Micro-Spectroscopy of Single Erythrocytes Infected with the Malaria Parasite

Abstract

The erythrocytic cycle of the malaria parasite Plasmodium falciparum is marked with structural, mechanical and biochemical modifications to the host red blood cell. The parasite degrades the hemoglobin of the host cell and hydrolyzes it into hemozoin. We investigate healthy and infected erythrocytes using micro-Raman and spatially resolved absorption spectroscopy. The electronic absorption spectrum of a single cell is measured and spectral changes are related to the parasite life cycle. The Soret absorption band in the trophozoite stage is shifted to higher wavelength by 3 nm. The findings are compared with micro-Raman spectra that show consistent changes in the heme vibrations. Micro-absorption may offer a potential diagnostic marker for identifying pathological states accompanying malaria.