Development of copolymeric nanoparticles of hypocrellin B: Enhanced phototoxic effect and ocular distribution

    loading  Checking for direct PDF access through Ovid


In the present work, we have developed a photosensitizer hypocrellin B (HB) and nano silver loaded PLGA-TPGS nanoparticles with improved singlet oxygen production for enhanced photodynamic effect for the efficient treatment of age related macular degeneration. Random copolymer (PLGA-TPGS) synthesized by ring opening and bulk polymerization was characterized by IR, 1H NMR and TGA analysis. HBS-CP-NPs prepared by nanoprecipitation techniques were spherical shaped 89.6–753.6 nm size particles with negative zeta potential. The average encapsulation efficiency was 84.06 ± 11.43% and HB release from the HBS-CP-NPs was found to be biphasic with a slow release of 1.41% in the first 8 h and 48.91% during 3 days as measured by RP-HPLC. DSC thermograms indicate that HB was dispersed as amorphous form in HBS-CP-NPs. The ROS generation level of HBS-CP-NPs was significantly higher than that of HB/HB-CP-NPs. The production of 1O2 of HBS-CP-NPs has been assessed using EPR spectrometer. The 1O2 generating efficiency follows the order of nano silver > HB-CP-NPs > HBS-CP-NPs > pure HB drug solution. The superior phototoxic effect of HBS-CP-NPs (85.5% at 50 μM) was attained at 2 h irradiation in A549 cells. Significant anti angiogenic effect of HBS-CP-NPs was observed in treated CAM embryos. Following intravenous injection of HBS-CP-NPs to rabbits, the maximum amount of HB was found in retina (3 h), iris (9 h), aqueous humour (9 h) and vitreous humour (9 h).

Related Topics

    loading  Loading Related Articles