A portable microfluidic Aptamer-Tethered Enzyme Capture (APTEC) biosensor for malaria diagnosis

Area of Science:

• Biotechnology
• Medical Diagnostics
• Parasitology

Background:

• Malaria diagnosis requires improved, accessible tools, especially in endemic regions.
• Previous work developed a DNA aptamer for sensitive and specific detection of Plasmodium falciparum lactate dehydrogenase (PfLDH).
• Existing laboratory-based assays lack portability for point-of-care use.

Purpose of the Study:

• To develop a portable, equipment-free, point-of-care biosensor for malaria diagnosis.
• To utilize aptamer-functionalized magnetic microbeads for magnet-guided detection of PfLDH.
• To optimize a microfluidic system for sensitive and specific malaria biomarker detection.

Main Methods:

• Coating magnetic microbeads with DNA aptamers targeting PfLDH.
• Designing a multi-chamber microfluidic device for magnet-guided capture, washing, and colorimetric detection.
• Optimizing microfluidic prototypes to minimize diffusion and enhance sensitivity.
• Testing the biosensor with in vitro cultured Plasmodium falciparum and clinical samples.

Main Results:

• The developed biosensor demonstrated high sensitivity and specificity in detecting PfLDH.
• Optimization of microfluidic chambers reduced inter-chamber diffusion and improved detection limits.
• The magnet-guided, equipment-free approach proved effective for point-of-care sample testing.
• Successful detection of PfLDH in both laboratory and clinical malaria samples.

Conclusions:

• A novel, portable, and equipment-free malaria biosensor concept was successfully demonstrated.
• The aptamer-mediated, magnet-guided microfluidic system offers a promising approach for point-of-care malaria diagnostics.
• This technology provides a proof-of-principle adaptable for various aptamer-based diagnostic applications.