The study is planned to develop novel PLGA based nanoparticle delivery system of 5-Fluorouracil to treat colorectal cancer. pH
sensitive polymer, Eudragit S 100 and PLGA were used to design the dosage form to target colonic region. Emulsion droplet
coalescence method was employed to formulate nanoparticles. These nanoparticles were further characterized for their size,
morphology, zeta potential, drug entrapment, Particle Size analysis, cytotoxicity study, in vitro release study and kinetic analysis.
Formulation F2 proved to be better and showed 72.89 ± 1.41 drug entrapment with ideal particle size of 132.57nm ± 12.62. In vitro
release of F2 formulation showed a lag phase for 4 hrs (pH 1.2 and pH 6.8). Initially, there was a burst release of 17.22% at 7th hr and
further there was a controlled release up to 78.23% for 24 hrs. In vitro kinetic study indicated that the formulations followed first order
release pattern and anomalous transport kinetics, i.e. a combined mechanism of pure diffusion and Case II transport. For biological
evaluation, HT29 (Human colorectal Adenocarcinoma) cell lines were selected and anti-tumoral efficacy was analyzed using MTT (3-
[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay. Results showed that 80% of cell lysis took place. Formulation F2
was a promising formulation to target colon cancer cells.