Raman and resonance Raman spectroscopic study of red blood cells in patients diagnosed with malaria

Abstract

Raman spectroscopy was used to study erythrocytes collected from patients diagnosed with malaria at the University Hospital in Kraków and from healthy volunteers. A laser line with a wavelength of 442 nm was used to induce the Raman resonance of haem, while a laser with a wavelength of 785 nm was used for the normal Raman effect. The results were analysed using Principal Component Analysis. For the 442 nm laser line, analysis of the entire spectral range (3200 cm⁻¹ to 300 cm⁻¹) showed satisfactory separation of Raman spectra for healthy cells from infected cells, which was significantly improved in the 1500 cm⁻¹–1200 cm⁻¹ spectral range. For the 785 nm laser line, some separation was observed in each range studied, but the best results were achieved over the full spectral range. Plasmodium-derived nucleic acids and phosphodiester vibrations were observed at excitation lines of 442 nm and 785 nm, respectively.