Portable Device for Optical Quantification of Hemozoin in Diluted Blood Samples

IEEE Trans Biomed Eng. 2020 Feb;67(2):365-371. doi: 10.1109/TBME.2019.2913454. Epub 2019 Apr 26.

Abstract

Objective: This paper focuses on a novel and portable device prototype with optical detectors to quickly and efficiently detect hemozoin (Hz) in blood, aiming at malaria diagnostics.

Methods: Taking advantage of the particular features of malaria parasite in infected blood, particularly the Hz formation, the main innovation described is a portable device for the optical quantification of parasitic Hz in blood, through optical absorbance spectrophotometry. This device comprises detection chambers for fluidic samples, an optical emission and detection system, and a power supply system to provide autonomy. The working principle is based on colorimetric detection, by absorbance, at six specific wavelengths. A detection algorithm relates the absorbance values at all wavelengths to quantify the Hz concentration, thus working as a biomarker of malaria presence and stage.

Results: Under the tested conditions, e.g., in fluidic samples containing synthetic Hz, hemoglobin, and diluted whole blood, the device detected Hz above 1 μg/mL concentrations with 100% sensitivity and 96.3% specificity.

Conclusion: This paper features an autonomous, portable, 1-min analysis time, and low-cost per test device, without the need for samples, centrifugation, allowing the use of whole blood.

Significance: The presented device is a step ahead for meeting the growing clinical demands for reliable, rapid, portable, and quantitative malaria diagnosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Blood Chemical Analysis / instrumentation*
  • Equipment Design
  • Erythrocytes / chemistry
  • Hemeproteins / analysis*
  • Humans
  • Malaria / diagnosis*
  • Point-of-Care Testing
  • Spectrophotometry / instrumentation*

Substances

  • Hemeproteins
  • hemozoin