Preliminary characterization of N-trimethylchitosan as a nanocarrier for malaria vaccine

Abstract

Background & objectives: With the current snags from the use of Artemisinin-combination therapies (ACTs) inmalaria treatment in addition to fear of cross-resistance to unrelated drugs, raising the immunocompetence ofindividuals in malaria endemic areas by vaccination is the best approach to malaria-free world.Methods: Water-soluble cationic derivative, N, N, N-trimethylchitosan (TMC) was synthesized from chitosan.Nanoparticles of the TMC were prepared in various media [milliQ water, Na2CO3 (pH 10.92), Na2HPO4 (PBS,pH 9.01 and alhydrogel®] which were characterized as adjuvants for possible vaccine delivery. The nanoparticleswere characterized for particle size, surface charge and morphology using microscopy (Phase contrast microscopeand Confocal laser scanning microscope), and Malvern zetasizer Nano-ZS. Time-resolved particle size analysiswas performed after one month storage of the TMC nanoparticles at 4°C.Results: The result of the study showed that PBS was the best medium that produced cationic, monodispersedand stable TMC nanoparticles of <65 nm forming a compatibly homogeneous system even upon storage. Detailsof the polyelectrolyte-doped nanoparticles in PBS showed clear coatings due to Sodium poly (styrene sulfonate)[PSS, MW ~70 kDa] at the periphery of the particles and a fluorescent core with some tiny central hollowcavities implying that the nanoparticles can either entrap the vaccine candidate into the hollow cavities oradsorb them unto the surface of the peripheral polyelectrolyte coatings.Interpretation & conclusion: This preliminary study established that TMC has the desired qualities for theintending antigen delivery. Further research regarding the biological activity of this TMC is indicated.

Keywords

• Alhydrogel
• malaria
• N-trimethylchitosan
• PBS
• nanocarrier
• vaccine