Characterization and optimization of colon targeted S-adenosyl-L-methionine loaded chitosan nanoparticles

Abstract

S-adenosyl-L-methionine (SAMe) is an endogenic methyl donor naturally present in all living cells; it hashigh water solubility, but its bioavailability is low in oral administration due to the first pass effect in the liver. The aimof this study is to prepare colon targeted chitosan nanoparticles containing SAMe by ionic gelation. In the preparationof the formulations, the effects of chitosan concentration, tripolyphosphate (TPP) concentration and the amount ofSAMe on the specifications of the nanoparticles such as particle size, zeta potential, encapsulation efficiency, andprocess yield, were investigated. Drug-excipient interactions were evaluated by differential scanning calorimetry (DSC)and Fourier transform infrared (FTIR) spectroscopy. The obtained nanoparticles showed bimodal particle sizedistribution ranging between 228.3-763.9 nm and their zeta potentials were within 14.10-23.30 mV. The drugencapsulation efficiencies and process yields of the nanoparticles were low. However, when the effects of the processparameters on the characteristics of nanoparticles were examined, the chitosan concentration and SAMe amount weresignificant parameters affecting particle size. The chitosan concentration was also found to have a significant effect onprocess yield (p