Development and Characterization of Chitosan-Poly (Vinyl Pyrrolidone) Blend Microspheres for Controlled Release of Metformin Hydrochloride

Biguanide Pharmaceutical Formulations and the Applications of Bile Acid-Based Nano Delivery in Chronic Medical Conditions

Biguanides, particularly the widely prescribed drug metformin, have been marketed for many decades and have well-established absorption profiles. They are commonly administered via the oral route and, despite variation in oral uptake, remain commonly prescribed for diabetes mellitus, typically type 2. Studies over the last decade have focused on the design and development of advanced oral delivery dosage forms using bio nano technologies and novel drug carrier systems. Such studies have demonstrated significantly enhanced delivery and safety of biguanides using nanocapsules. Enhanced delivery and safety have widened the potential applications of biguanides not only in diabetes but also in other disorders. Hence, this review aimed to explore biguanides’ pharmacokinetics, pharmacodynamics, and pharmaceutical applications in diabetes, as well as in other disorders.

Preparation of grafting copolymer of acrylic acid onto loess surface and its adsorption behavior

Loess is a typical natural mineral particle distributed widely around the world, and it is inexpensive, readily accessible, and harmless to the environment. In this study, loess was modified by surface grafting copolymerization of functional monomers, such as acrylic acid, N-vinyl pyrrolidone, and N,N-methylenebisacrylamide as a cross-linking agent, which afforded a novel loess-based grafting copolymer (LC-PAVP). After being characterized by scanning electron microscopy, thermal gravimetric analysis and Fourier-transform infrared spectroscopy, its adsorption capacity and mechanism of removing lead ions (Pb²⁺) were investigated. With the study of the optimal experimental conditions, it was demonstrated that the removal rate of Pb²⁺ by LC-PAVP can reach up to 99.49% in 60 min at room temperature. It was also found that the kinetic characteristics of the adsorption capacity due to the pseudo-second-order kinetic model and the thermodynamics conformed well with the Freundlich model. In summary, as a lost-cost and eco-friendly loess-based adsorbent, LC-PAVP is a good potential material for wastewater treatment.