A microfluidic paper-based device to assess acetylcholinesterase activity.

Area of Science:

• Biochemistry
• Analytical Chemistry
• Neuroscience

Background:

• Neurotransmitters are crucial chemical messengers facilitating cell-to-cell communication in vital biological processes.
• Acetylcholinesterase (AChE) is a key enzyme in neurotransmission, making its activity a target for research and drug development.

Purpose of the Study:

• To introduce a novel, low-cost microfluidic paper-based analytical device (μPAD) for the detection of acetylcholinesterase (AChE) activity.
• To demonstrate the utility of the μPAD for colorimetric analysis of AChE activity and for screening enzyme inhibitors.

Main Methods:

• Fabrication of the μPAD using a simple wax printing technique on chromatographic paper to create hydrophobic barriers.
• Colorimetric detection of AChE activity by spotting reagents (DTNB and AChE/ATC or Cys) onto the μPAD, allowing reactions to occur upon mixing.
• Analysis of the colorimetric output via scanning and quantification of color intensity to determine enzyme activity and inhibitor efficacy.

Main Results:

• The μPAD demonstrated a linear range for quantifying AChE activity by measuring inverse yellow intensities against substrate concentration.
• The device successfully determined an IC50 value of 0.045 nM for the inhibitor neostigmine bromide (NB).
• The developed μPAD is cost-effective and easy to fabricate, showing high potential for neurotransmitter activity quantification.

Conclusions:

• The novel μPAD provides a simple, low-cost, and effective platform for detecting AChE activity and screening inhibitors.
• This technology holds significant promise for accessible and rapid analysis of neurotransmitter-related enzyme activity in various research and diagnostic settings.
• The μPAD's ease of fabrication and use makes it a valuable tool for advancing studies in neuroscience and analytical biochemistry.