Exploring Hibiscus rosa-sinensis Mucilage as a Natural Excipient for Sustained Metformin Release

Diabetes mellitus affects millions of people around the globe. It occurs when the pancreas does not produce enough insulin or the cells in the body become resistant to the insulin produced. The result is elevated levels of glucose in the bloodstream (hyperglycemia). Untreated diabetes mellitus leads to serious complications such as cardiovascular disease, stroke, kidney failure, eye disease, neuropathy and amputation. Sustained-release drug delivery systems provide many benefits to patients, including: consistent therapeutic plasma levels, fewer doses per day, and increased compliance with medication regimens. Polymers derived from natural sources are becoming increasingly popular in sustained-release formulations because they have low toxicity, biocompatibility, and biodegradability, making them suitable for drug delivery. One example of a natural polymer is the mucilage (gum) from Hibiscus rosa-sinensis ( H . rosa-sinensis ). The mucilage has excellent swelling properties, can form a gel matrix, maintain its structural integrity and be compatible with synthetic drug delivery systems. The mucilage is easily extracted from the plant using environmentally friendly techniques, and results in a stable polymer that is hydrophilic and has a pH-tolerant capacity, making it suitable for developing controlled drug delivery systems. Drug delivery systems formed from H. rosa-sinensis will release drugs via diffusion and/or erosion, following zero-order or higuchi kinetics. Metformin was chosen as a model drug; however, the polymer has broader application potential. Studies are needed to establish standardization, develop microbial stability, and validate clinical efficacy through additional systematic studies.