The lack of prompt and sensitive diagnosis hampers malaria control and elimination,
highlighting the need for next generation technology alternative for the established optical
microscopy and Rapid Diagnostic Tests (RDTs) as means of in situ point-of-care malaria
parasite detection. Hemozoin (Hz), a byproduct of hemoglobin (Hb) degradation inside
human infected red blood cells (RBCs), has been extensively explored as a malaria
biomarker. Along with malaria parasite maturation inside the RBC, Hb and Hz proportion
is inversely related, which originates specific optical spectra of healthy and infected
samples. Herein, we characterized the optical spectra of Plasmodium falciparum-infected
RBCs, aiming the development of an innovative diagnostic device, detecting malaria
without finger prick blood sampling, measuring directly in patients’ skin. Absorbance and
reflectance spectrophotometry demonstrate their potential by increasing the limit of
detection (LoD: 12 parasites/μL of RBC) when compared with microscopy or RDT (LoD:
50-200 parasites/μL of RBC). This sensitivity, coupled with the possible integration into
a low-cost, fast, and non-invasive diagnostic device meets the growing clinical demands
for malaria control and elimination.This work was supported by Fundação para a Ciência e Tecnologia (FCT) national funds,
under the national support to R&D units grant, through the reference project
UIDB/04436/2020 and UIDP/04436/2020. It is also supported by NORTE-01-0145-
FEDER-028178 funded by NORTE 2020 Portugal Regional Operational Program under
PORTUGAL 2020 Partnership Agreement through the European Regional Development
Fund and the FCT. V. Baptista thanks FCT for the SFRH/BD/145427/2019 grant. Maria
Isabel Veiga thanks FCT for her contract funding provided through
2020.03113.CEECIND. Susana Catarino thanks FCT for her contract funding provided
through 2020.00215.CEECIND
