Combinable poly(dimethyl siloxane) capillary sensor array for single-step and multiple enzyme inhibitor assays

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Materials Science

Background:

• Enzyme inhibitor assays are crucial for drug discovery and diagnostics.
• Conventional capillary methods face challenges in immobilizing multiple reagents for single-step assays.
• There is a need for simplified, efficient, and versatile assay platforms.

Purpose of the Study:

• To introduce a new fabrication method for a combinable poly(dimethyl siloxane) (PDMS) capillary (CPC) sensor.
• To demonstrate the CPC sensor's utility in simplifying enzyme inhibitor assays.
• To showcase the potential for multiple and multiplexed assays using CPC arrays.

Main Methods:

• Fabrication of convex and concave PDMS sticks with differentially soluble/insoluble coatings.
• Combining PDMS sticks to form thin, long capillary structures.
• Introducing inhibitor solutions via capillary action to trigger reagent dissolution and reaction.
• Arraying multiple CPCs for multiplexed protease inhibitor assays.

Main Results:

• Successfully developed the combinable PDMS capillary (CPC) sensor.
• Simplified enzyme inhibitor assays into a single step with fluorescence response.
• Demonstrated the ability to immobilize two reactive reagents within the same capillary.
• Successfully arrayed two independent CPCs for multiplexed protease inhibitor assaying.

Conclusions:

• The CPC sensor offers a simplified, single-step approach for enzyme inhibitor assays.
• The unique "zipper-like" assembly allows easy fabrication of complex capillary structures.
• The CPC platform is versatile for both single and multiple, multiplexed diagnostic assays.