs for improving oral BA of drugs, regulatory aspects and some interesting lipid-derived commercial formulations, with a concluding remark. Expert opinion: LNFs enhance the overall BA of many drugs facing oral delivery challenges by improving their pharmacokinetic profile.

Simultaneous Monitoring of Amyloid-β (Aβ) Oligomers and Fibrils for Effectively Evaluating the Dynamic Process of Aβ Aggregation

Herein, we provide a proof of concept for a novel strategy that targets the assessment of the aggregation of amyloid-β (Aβ) by simultaneously determining its oligomers (Aβo) and fibrils (Aβf) in one analytical system. By fabricating and combining two immunosensors for Aβo and Aβf, respectively, we constructed a two-channel electrochemical system. The ratio of Aβf to Aβo was calculated and taken as a possible criterion for evaluating the extent of aggregation. Thereby, the presence of and transformation between oligomers and fibrils were accurately probed by incubating the Aβ monomer for different times and then calculating the ratios of Aβf to Aβo. The applicability of this method was further validated by tracking the dynamic progress of Aβ aggregation in the cerebrospinal fluid and tissues of Alzheimer's disease (AD) rats, which revealed that the ratio of Aβf to Aβo in rat brain gradually increased with the progression of AD, which was indicative of the severity of peptide aggregation during this process. Overall, this study represents the first example of a quantitative strategy for precisely evaluating the aggregation process that is related to pathological events in AD brain.

Solid Lipid Nanoparticles: Emerging Colloidal Nano Drug Delivery Systems

Solid lipid nanoparticles (SLNs) are nanocarriers developed as substitute colloidal drug delivery systems parallel to liposomes, lipid emulsions, polymeric nanoparticles, and so forth. Owing to their unique size dependent properties and ability to incorporate drugs, SLNs present an opportunity to build up new therapeutic prototypes for drug delivery and targeting. SLNs hold great potential for attaining the goal of targeted and controlled drug delivery, which currently draws the interest of researchers worldwide. The present review sheds light on different aspects of SLNs including fabrication and characterization techniques, formulation variables, routes of administration, surface modifications, toxicity, and biomedical applications.