Background: Intranasal administration of biodegradable nanoparticles has been extensively studied for targeting the drug
directly to CNS through olfactory or trigeminal route bypassing blood brain barrier.
Objective: The objective of the present study was to optimize Clonazepam loaded PLGA nanoparticles (CLO-PNPs) by investigating
the effect of process variables on the responses using 32
full factorial design.
Methods: Effect of two independent factors-amount of PLGA and concentration of Poloxamer 188, were studied at low, medium and
high levels on three dependent responses-%Entrapment efficiency, Particle size (nm) and %cumulative drug release at 24hr.
Results: %EE, Particle size and %CDR at 24hr of optimized batch was 63.7%, 165.1 nm and 86.96% respectively. Nanoparticles
were radiolabeled with 99mTc and biodistribution was investigated in BALB/c mice after intranasal & intravenous administrations.
Significantly higher brain/blood uptake ratios and AUC values in brain following intranasal administration of CLO-PNPs indicated
more effective brain targeting of CLO. Higher brain uptake of intranasal CLO-PNPs was confirmed by rabbit brain scintigraphy imaging. Histopathological study performed on goat nasal mucosa revealed no adverse response of nanoparticles. TEM image exhibited
spherical shaped particles in nano range. DSC and XRD studies suggested Clonazepam encapsulation within PLGA matrix. The onset
of occurrence of PTZ-induced seizures in rats was significantly delayed by intranasal nanoparticles as compared to intranasal & intravenous CLO-SOL.
Conclusion: This investigation exhibits rapid rate and higher extent of CLO transport in brain with intranasal CLO-PNPs suggesting
a better option as compared to oral & parenteral route in management of acute status epilepticus.