Fabrication and evaluation of carboxymethyl guar gum-chitosan interpenetrating polymer network (IPN) nanoparticles for controlled drug delivery

Guar gum (GG) has drawn more interest from researchers in the last several decades for the controlled delivery of drugs. The aim of the research is to fabricate and evaluate an interpenetrating polymer network (IPN) based nanocarriers system employing chemically modified GG to achieve controlled release of drug. In present study, we have reported the synthesis of carboxymethyl GG-chitosan IPN nanoparticles for controlled release of metformin hydrochloride. Carboxymethyl guar gum (CMGG) was synthesized and employed for developing IPN nanoparticles in combination with chitosan in varying polymeric ratios. A cross-linking agent, sodium tripolyphosphate (Na-TPP) was used for the synthesis of IPN colloidal suspension of nanoparticles which was lyophilized to obtain nanoparticles. The carboxymethylation of GG was confirmed through Fourier transform infra-red spectroscopy. The mean particle size was 440.6 nm indicating a polydispersity index of 0.528. The drug entrapment efficiency was found to vary between 67.46±1.64% to 88.23±2.02%. The differential scanning calorimetry study revealed the presence of amorphous metformin hydrochloride as a homogenous dispersion in nanoparticles (NPs) matrix. In vitro drug release study indicated controlled release ability of developed IPN matrix. A2 formulation (chitosan:CMGG -1:1) exhibited 78.11±0.27% release after 8 h. Antidiabetic evaluation performed in alloxan-treated diabetic rat model exhibited a prolonged hypoglycemic efficacy over 6 h, for A2 formulation treated group, compared to the group receiving only metformin HCl, which demonstrated a reduction in blood glucose levels for up to 4 h. The study findings demonstrated the efficacy of the CMGG-chitosan based IPN nanoparticulate system for sustained delivery of therapeutic agents.