Vitamin B12-PEG4000 functionalized cellulose nanofibers for Amphotericin B delivery: In vitro evaluation for leishmaniasis treatment.

Leishmaniasis is a globally neglected infectious disease caused by protozoan parasites, and its treatment is often limited by several side effects. Amphotericin B (AmB) is highly effective anti-leishmanial drugs; however, its oral administration is restricted due to low bioavailability and toxicity. To overcome these limitations, a novel formulation (VitB12-PEG4000-AmB-CNFs) was developed for delivery of AmB using Vitamin B12-PEG4000 conjugate and functionalized cellulose nanofibers. The optimized formulation exhibits a particle size of 490 nm with a positive surface charge (+28.53 mv), and a high BET surface area (42.08 m2/g), supporting efficient drug loading. FTIR, XRD, SEM-EDS confirmed the functionalization, drug encapsulation, and conjugate binding. In vitro assays demonstrate prolonged drug release, mucoadhesive properties and gastrointestinal stability. VitB12-PEG4000-AmB-CNFs showed strong anti-leishmanial activity against Leishmania donovani intramacrophage amastigotes while minimizing cytotoxicity to host cells. This formulation offer promising oral nanocarrier system, combining targeted delivery with reduced toxicity, to address persistent challenges in leishmaniasis treatment.