in vitro antimalarial activity of chloroquine-crocus sativus conjugated to chitosan nanocomposits against 3d7 and k1 strains of plasmodium falciparum

Background: the use of nanocarriers in combination with other treatments shows significant promise in addressing drug-resistant diseases, particularly malaria. given the high prevalence of drug-resistant malaria, research into innovative therapies is crucial. this study focuses on a nanoform of chitosan, a biodegradable polymer, combined with crocus sativus (saffron) and chloroquine to enhance their antimalarial effects.methods: saffron extract and chloroquine were separately conjugated with chitosan, followed by confirmation tests to determine conjugation efficiency. both chloroquine-resistant and sensitive strains of plasmodium falciparum were cultured to calculate the ic50 values of various treatments in vitro. this study was conducted at the school of public health, tehran university of medical sciences, tehran, iran in 2024.results: confirmation tests (ftir, dls, zeta potential, tem) verified proper drug conjugation to nanocomposites, with observed nanosize, the percentage of conjugation was 64.4% for chloroquine and 42.9% for saffron. toxicity and hemolysis tests confirmed safe doses. the ic50s values for chloroquine, nanoparticle-chloroquine, saffron, and nanoparticle-saffron were 0.3, 0.8, 42.5, and 6.24 µg/ml, respectively, for the sensitive strain, and 5, 1, 12.5, and 3.12 µg/ml, respectively, for the resistant strain. combination therapy with the fixed ratio method showed synergistic effects. statistical analysis revealed synthesized nanocomposites' superior inhibition of p. falciparum growth compared to non-nano. significant differences were observed in some cases (p< 0.05).conclusion: utilizing nanocarriers and combination therapy is an appropriate strategy for addressing drug resistance. saffron's anti-malarial effects on p. falciparum were notably increased when linked to chitosan nanocomposites. furthermore, employing a fixed ratio technique enhanced the therapeutic effectiveness of saffron when combined with chloroquine and chloroquine-nanocomposites across all concentrations.