Enhancing the sensing specificity of a MoS₂ nanosheet-based FRET aptasensor using a surface blocking strategy

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Analytical Chemistry

Background:

• Aptamer-based biosensors offer advantages over antibody-based methods due to aptamer stability and ease of synthesis.
• Current aptasensor development requires further investigation into factors influencing performance, particularly specificity.
• Malarial diagnosis relies on detecting biomarkers like Plasmodium lactate dehydrogenase (pLDH).

Purpose of the Study:

• To enhance the sensing specificity of a fluorescence resonance energy transfer (FRET)-based MoS2 nanosheet aptasensor for pLDH detection.
• To address non-specific binding issues that reduce aptasensor accuracy.
• To improve the potential for developing robust point-of-care malaria diagnostics.

Main Methods:

• Development of a FRET-based MoS2 nanosheet aptasensor for pLDH detection.
• Investigation of non-specific protein adsorption affecting sensor performance.
• Application of a surface blocking agent (surface passivation) to mitigate non-specific binding.

Main Results:

• Non-target proteins caused significant fluorescence increase, indicating non-specific binding.
• Surface passivation effectively reduced non-specific adsorption of proteins onto the MoS2 nanosheets.
• Enhanced specificity of the aptasensor for pLDH was demonstrated after surface passivation.

Conclusions:

• Surface passivation is a key strategy to improve the specificity of MoS2 nanosheet-based aptasensors.
• The developed method contributes to more accurate and reliable point-of-care malaria diagnostics.
• Further research into aptasensor optimization can lead to advanced diagnostic tools.