Formulation and evaluation of chitosan-based nanogel for oral delivery of diosmin.

The bioactive flavonoid diosmin (DSN) has a variety of biological activities, excellent therapeutic activity, however, it has a number of biopharmaceutical problems that limit its advantages. The present study aims to develop chitosan-based nanogels (NGs) as drug-delivery platforms for DSN and characterize them using physicochemical methods. DSN-loaded NGs were prepared using the ionic gelation method and particle size (PS), poly-dispersity index (PDI), zeta potential (ZP), loading efficiency (LE) and loading capacity (LC) of 113.07±12.62nm, 0.266±0.08, 22.32± 0.56 mV, 81.56±2.65% and 10.25±1.43% were obtained, respectively. Transmission electron microscopy analysis of DSN-loaded NGs also revealed that the PS ranged from 100 to 200nm, which is comparable to the outcomes of the dynamic light scattering technique. The NGs swelled in pH 6.8 and pH 7.4 buffers and was easily eroded at pH 1.2 and pH 4.5. DSN was released from NGs in acidic buffers by a Fickian process and this release was followed by both swelling and erosion. According to stability experiments, the PS, ZP and PDI at 25oC and 40oC did not significantly change after 90 days. In conclusion, the NGs system proved very effective at delivering DSN orally.