Macrophage-targeted chitosan anchored PLGA nanoparticles bearing doxorubicin and amphotericin B against visceral leishmaniasis

Abstract

Novel chitosan-coated nanoparticles with a high payload of amphotericin B (AmB) and doxorubicin (Dox) were formulated employing a nanoprecipitation technique and evaluated for antileishmanial activity against Leishmania donovani. FTIR, DSC and TG-DTA analysis ensured the physicochemical compatibility of drugs and polymers. The chitosan-coated optimized nanoparticle formulation resulted in a mean particle size; 374.4 ± 4.8 nm, PDI; 0.227 ± 0.035 and zeta potential; (+) 32.9 ± 1.10 mV. The entrapment efficiency was determined to be 70.2 ± 4.76 and 93.86 ± 2.61% for AmB and Dox respectively. An in vitro drug release study demonstrated the release of 27.29 and 36.93% AmB and Dox, respectively after 24 h from chitosan-coated PLGA nanoparticles which is slower than the release obtained from uncoated PLGA nanoparticles of AmB and Dox (32.82 and 57.93% AmB and Dox respectively after 24 h). Stability studies confirmed no remarkable alterations in the physicochemical properties of nanoparticles. Cs-PLGA-ABDx was less hemotoxic (22.87 ± 0.487%) than PLGA-ABDx (36.71 ± 2.08%) and the ABDx suspension (97.04 ± 5.01%) at 42.78 μg mL⁻¹ AmB and 80 μg mL⁻¹ Dox. Cell uptake investigation showed the mean florescence intensity of chitosan-coated PLGA-FITC was 2.02 fold higher than uncoated PLGA-FITC nanoparticles. The cytotoxicity in J774A.1 cells revealed Cs-PLGA-ABDx was less cytotoxic compared to the ABDx suspension and PLGA-ABDx, whereas the IC₅₀ of Cs-PLGA-ABDx against infected macrophages was significantly (p < 0.05) lower than PLGA-ABDx indicating the effectiveness of Cs-PLGA-ABDx. No significant increase in the biomedical markers AST, BUN and PC was observed in Cs-PLGA-ABDx treated groups at 1 and 3 mg kg⁻¹ dose. These experimental findings put forward Cs-PLGA-ABDx to be a suitable alternative in the management of visceral leishmaniasis.