Fabrication of Biodegradable Poly(naringin) Particles with Antioxidant Activity and Low Toxicity

Naringin (NR, 4′,5,7 trihydrocyflavanone-7-O-rhamnoglucoside) is a flavanone found in citrus fruit that is composed of a phenolic compound, naringenin, and a disaccharide, neohesperidose. Poly­(NR) [p­(NR)] particles in the size range of few micrometers to few hundred nanometers were prepared from highly purified NR and subsequently characterized using UV/visible spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, scanning electron microscopy, thermogravimetric analysis, and zeta potential measurements. The hydrolytic degradation of p­(NR) particles at 37.5 °C was investigated at pHs 5.4, 7.4, and 9.0. The particles degraded most rapidly at pH 7.4, with >90% degradation after 5 h. The cytotoxicity was assessed by growing COS-1 fibroblasts for 5 days in the presence of increasing concentrations of NR or eluates from the p­(NR) particles. Both NR and p­(NR) particles were nontoxic for these mammalian fibroblasts; at the highest concentration tested (571 μg/mL), the percentages of surviving cells after 5 days in culture were 96.7 ± 0.93 and 91 ± 11% for NR and p­(NR), respectively. The effect of p­(NR) on red blood cell hemolysis was also negligible (