A membrane-based immunosensor enabling high antifouling performance and sensitive molecular recognition.

Area of Science:

• Biomedical Engineering
• Biosensing Technology
• Surface Chemistry

Background:

• Non-targeted biomolecule fouling on sensing surfaces significantly degrades immunosensor performance.
• Hydrophilic polymers offer antifouling but can reduce antibody density, decreasing sensitivity.
• A balance between antifouling and high sensitivity is crucial for practical immunosensing platforms.

Purpose of the Study:

• To develop a novel porous-membrane-based immunosensor that achieves both high sensitivity and effective antifouling.
• To mitigate signal reduction caused by antifouling moieties through antibody densification within submicron pores.
• To optimize the receptor/antifouling moiety ratio using numerical modeling.

Main Methods:

• Fabrication of a porous-membrane-based immunosensor.
• Incorporation of antifouling moieties and antibody densification within submicron pores.
• Numerical modeling to determine the optimal ratio of receptor to antifouling moiety.
• Performance evaluation using interleukin-6 (IL-6) detection in artificial saliva and serum.

Main Results:

• The designed immunosensor successfully integrated antifouling properties with high sensitivity.
• Antibody densification in submicron pores effectively mitigated signal loss associated with antifouling.
• The sensor demonstrated excellent antifouling capabilities and high sensitivity for IL-6 detection.
• Achieved limits of detection of 4.8 pg mL-1 in artificial saliva and 1.2 pg mL-1 in serum.

Conclusions:

• The porous-membrane-based immunosensor effectively addresses the challenge of achieving both high sensitivity and antifouling.
• The strategy of antibody densification in submicron pores is a promising approach for enhancing immunosensor performance.
• The developed sensor shows significant potential for practical diagnostic applications, particularly in complex biological matrices.