Recent advancements in xanthan gum-based gastroretentive floating formulations: Chemical modification, production and applications

Non-toxic, biocompatible, biodegradable, and bioadhesive, characteristics, of natural polysaccharides, are widely recognized and well accepted. Their usage in dietary, medicinal, biomedical, and cosmetic, applications is due to their unique and fascinating attributes. Xanthan gum, a microbial polysaccharide possesses diverse-wonderful features. It is a naturally occurring heteropolysaccharide, with large molecular weight, derived from the Gram-negative bacteria, Xanthomonas Campestris. This biopolymer has been studied extensively as a matrix for tablets, nanoparticles, microparticles, hydrogels, and various other formulation types. However, indigenous xanthan gum has its own set of restrictions, which may be overcome by chemical modification, to fine-tune the characteristics of the native gum, for attaining unmet demands. This approach has huge potential in the drug delivery and numerous other promising applications. The objective of this review is to provide a consolidated source of information on xanthan gum-based gastroretentive systems. Several approaches of floating techniques, with recent research avenues and patents, utilizing the natural polysaccharide xanthan gum is also discussed.

Gastro retentive floating drug delivery system of levofloxacin based on Aloe vera hydrogel: In vitro and in vivo assays

Gastro retentive drug delivery systems (GRDDS) have gained immense popularity as they reduce dosing frequency, improve bioavailability, and enhance patient compliance. Herein, a plant-based, controlled swelling, and pH-sensitive GRDDS based on Aloe vera hydrogel and cellulose was developed for the sustained release of levofloxacin (LEVO). The properties of five various floating tablet formulations including dynamic swelling, pH-responsiveness, hardness, friability, drug release, and buoyant time were evaluated. The optimized formulation (FF) was characterized using FTIR and SEM, and the surface morphology exhibited a porous texture with microchannels that facilitated tablet swelling and prolonged release of LEVO. The formulation FF remained buoyant (> 12 h) in the simulated gastric fluid with a buoyancy time of 303 s. A pH-dependent swelling behavior of the formulation FF was revealed with the highest swelling (7.1 g/g) in water, followed by buffers of pH 6.8 (5.4 g/g), 4.5 (3.8 g/g), and 1.2 (2 g/g). The controlled release of LEVO was demonstrated for >12 h following the Hixson-Crowell model and non-Fickian diffusion. Pharmacokinetic parameters of LEVO were determined using in vivo studies. The non-toxic nature of the formulation under study was demonstrated. The results render this approach promising in reducing the dosing frequency, suggesting its potential for clinical applications.

Cephradine drug release using electrospun chitosan nanofibers incorporated with halloysite nanoclay

The chitosan/polyvinyl alcohol/halloysite nanoclay (CS/PVA/HNC) loaded with cephradine drug electrospun nanofibers (NFs) were fabricated and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) techniques. FTIR analysis confirmed the hydrogen bonding between the polymer chain and the developed siloxane linkages. SEM analysis revealed the formation of uniform NFs having beads free and smooth surface with an average diameter in 50–200 nm range. The thermal stability of the NFs was increased by increasing the HNC concentration. The antimicrobial activity was examined against Escherichia  coli and staphylococcus strains and the NFs revealed auspicious antimicrobial potential. The drug release was studied at pH 7.4 (in PBS) at 37 °C. The drug release analysis showed that 90% of the drug was released from NFs in 2 h and 40 min. Hence, the prepared NFs could be used as a potential drug carrier and release in a control manner for biomedical application.