Probing the effect of various lipids and polymer blends on clopidogrel encapsulated floating microcarriers

Gastroretentive drug delivery systems: A holy grail in oral delivery

Gastroretentive drug delivery systems (GRDDSs) offer a promising strategy for enhancing oral drug bioavailability by prolonging gastric residence time and enabling site-specific drug release. This review examines the key materials used in GRDDSs, including polymers for controlled drug release, gas-generating agents for buoyancy, and mucoadhesive components for improved retention and stability. Advances in fabrication techniques, such as 3D printing, spray drying, and nanoparticle encapsulation, have enabled precise modulation of drug release kinetics and retention properties. However, challenges such as inter-subject variability, physiological constraints, and manufacturing scalability remain. Future research will focus on smart materials, multi-drug platforms, and expanding applications to biologics and nutraceuticals, paving the way for more effective and patient-compliant oral drug delivery systems.

Development of Lipid-Based Gastroretentive Delivery System for Gentian Extract by Double Emulsion-Melt Dispersion Technique

Gentian (Gentiana lutea L., Gentianaceae) root extract (GRE) is used for the treatment of gastrointestinal disorders. However, its bioactive potential is limited in conventional forms due to the low bioavailability and short elimination half-life of the dominant bioactive compound, gentiopicroside. The aim of study was to encapsulate GRE in the lipid-based gastroretentive delivery system that could provide high yield and encapsulation efficiency, as well as the biphasic release of gentiopicroside from the tablets obtained by direct compression. Solid lipid microparticles (SLM) loaded with GRE were prepared by freeze-drying double (W/O/W) emulsions, which were obtained by a multiple emulsion-melt dispersion technique, with GRE as the inner water phase, Gelucire^® 39/01 or 43/01, as lipid components, with or without the addition of porous silica (Sylysia^® 350) in the outer water phase. Formulated SLM powders were examined by SEM and mercury intrusion porosimetry, as well as by determination of yield, encapsulation efficiency, and flow properties. Furthermore, in vitro dissolution of gentiopicroside, the size of the dispersed systems, mechanical properties, and mucoadhesion of tablets obtained by direct compression were investigated. The results have revealed that SLM with the macroporous structure were formulated, and, consequently, the powders floated immediately in the acidic medium. Formulation with porous silica (Sylysia^® 350) and Gelucire^® 43/01 as a solid lipid was characterized with the high yield end encapsulation efficiency. Furthermore, the mucoadhesive properties of tablets obtained by direct compression of that formulation, as well as the biphasic release of gentiopicroside, presence of nanoassociates in dissolution medium, and optimal mechanical properties indicated that a promising lipid-based gastroretentive system for GRE was developed.

Responsive Hydrogel Microcarrier-Integrated Microneedles for Versatile and Controllable Drug Delivery

Stratagems of drug delivery are important for disease treatment and other biomedical areas. In this study, a novel stratagem is presented for versatile and controllable drug delivery by integrating photoresponsive drug delivery microspheres (PDDMs) into pyramid microneedle (MN) arrays. The PDDMs, containing black-phosphorus (BP) and poly (N-isopropylacrylamide) (pNIPAM), are generated by a flexible capillary microfluidic method. Benefiting from the high water content of the pNIPAM hydrogel, various bioactive substances can be loaded and maintain biological activity. Furthermore, due to the near-infrared (NIR) absorption and conversion capabilities of the contained BP, the PDDMs can increase temperature, shrink volume, and release their encapsulated bioactives under the trigger of biocompatible NIR. In addition, as the PDDMs are stuffed into the solid MN arrays of porous ethoxylated trimethylolpropane triacrylate (ETPTA), the composited PDDMs-MNs system has enough mechanical strength to penetrate into the skin and can deliver drugs underneath the skin uniformly. Based on the resultant PDDMs-MNs, it is demonstrated that insulin can be controllably released to adjust blood glucose levels of streptozotocin (STZ)-induced diabetic mice. Thus, it is believed that the PDDMs-MNs can act as an excellent drugs delivery system and will find many practical values in clinical medicine.

Expedition of Eudragit® Polymers in the Development of Novel Drug Delivery Systems

Eudragit® polymer has been widely used in film-coating for enhancing the quality of products over other materials (e.g., shellac or sugar). Eudragit® polymers are obtained synthetically from the esters of acrylic and methacrylic acid. For the last few years, they have shown immense potential in the formulations of conventional, pH-triggered, and novel drug delivery systems for incorporating a vast range of therapeutics including proteins, vitamins, hormones, vaccines, and genes. Different grades of Eudragit® have been used for designing and delivery of therapeutics at a specific site via the oral route, for instance, in stomach-specific delivery, intestinal delivery, colon-specific delivery, mucosal delivery. Further, these polymers have also shown their great aptitude in topical and ophthalmic delivery. Moreover, available literature evidences the promises of distinct Eudragit® polymers for efficient targeting of incorporated drugs to the site of interest. This review summarizes some potential researches that are being conducted by eminent scientists utilizing the distinct grades of Eudragit® polymers for efficient delivery of therapeutics at various sites of interest.