FORMULATION AND IN VITRO & IN VIVO EVALUATION OF RISPERIDONE-LOADED BIODEGRADABLE PLGA NANOPARTICLES FOR ENHANCED BRAIN TARGETING

Ms. Priti Deshmukh* and Dr. Abhay Dharamsi

ABSTRACT

Delivering drugs across the BBB is one of the promising applications of nanotechnology in clinical neuroscience. Nanoparticles could potentially carry out multiple tasks in a predefined sequence, which is very important in the delivery of drugs across the Blood-Brain Barrier. PLGA nanoparticles were prepared by using the Solvent Displacement Method or Nanoprecipitation Technique and by using different concentrations of drug to excipient ratio, PLGA [75:25], Poloxamer-188, Acetone, water, and manufacturing attributes. The nanoparticle formulations were characterized for particle size, polydispersity index (PDI), Zeta-potential, Entrapment efficiency, DSC, XRD, and SEM studies. Optimization was performed by varying parameters like an organic solvent, drug to polymer ratio, types of surfactant, and concentration of surfactant was taken into consideration. The particle size of optimized batches was found in the range of 131 to 133 nm, with the entrapment efficiency found in the range of 88.28 to 89.87%. Entrapment efficiency was carried out by using the Sephadex G-25 column. In vitro, drug release studies of Risperidone from nanoparticles were determined using the Dialysis bag diffusion technique at a regular interval throughout 72hrs. The in-vivo drug distribution studies were performed by Gamma Scintigraphy. Balb/c mice were injected with the 99mTc-labelled complex of Risperidone-loaded nanoparticles measured for radioactivity in the brain and also in different organs by a Gamma-ray spectrometer. Risperidone in the brain was relatively 3-fold higher than plain Risperidone solution in 1 hr, followed by 3.2- fold in 4 hrs and 4.91- fold higher after 12 hrs.

Keywords: Risperidone, PLGA Nanoparticles, Poloxamer-188, Nanoprecipitation Technique, Gamma Scintigraphy, Gamma-ray spectrometer.