Mesoporous silica nanoparticles (MSNs) have advanced to the forefront of multifunctional nanoparticulate systems in nanomedicine, owing to this highly fexible materials platform enabling a multitude of design options, often in a modular fashion. Drug delivery ability, detectability via diferent imaging modalities, and stimuliresponsiveness are often combined into one particle system. Very sophisticated and versatile designs along with impressive demonstrations of applicability have been reported to date, but a common ground when it comes to some critical considerations valid for any nanoparticle intended for biomedical purposes is lacking to some degree. In this study, we attempt to take a glance at some of the most crucial aspects of biomedical nanoparticulate design and relate how they apply specifically toMSNs. These considerations include fuorophore labeling and leaching with respect to immobilization to MSNs, the surrounding conditions, carrier biodegradability, and surface coating. Surface modifcation strategies and surface charge tuning are further considered in conjunction to the relative amount of cellular uptake and serum protein adsorption. Cellular internalization routes and biological techniques used to evaluate especially in vitro biobehavior are discussed. Our attempt is hereby to draw attention to some of the most frequently occurring issues to be considered in the design of MSN systems for biomedical applications

A self-microemulsifying drug delivery system (SMEDDS) has been developed to enhance diffusion rate and oral bioavailability of valsartan. The solubility of valsartan was checked in different oils, surfactants, and cosurfactants and ternary phase diagrams were constructed to evaluate the microemulsion domain. The valsartan SMEDDS was prepared using Capmul MCM (oil), Tween 80 (surfactant), and polyethylene glycol 400 (cosurfactant). The particle size distribution, zeta potential, and polydispersity index were determined and were found to be 12.3 nm, -0.746, and 0.138, respectively. Diffusion rate of valsartan was measured by in vitro dialysis bag method using phosphate buffer pH 6.8 as diffusion media. Developed high-performance liquid chromatography method was used to determine drug content in diffusion media. Oral bioavailability of valsartan SMEDDS was checked by using rabbit model. Results of diffusion rate and oral bioavailability of valsartan SMEDDS were compared with those of pure drug solution and of marketed formulation. Diffusion of valsartan SMEDDS showed maximum drug release when compared to pure drug solution and marketed formulation. The area under curve and time showed significant improvement as the values obtained were 607 ng h/mL and 1 h for SMEDDS in comparison to 445.36 and 1.36 h for market formulation suggesting significant increase (p < 0.01) in oral bioavailability of valsartan SMEDDS.

Thus, it can be concluded that NS formulation of EFV can provide improved oral bioavailability due to enhanced solubility, dissolution velocity, permeability and hence absorption.

A multifaceted therapeutic platform has been proposed for controlled delivery of Etoposide (ETS) leading to a synergistic advantage of maximum therapeutic efficacy and diminished toxicity. A state of the art pH responsive nanoparticles (NPs) MSNs-PAA consisting of mesoporous silica nanoparticles core and polymeric shell layers, were developed for controlled release of model anti-cancer drug ETS. Graft onto strategy was employed and amination served as an interim step, laying a vital foundation for functionalization of the MSN core with hydrophilic and pH responsive polyacrylic acid (PAA). MCM-41-PAA were investigated as carriers for loading and regulated release of ETS at different pH for the first time. The PAA-MSNs contained 20.19% grafted PAA as exhibited by thermogravimetric analysis (TGA), which enormously improved the solubility of ETS in aqueous media. The synthesized PAA-MSNs were characterized by various techniques viz, SEM-EDS, TEM, BET, FT-IR and powder XRD. ETS was effectively loaded into the channels of PAA-MSN via electrostatic interactions. The cumulative release was much rapid at extracellular tumor (6.8) and endosomal pH (5.5) than that of blood pH (7.4). Hemolysis study was done for the prepared NPs. MTT assay results showed that the drug-loaded ETS-MCM-41-PAA NPs were more cytotoxic to both prostate cancer cells namely PC-3 and LNCaP than free ETS, which was attributed to their slow and sustained release behavior. The above results confirmed that PAA-MSN hold a great potential as pH responsive carriers with promising future in the field of cancer therapy.

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