A safety, tolerability, and pharmacokinetic study of a novel simvastatin silica-lipid hybrid formulation in healthy male participants

In Vitro and In Vivo Appraisal of Glycerylmonostearate/chitosan Hybrid Nanocapsules As Peroral Delivery System of Simvastatin

Simvastatin is one the most commonly used drugs for treatment of hypercholesterolemia but suffers from low bioavailability (about 5%) owing to poor aqueous solubility and extensive first pass metabolism. Glycerylmonostearate/chitosan hybrid olive oil cored nanocapsules were fabricated by a self-assembly method. Nine batches were successfully produced based on glycerylmonostearate/chitosan ratio and olive oil concentration. Selected formulation was and evaluated for oral bioavailability enhancement and pharmacodynamics. Glycerylmonostearate/chitosan ratio strongly influence the particle size and encapsulation of the formulations. Higher concentrations of olive oil produced larger particle size, heterogeneous distribution and higher encapsulation. Embedding of SIM in system matrix with existence in amorphous state was verified by DSC and FTIR tools. Selected formulation significantly enhanced SIM oral bioavailability with a 3.27-time higher in AUC when compared to SIM suspension. In addition, in vivo prolonged effect was verified by higher elimination half-life and mean residence time in plasma. Furthermore, pathological changes in liver and aorta associated with Poloxamer 704 injection have been mostly corrected. Serum lipid profile, liver function enzymes and oxidative stress were also restored. According to these results, glycerylmonostearate/chitosan hybrid olive oil cored nanocapsules proved to be a promising formulation strategy to significantly enhance SIM peroral bioavailability and therefore therapeutic efficacy.

Advancing atherosclerosis treatment: Drug encapsulation nanosystems and synthetic HDL nanoparticles

Atherosclerosis, characterized by plaque accumulation in arterial walls, remains a leading cause of cardiovascular disease. Current pharmacological treatments often lack efficacy in halting disease progression or addressing systemic complications. Nanotechnology offers promising solutions, including targeted drug delivery, enhanced bioavailability, and the ability to overcome biological barriers. This review explores the integration of drug-delivery nanosystems and synthetic high-density lipoprotein (HDL) nanoparticles into therapeutic strategies. Synthetic HDL nanoparticles not only serve as effective carriers for antidyslipidemic drugs but also act directly as functional HDL, improving lipid profiles and reducing systemic side effects. By enabling localized treatment and enhancing therapeutic precision, nanotechnology and synthetic HDL nanoparticles represent a paradigm shift in managing atherosclerosis, offering safer and more effective alternatives for preventing its life-threatening complications.

A promise of nose to brain delivery of bevacizumab intranasal sol-gel formulation substantiated in rat C6 glioma model

Glioblastoma is one of the rapidly spreading cancers, with its potent malignancy often linked to pronounced angiogenesis within tumors. To mitigate this vascularization profile, bevacizumab (Avastin®), a monoclonal antibody, has been utilized for its antiangiogenic activity. However, its effectiveness is hindered by challenges in crossing the blood-brain barrier and the risk of off-target organ toxicity. Delivering drugs directly from the nose to the brain through the olfactory or trigeminal nerves bypassing the blood-brain barrier offers enhanced bioavailability and a more precise targeting strategy. To overcome these challenges, we aimed to develop bevacizumab in situ gel loaded mesoporous silica nanoparticles for intranasal delivery and further examine their pharmacokinetic and pharmacodynamic characteristics. The intranasal gel of mesoporous silica nanoparticles loaded with bevacizumab was optimized and formulated using a factorial and quality by design approach. In the case of bevacizumab mesoporous silica nanoparticles, lower particle size and most negative zeta potential were selected as quality target product profiles which is important for drug loading on the mesoporous silica nanoparticles and also transport of these nanoparticles across the nasal mucosa to the brain. A design space with a multidimensional combination of input variables and process parameters has been demonstrated to assure quality. To optimize the design space and achieve the desired quality standards, the base catalyst and surfactant concentration were chosen as the critical process parameters, while particle size and zeta potential were identified as the critical quality attributes. The novel formulation was assessed for physicochemical parameters such as particle size, zeta potential, entrapment efficiency, appearance, color, consistency, and pH. Additionally, studies on in vitro release, ex vivo permeation, stability, nasal toxicity, organ safety, and bioavailability were conducted. The efficacy study was conducted in an orthotopic murine glioblastoma rat model in which C6 Luc cells were instilled in the striatum of the rat's brain. In vivo, bioluminescence imaging of brain tumors was carried out to observe the tumor regression after treatment with the intranasal and intravenous bevacizumab formulation. Biochemical parameters and histopathology were performed for organ safety studies. The optimized intranasal formulation exhibited an average particle size of 318.8 nm and a zeta potential of - 14.7 mV for the mesoporous silica nanoparticles. The formulation also demonstrated an entrapment efficiency of 91.34% and a loading capacity of 45.67%. Further pharmacokinetic studies revealed that the optimized intranasal bevacizumab formulation achieved a significantly higher brain concentration Cmax = 147.9 ng/ml, indicating improved bioavailability compared to rats administered with intravenous bevacizumab formulation (BEVATAS®), which had a Cmax of 127.2 ng/ml. Moreover, this nanoparticle formulation entirely mitigated systemic exposure to bevacizumab. Organ safety evaluation of different biochemical parameters and histopathological analyses revealed that the intranasal bevacizumab-treated group was showing less off-target organ toxicity compared to the group treated with intravenous bevacizumab formulation. Subsequently, the efficacy of this nanosystem was evaluated in an orthotopic glioblastoma rat model, monitoring tumor growth over time through in vivo bioluminescence imaging and assessing anti-angiogenic effects. Twenty-one days post-induction, mesoporous silica nanoparticles loaded with bevacizumab in situ gel exhibited a marked reduction in average bioluminescence radiance (4.39 × 103) from day 7 (1.35 × 107) emphasizing an enhanced anti-angiogenic effect compared to the group treated with intravenous bevacizumab formulation which showed a gradual decrease in average bioluminescence radiance (4.82 × 104) from day 7 (1.42 × 107). These results suggest that the proposed novel formulation of mesoporous silica nanoparticles loaded bevacizumab in situ gel could serve as a promising avenue to enhance glioblastoma treatment efficacy, thereby potentially improving patient quality of life and survival rates significantly. Furthermore, the success of this delivery method could open new avenues for treating other neurological disorders, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and stroke. By providing effective brain-targeted therapies, this approach has the potential to revolutionize treatment options and improve outcomes for a broad spectrum of neurological conditions.

Innovative Gastrointestinal Drug Delivery Systems: Nanoparticles, Hydrogels, and Microgrippers

Over the past decade, new technologies have emerged to increase intrinsic potency, enhance bioavailability, and improve targeted delivery of drugs. Most pharmaceutical formulations require multiple dosing due to their fast release and short elimination kinetics, increasing the risk of adverse events and patient non-compliance. Due to these limitations, enormous efforts have focused on developing drug delivery systems (DDSs) for sustained release and targeted delivery. Sustained release strategies began with pioneering research using silicone rubber embedding for small molecules and non-inflammatory polymer encapsulation for proteins or DNA. Subsequently, numerous DDSs have been developed as controlled-release formulations to deliver systemic or local therapeutics, such as small molecules, biologics, or live cells. In this review, we discuss the latest developments of DDSs, specifically nanoparticles, hydrogels, and microgrippers for the delivery of systemic or localized drugs to the gastrointestinal (GI) tract. We examine innovative DDS design and delivery strategies tailored to the GI tract's unique characteristics, such as its extensive length and anatomical complexity, varying pH levels and enzymatic activity across different sections, and intrinsic peristalsis. We particularly emphasize those designed for the treatment of inflammatory bowel disease (IBD) with in vivo preclinical studies.

Ordered Mesoporous Silica Delivering siRNA as Cancer Nanotherapeutics: A Comprehensive Review

Nanosized mesoporous silica has emerged as a promising flexible platform delivering siRNA for cancer treatment. This ordered mesoporous nanosized silica provides attractive features of well-defined and tunable porosity, structure, high payload, and multiple functionalizations for targeted delivery and increasing biocompatibility over other polymeric nanocarriers. Moreover, it also overcomes the lacunae associated with traditional administration of drugs. Chemically modified porous silica matrix efficiently entraps siRNA molecules and prevents their enzymatic degradation and premature release. This Review discusses the synthesis of silica using the sol-gel approach and the advantages with different silica mesostructure. Herein, the factors affecting the synthesis of silica at nanometer scale, shape, porosity and nanoparticle surface modification are also highlighted to attain the desired nanostructured silica carriers. Additional emphasis is given to chemically modified silica delivering siRNA, where the silica nanoparticle surface was modified with different chemical moieties such as amine modified with (3-aminoropyl) triethoxysilane, polyethylenimine, chitosan, poly(ethylene glycol), and cyclodextrin polymer modification to attain high therapeutic loading, improved dispersibility and biocompatibility. Upon systemic administration, ordered mesoporous nanosized silica encounters blood cells, immune cells, and organs mainly of the reticuloendothelial system (RES). Thereby, biocompatibility and biodistribution of silica based nanocarriers are deliberated to design principles for smart and efficacious nanostructured silica-siRNA carriers and their clinical trial status. This Review further reports the future scopes and challenges for developing silica nanomaterial as a promising siRNA delivery vehicle demanding FDA approval.

Lactoferrin Reduces Surfactant Content in the Self-Emulsifying Drug Delivery System

Self-emulsifying drug delivery systems (SEDDSs) can effectively be employed to formulate drugs with poor oral bioavailability due to low aqueous solubility and high first-pass metabolism. High surfactant content is an existing challenge toward the successful application of SEDDS. A SEDDS is developed with lactoferrin, a natural emulsifier to reduce the Tween content of a fenofibrate (FEN) formulation. FEN SEDDS (SEDDS without lactoferrin) and FEN Lf-SEDDS (SEDDS with lactoferrin) were developed with 30% and 21% Tween content, respectively. Both formulations containing Crodamol GTCC as a lipid component were thermodynamically stable. No significant difference was observed in zeta potential (-9.25 to -12.63 mV), drug content (>85%), and percentage transmittance (>99%) between the two formulations. FEN Lf-SEDDS resulted in higher viscosity and larger particle size than FEN SEDDS. Solidified SEDDS with Aerosil 200 significantly improved in vitro drug release from both formulations than pure FEN. However, FEN SEDDS and FEN Lf-SEDDS did not show a significant difference in cumulative percent release or dissolution efficiency at 120 min. It can be concluded that lactoferrin containing SEDDS with 27% lesser synthetic surfactants (Tween 80 and Span 80) can result in similar physicochemical characteristics. Oral pharmacokinetic study of FEN Lf-SEDDS in a rat model resulted in 1.3 and 5.5 times higher relative bioavailability than marketed product and pure drug, respectively. The addition of lactoferrin could substitute synthetic surfactants in self-emulsifying drug delivery systems significantly.

Polymeric nanocomposite hydrogel scaffold for jawbone regeneration: The role of rosuvastatin calcium-loaded silica nanoparticles

Bones are subject to different types of damages ranging from simple fatigue to profound defects. In serious cases, the endogenous healing mechanism is not capable of healing the damage or restoring the normal structure and function of the bony tissue. The aim of this research was to achieve a sustained delivery of rosuvastatin and assess its efficacy in healing bone tissue damage. Rosuvastatin was entrapped into silica nanoparticles and the system was loaded into an alginate hydrogel to be implanted in the damaged tissue. Silica nanoparticles were formulated based on a modified Stöber technique and alginate hydrogel was prepared via sprinkling alginate onto silica nanoparticle dispersion followed by addition of CaCl2 to promote crosslinking and hydrogel rigidification. The selected nanoparticle formulation possessed high % drug content (100.22± 0.67%), the smallest particle size (221.00± 7.30 nm) and a sustained drug release up to 4 weeks (98.72± 0.52%). The fabricated hydrogel exhibited a further delay in drug release (81.52± 4.81% after 4 weeks). FT-IR indicated the silica nanoparticle formation and hydrogel crosslinking. SEM visualized the porous and dense surface of hydrogel. In-vivo testing on induced bone defects in New Zealand rabbits revealed the enhanced rate of new bone tissue formation, its homogeneity in color as well as similarity in structure to the original tissue.

Use of Silica Nanoparticles for Drug Delivery in Cardiovascular Disease

PURPOSE

Cardiovascular disease (CVD) is the leading cause of death worldwide. The current CVD therapeutic drugs require long-term treatment with high doses, which increases the risk of adverse effects while offering only marginal treatment efficacy. Silica nanoparticles (SNPs) have been proven to be an efficient drug delivery vehicle for numerous diseases, including CVD. This article reviews recent progress and advancement in targeted delivery for drugs and diagnostic and theranostic agents using silica nanoparticles to achieve therapeutic efficacy and improved detection of CVD in clinical and preclinical settings.

METHODS

A search of PubMed, Scopus, and Google Scholar databases from 1990 to 2023 was conducted. Current clinical trials on silica nanoparticles were identified through ClinicalTrials.gov. Search terms include silica nanoparticles, cardiovascular diseases, drug delivery, and therapy.

FINDINGS

Silica nanoparticles exhibit biocompatibility in biological systems, and their shape, size, surface area, and surface functionalization can be customized for the safe transport and protection of drugs in blood circulation. These properties also enable effective drug uptake in specific tissues and controlled drug release after systemic, localized, or oral delivery. A range of silica nanoparticles have been used as nanocarrier for drug delivery to treat conditions such as atherosclerosis, hypertension, ischemia, thrombosis, and myocardial infarction.

IMPLICATIONS

The use of silica nanoparticles for drug delivery and their ongoing development has emerged as a promising strategy to improve the effectiveness of drugs, imaging agents, and theranostics with the potential to revolutionize the treatment of CVD.

Oxygen-Deficient Bioceramics: Combination of Diagnosis, Therapy, and Regeneration

The journey of ceramics in medicine has been synchronized with an evolution from the first generation-alumina, zirconia, etc.-to the third -3D scaffolds. There is an up-and-coming member called oxygen-deficient or colored bioceramics, which have recently found their way through biomedical applications. The oxygen vacancy steers the light absorption toward visible and near infrared regions, making the colored bioceramics multifunctional-therapeutic, diagnostic, and regenerative. Oxygen-deficient bioceramics are capable of turning light into heat and reactive oxygen species for photothermal and photodynamic therapies, respectively, and concomitantly yield infrared and photoacoustic images. Different types of oxygen-deficient bioceramics have been recently developed through various synthesis routes. Some of them like TiO2- x , MoO3- x , and WOx have been more investigated for biomedical applications, whereas the rest have yet to be scrutinized. The most prominent advantage of these bioceramics over the other biomaterials is their multifunctionality endowed with a change in the microstructure. There are some challenges ahead of this category discussed at the end of the present review. By shedding light on this recently born bioceramics subcategory, it is believed that the field will undergo a big step further as these platforms are naturally multifunctional.

Glutathione-Exhausting Nanoprobes for NIR-II Fluorescence Imaging-Guided Surgery and Boosting Radiation Therapy Efficacy via Ferroptosis in Breast Cancer

Breast-conserving surgery (BCS) is the standard of care for early breast cancer patients, while the high ratio of reoperation is still a challenge due to inaccurate margin assessments. In patients with locally advanced or advanced breast cancer, radiotherapy is an important treatment for local control or improvement of quality of life. However, enhancing sensitization to radiotherapy is an unmet medical need. To solve the above clinical predicaments, a glutathione (GSH) exhausting virus-like silicon dioxide nanoprobe with Gd coating and folic acid (FA) modification is designed. After loading ICG in the mesopores, the VGd@ICG-FA probe efficiently targets tumor cells with high resolution, due to its virus-like morphology and folate acid anchoring. Especially, the fabricated nanoprobe enables the identification of tiny cancers and navigates precise surgery under NIR-II fluorescence imaging. Moreover, after the nanoprobes enter into the cytoplasm of cancer cells, tetrasulfide linkages in the silica framework are broken under the triggering of high GSH concentrations. In turn, the broken framework exhausts GSH to disrupt intracellular reactive oxygen species (ROS) homeostasis, and Gd produces more ROS under radiotherapy, further activating ferroptosis, and resulting in the enhancement of radiotherapy in breast cancer. Therefore, our nanoprobe exhibits tremendous potential as a NIR-II fluorescence imaging agent with no systematic side effects for precise cancer surgery and nanotherapeutics for boosting radiation sensitivity in future clinical translation of breast cancer.

Recent Advances in the Microencapsulation of Essential Oils, Lipids, and Compound Lipids through Spray Drying: A Review

In recent decades, the microcapsules of lipids, compound lipids, and essential oils, have found numerous potential practical applications in food, textiles, agricultural products, as well as pharmaceuticals. This article discusses the encapsulation of fat-soluble vitamins, essential oils, polyunsaturated fatty acids, and structured lipids. Consequently, the compiled information establishes the criteria to better select encapsulating agents as well as combinations of encapsulating agents best suited to the types of active ingredient to be encapsulated. This review shows a trend towards applications in food and pharmacology as well as the increase in research related to microencapsulation by the spray drying of vitamins A and E, as well as fish oil, thanks to its contribution of omega 3 and omega 6. There is also an increase in articles in which spray drying is combined with other encapsulation techniques, or modifications to the conventional spray drying system.

Toxicity evaluation of silica nanoparticles for delivery applications

Silica nanoparticles (SiNPs) are being explored as nanocarriers for therapeutics delivery, which can address a number of intrinsic drawbacks of therapeutics. To translate laboratory innovation into clinical application, their potential toxicity has been of great concern. This review attempts to comprehensively summarize the existing literature on the toxicity assessment of SiNPs. The current data suggest that the composition of SiNPs, their physicochemical properties, their administration route, their frequency and duration of administration, and the sex of animal models are related to their tissue and blood toxicity, immunotoxicity, and genotoxicity. However, the correlation between in vitro and in vivo toxicity has not been well established, mainly because both the in vitro and the in vivo-dosed quantities are unrealistic. This article also discusses important factors to consider in the toxicology of SiNPs and current approaches to reducing their toxicity. The aim is to give readers a better understanding of the toxicology of silica nanoparticles and to help identify key gaps in knowledge and techniques.

Mesoporous Silica Nanoparticles as a Potential Nanoplatform: Therapeutic Applications and Considerations

With advances in nanotechnology, nanoparticles have come to be regarded as carriers of therapeutic agents and have been widely studied to overcome various diseases in the biomedical field. Among these particles, mesoporous silica nanoparticles (MSNs) have been investigated as potential nanocarriers to deliver drug molecules to various target sites in the body. This review introduces the physicochemical properties of MSNs and synthesis procedures of MSN-based nanoplatforms. Moreover, we focus on updating biomedical applications of MSNs as a carrier of therapeutic or diagnostic cargo and review clinical trials using silica-nanoparticle-based systems. Herein, on the one hand, we pay attention to the pharmaceutical advantages of MSNs, including nanometer particle size, high surface area, and porous structures, thus enabling efficient delivery of high drug-loading content. On the other hand, we look through biosafety and toxicity issues associated with MSN-based platforms. Based on many reports so far, MSNs have been widely applied to construct tissue engineering platforms as well as treat various diseases, including cancer, by surface functionalization or incorporation of stimuli-responsive components. However, even with the advantageous aspects that MSNs possess, there are still considerations, such as optimizing physicochemical properties or dosage regimens, regarding use of MSNs in clinics. Progress in synthesis procedures and scale-up production as well as a thorough investigation into the biosafety of MSNs would enable design of innovative and safe MSN-based platforms in biomedical fields.

Tissue Engineering and Targeted Drug Delivery in Cardiovascular Disease: The Role of Polymer Nanocarrier for Statin Therapy

Atherosclerosis-related coronary artery disease (CAD) is the leading cause of mortality and morbidity worldwide. This requires effective primary and secondary prevention in reducing the complications related to CAD; the regression or stabilization of the pathology remains the mainstay of treatment. Statins have proved to be the most effective treatment in reducing adverse effects, but there are limitations related to the administration and achievement of effective doses as well as side effects due to the lack of target-related molecular specificity. The implemented technological steps are polymers and nanoparticles for the administration of statins, as it has been seen how the conjugation of drug delivery systems (DDSs) with statins increases bioavailability by circumventing the hepatic-renal filter and increases the related target specificity, enhancing their action and decreasing side effects. Reduction of endothelial dysfunction, reduced intimal hyperplasia, reduced ischemia-reperfusion injury, cardiac regeneration, positive remodeling in the extracellular matrix, reduced neointimal growth, and increased reendothelialization are all drug-related effects of statins enhanced by binding with DDSs. Recent preclinical studies demonstrate how the effect of statins stimulates the differentiation of endogenous cardiac stem cells. Poly-lactic-co-glycolic acid (PLGA) seems to be the most promising DDS as it succeeds more than the others in enhancing the effect of the bound drug. This review intends to summarize the current evidence on polymers and nanoparticles for statin delivery in the field of cardiovascular disease, trying to shed light on this topic and identify new avenues for future studies.

Current status of silica-based nanoparticles as therapeutics and its potential as therapies against viruses

In the past decade, interest in nanoparticles for clinical indications has been steadily gaining traction. Most recently, Lipid Nanoparticles (LNP) have been used successfully to construct the SARS-CoV-2 mRNA vaccines for rapid pandemic response. Similarly, silica is another nanomaterial which holds much potential to create nanomedicines against pathogens of interest. One major advantage of silica-based nanoparticles is its crystalline and highly ordered structure, which can be specifically tuned to achieve the desired properties needed for clinical applications. Increasingly, clinical research has shown the potential of silica nanoparticles not only as an antiviral, but also its ability as a delivery system for antiviral small molecules and vaccines against viruses. Silica has an excellent biosafety profile and has been tested in several early phase clinical trials since 2012, demonstrating good tolerability and minimal reported side effects. In this review, we discuss the clinical development of silica nanoparticles to date and identify the gaps and potential pitfalls in its path to clinical translation.

From Synthetic Route of Silica Nanoparticles to Theranostic Applications

The advancements in nanotechnology have quickly developed a new subject with vast applications of nanostructured materials in medicine and pharmaceuticals. The enormous surface-to-volume ratio, ease of surface modification, outstanding biocompatibility, and, in the case of mesoporous nanoparticles, the tunable pore size make the silica nanoparticles (SNPs) a promising candidate for nano-based medical applications. The preparation of SNPs and their contemporary usage as drug carriers, contrast agents for imaging, carrier of photosensitizers (PS) in photodynamic, as well as photothermal treatments are intensely discussed in this review. Furthermore, the potential harmful responses of silica nanoparticles are reviewed using data obtained from in vitro and in vivo experiments conducted by several studies. Moreover, we showcase the engineering of SNPs for the theranostic applications that can address several intrinsic limitations of conventional therapeutics and diagnostics. In the end, a personal perspective was outlined to state SNPs’ current status and future directions, focusing on SNPs’ significant potentiality and opportunities.

Bio-enabling strategies to mitigate the pharmaceutical food effect: a mini review

The concomitant administration of oral drugs with food can result in significant changes in bioavailability, leading to variable pharmacokinetics and considerable clinical implications, such as over- or under-dosing. Consequently, there is increasing demand for bio-enabling formulation strategies to reduce variability in exposure between the fasted and fed state and/or mitigate the pharmaceutical food effect. The current review critically evaluates technologies that have been implemented to overcome the positive food effects of pharmaceutical drugs, including, lipid-based formulations, nanosized drug preparations, cyclodextrins, amorphisation and solid dispersions, prodrugs and salts. Additionally, improved insight into preclinical models for predicting the food effect is provided. Despite the wealth of research, this review demonstrates that application of optimal formulation strategies to mitigate the positive food effects and the evaluation in preclinical models is not a universal approach, and improved standardisation of models to predict the food effects would be desirable. Ultimately, the successful reformulation of specific drugs to eliminate the food effect provides a panoply of advantages for patients with regard to clinical efficacy and compliance.

Nanoarchitectured prototypes of mesoporous silica nanoparticles for innovative biomedical applications

Despite exceptional morphological and physicochemical attributes, mesoporous silica nanoparticles (MSNs) are often employed as carriers or vectors. Moreover, these conventional MSNs often suffer from various limitations in biomedicine, such as reduced drug encapsulation efficacy, deprived compatibility, and poor degradability, resulting in poor therapeutic outcomes. To address these limitations, several modifications have been corroborated to fabricating hierarchically-engineered MSNs in terms of tuning the pore sizes, modifying the surfaces, and engineering of siliceous networks. Interestingly, the further advancements of engineered MSNs lead to the generation of highly complex and nature-mimicking structures, such as Janus-type, multi-podal, and flower-like architectures, as well as streamlined tadpole-like nanomotors. In this review, we present explicit discussions relevant to these advanced hierarchical architectures in different fields of biomedicine, including drug delivery, bioimaging, tissue engineering, and miscellaneous applications, such as photoluminescence, artificial enzymes, peptide enrichment, DNA detection, and biosensing, among others. Initially, we give a brief overview of diverse, innovative stimuli-responsive (pH, light, ultrasound, and thermos)- and targeted drug delivery strategies, along with discussions on recent advancements in cancer immune therapy and applicability of advanced MSNs in other ailments related to cardiac, vascular, and nervous systems, as well as diabetes. Then, we provide initiatives taken so far in clinical translation of various silica-based materials and their scope towards clinical translation. Finally, we summarize the review with interesting perspectives on lessons learned in exploring the biomedical applications of advanced MSNs and further requirements to be explored.

Role of Silica Intrawall Microporosity on Abiraterone Acetate Solubilization and In Vivo Oral Absorption

SBA-15 mesoporous silica (MPS) has been widely used in oral drug delivery; however, it has not been utilized for solidifying lipid-based formulations, and the impact of their characteristic intrawall microporosity remains largely unexplored. Here, we derive the impact of the MPS microporosity on the in vitro solubilization and in vivo oral pharmacokinetics of the prostate cancer drug abiraterone acetate (AbA) when coencapsulated along with medium chain lipids into the pores. AbA in lipid (at 80% equilibrium solubility) was imbibed within a range of MPS particles (with comparable morphology and mesoporous structure but contrasting microporosity ranging from 0-247 m²/g), and their solid-state properties were characterized. Drug solubilization studies during in vitro lipolysis revealed that microporosity was the key factor in facilitating AbA solubilization by increasing the surface area available for drug-lipid diffusion. Interestingly, microporosity hindered hydrolysis of AbA to its active metabolite, abiraterone (Ab), under simulated intestinal conditions. This unique relationship between microporosity and AbA/Ab aqueous solubilization behavior was hypothesized to have significant implications on the subsequent bioavailability of the active metabolite. In vivo oral pharmacokinetics studies in male Sprague-Dawley rats revealed that MPS with moderate microporosity attained the highest relative bioavailability, while poor in vitro-in vivo correlations (IVIVC) existed between in vitro drug solubilization during lipolysis and in vivo AUC. Despite this, a reasonable IVIVC was established between the in vitro solubilization and in vivo C_max, providing evidence for an association between silica microporosity and oral drug absorption.

Silica-Based Stimuli-Responsive Systems for Antitumor Drug Delivery and Controlled Release

The administration of cytotoxic drugs in classical chemotherapy is frequently limited by water solubility, low plasmatic stability, and a myriad of secondary effects associated with their diffusion to healthy tissue. In this sense, novel pharmaceutical forms able to deliver selectively these drugs to the malign cells, and imposing a space-time precise control of their discharge, are needed. In the last two decades, silica nanoparticles have been proposed as safe vehicles for antitumor molecules due to their stability in physiological medium, high surface area and easy functionalization, and good biocompatibility. In this review, we focus on silica-based nanomedicines provided with specific mechanisms for intracellular drug release. According to silica nature (amorphous, mesostructured, and hybrids) nanocarriers responding to a variety of stimuli endogenously (e.g., pH, redox potential, and enzyme activity) or exogenously (e.g., magnetic field, light, temperature, and ultrasound) are proposed. Furthermore, the incorporation of targeting molecules (e.g., monoclonal antibodies) that interact with specific cell membrane receptors allows a selective delivery to cancer cells to be carried out. Eventually, we present some remarks on the most important formulations in the pipeline for clinical approval, and we discuss the most difficult tasks to tackle in the near future, in order to extend the use of these nanomedicines to real patients.

Comparative Bioavailability Study of Solid Self-Nanoemulsifying Drug Delivery System of Fenofibric Acid in Healthy Male Subjects

OBJECTIVE

This study aimed to evaluate the effect of solid self-nanoemulsifying drug delivery system (S-SNEDDS) formation on the bioavailability of fenofibric acid.

SUBJECT AND METHODS

Three formulations of fenofibric acid, namely, S-SNEDDS containing medium-chain triglyceride (FS1), S-SNEDDS containing long-chain triglyceride (FS2), and FSt as tablet of innovator product, were used in this study. Bioavailability study was conducted in 12 Indonesian healthy male subjects after a single-dose administration of each formulation with three-way crossover design. Blood samples were collected from 0 to 72 h after drug administration and then analyzed using the high-performance liquid chromatography method. Data were statistically analyzed using the ANOVA and the Wilcoxon signed-rank test using a p value of 0.05. Dissolution test was carried out with USP dissolution apparatus using three medium (pH 1.2, 4.5 and 6.8).

RESULTS

The rates of absorption of fenofibric acid from S-SNEDDS FS1 and FS2 were significantly increased about 1.78 and 2.40 times, respectively, relative to FSt. Tmax values of FS1 and FS2 were shorter than FSt, namely, 0.96 ± 0.438 h (FS1), 0.71 ± 0.445 h (FS2), and 1.71 ± 0.840 h (FSt), respectively. Meanwhile, the Cmax and AUC values of FS1, FS2, and FSt were found to be not significantly different with a p value of >0.05. S-SNEDDS formation increased the dissolution rate in acid medium.

CONCLUSIONS

S-SNEDDS increased the dissolution rate in acid medium and absorption rate of fenofibric acid but did not increase the extent of fenofibric acid absorption.

Harnessing the potential of nanostructured formulations to mimic the food effect of lurasidone

Lurasidone is an important antipsychotic drug indicated for the treatment of schizophrenia and bipolar disorder, with an oral bioavailability of 9-19% owing to its poor aqueous solubility. Additionally, lurasidone exhibits a 2-fold positive food effect, such that patients must administer their medication with a meal, leading to significant non-compliance. The aim of this research was to evaluate the in vitro and in vivo performance of lurasidone when engineered as nanostructured systems. Specifically, a nanosuspension, nano-emulsion and silica-lipid hybrid (SLH) microparticles were formulated and the influence of composition and nanostructure on the mechanism of solubilisation was compared. Formulations were shown to enhance fasted state solubilisation levels in vitro by up to 5.9-fold, compared to pure drug. Fed- and fasted-state solubilisation profiles revealed that in contrast to the nanosuspension and nano-emulsion, lurasidone SLH mitigated the positive pharmaceutical effect of lurasidone. In vivo pharmacokinetic evaluations revealed that the nanosuspension, nano-emulsion and SLH enhanced the bioavailability of lurasidone by 3-fold, 2.4-fold and 8.8-fold, respectively, compared to pure drug after oral administration. For lurasidone, the combination of lipid-based nanostructure and porous silica nanostructure (SLH) led to optimal fasted state bioavailability which can ultimately result in enhanced treatment efficacy, easier dosing regimens and improved patient outcomes.

Clinical translation of silica nanoparticles

Silica nanoparticles have entered clinical trials for a variety of biomedical applications, including oral drug delivery, diagnostics, plasmonic resonance and photothermal ablation therapy. Preliminary results indicate the safety, efficacy and viability of silica nanoparticles under these clinical scenarios.