Formulation, optimization, and in-vitro-ex-vivo evaluation of dual-crosslinked zinc pectinate-neem...

Low methoxy pectin (LM pectin) suffers from burst release owing to its high swellability and solubility in water. Consequently, in ways to design an ideal drug delivery system, these obstacles must be surmounted. Therefore, the work aimed to design dual crosslinked LM pectin -neem gum (NG) mediated interpenetrating polymer network (IPN) floating mucoadhesive microbeads for lansoprazole (LNZ) gastro-retentive delivery. In short, LNZ-loaded floating microbeads were achieved by using the ionic gelation method wherein zinc acetate was preferred as a crosslinking agent. The optimization of IPN microbeads was performed employing a 3²factorial design wherein concentration of pectin and NG was considered as independent factors whereas dependant factors are entrapment efficiency and drug release. Importantly, carboxylic functionality of low methoxy (LM) pectin and hydroxylic functionality NG cross-linked with Zn⁺² forms a 3D network. Diffractogram and thermogram revealed that conversion of drug from crystalline to amorphous form because of entrapment of drug within polymeric network. Anticipated floating microbeads showed that polymer concentration had considerable effect on drug encapsulation efficiency and drug release. Briefly, optimizing floating microbeads (Batch B:5) showed maximum drug entrapment (87.47 %) with a delayed drug release (69.20 %, at 8 h) due to formation of strong IPN. Moreover, it showed good mucoadhesive aptitude with goat stomach mucosa because of entanglement between gum and mucus layer. In addition, use of calcium silicate assists to modulate floating profile of IPN microbeads. Therefore, designing dual crosslinked zinc-pectinate-NG mediated IPN floating mucoadhesive microbeads will offer a new substitute for floating delivery.