10.22376/ijpbs.2019.10.1.p1-12 Volume 15 Issue 2 April-June According to the working group of the European Science Foundation (2004), "Nanomedicine" is built on a complex systems of nanometer-scale size consisting of at least two components, one of which is an active pharmacological ingredient and the whole system leading to a special function related to the diagnosis, treatment, or prevention of disease. Nano-scale was taken to include active components or objects in the size range from 1 nm to 100 nm. The added advantages of nanoparticles over microparticles include improving drug encapsulation, pharmacokinetics, bioavailability, and therapeutic efficacy. Nanotechnology has opened up a new era in the field of drug delivery. The present study aimed to develop, evaluate, and optimize isoniazid loaded chitosan nanoparticles. Isoniazid nanoparticles were made to improve antitubercular therapy's efficacy and patient compliance by sustaining the drug release from biocompatible and biodegradable polymeric nanoparticulate formulation for up to 24 hours. The effect of various formulation variables like Isoniazid, chitosan, and the amount of gum for fenugreek seeds was investigated. The Isoniazid nanoparticles were prepared using the Ionic gelation method, and evaluation was done. Five formulations, F1 to F5, were prepared by varying the chitosan concentration. The particle size was found to be in the range of 276.5 to 597.0 nm. The particle size decreased with an increase in the concentration of chitosan. The entrapment efficiency of chitosan nanoparticles was ranged from 59.55% to 75.22%. The entrapment efficiency increased with an increase in the concentration of chitosan. The in-vitro drug release studies were carried out in phosphate buffer pH 7.4 for 24hrs. The extent of drug release was found in the range of 58.39% to 73.28%. The drug release was found to increase with the increase in the concentration of chitosan. The F3 formulation was selected as an optimized batch. The lyophilized Isoniazid nanoparticles, having particle size 276.5 nm and entrapment efficiency 75.22%, were then studied for in-vitro drug release in phosphate buffer pH 7.4. About 58.39% of the drug was observed to be released throughout 24 hrs using phosphate buffer (pH 7.4) as a dissolution medium. Sanju, S.K. Singh, Prashant Purohit, Tejaram and Kashi Ram Isoniazid, polymer, nanoparticles, tuberculosis, biodegradable 31-39