A sensitive and real-time assay of trypsin by using molecular imprinting-based capacitive biosensor

Area of Science:

• Biosensing
• Biotechnology
• Analytical Chemistry

Background:

• Trypsin is a crucial enzyme in biological processes.
• Accurate and rapid detection of trypsin is vital for various applications.
• Existing methods for trypsin detection can be time-consuming or lack sensitivity.

Purpose of the Study:

• To develop a highly sensitive and selective capacitive biosensor for label-free, real-time trypsin detection.
• To evaluate the sensor's performance, including detection limit, selectivity, and stability.
• To compare the biosensor's results with a conventional spectrophotometric method.

Main Methods:

• Utilized microcontact imprinting to create trypsin-imprinted (trypsin-MIP) capacitive electrodes.
• Performed real-time detection of trypsin in standard solutions within a wide concentration range.
• Assessed selectivity using competing proteins and evaluated sensor stability over time.
• Measured trypsin activity using a spectrophotometer with BAPNA substrate for comparison.

Main Results:

• Achieved a low detection limit of 3.0×10(-13)M for trypsin.
• Demonstrated high selectivity for trypsin over other proteins, with selectivity coefficients up to ~705.1.
• The biosensor maintained binding properties over ~80 assays during 2 months with minimal signal decrease (2.3%).
• Results from the capacitive system showed good correlation with spectrophotometric measurements (7.9mU/mL vs. 9mU/mL).

Conclusions:

• The developed capacitive biosensor offers a sensitive, rapid, and cost-effective alternative for trypsin detection.
• The label-free, real-time monitoring capability makes it suitable for various applications.
• This technology holds potential for monitoring enzymatic activity of different proteases.