An ultra-sensitive capacitive microwire sensor for pathogen-specific serum antibody responses

Area of Science:

• Biomedical Engineering
• Immunology
• Infectious Diseases

Background:

• Serological techniques like ELISA are standard for viral infection detection via antibody response.
• ELISA assays have limitations in sensitivity and point-of-care applicability.
• Current methods struggle with rapid, sensitive detection of low antibody concentrations and isotype determination.

Purpose of the Study:

• To develop a novel, label-free biosensor for rapid detection of ultra-low concentrations of virus-specific antibodies.
• To create a sensitive and specific diagnostic tool for determining antibody isotypes.
• To evaluate the potential of a microwire sensor platform for point-of-care diagnostics.

Main Methods:

• Development of a capacitive biosensor utilizing microwires coated with Zika or Chikungunya virus envelope antigen.
• Testing the sensor's ability to detect ultra-low concentrations of virus-specific antibodies.
• Assessing the sensor's capacity for rapid and accurate antibody isotype determination.
• Validation using dilute mouse serum for anti-Zika virus antibody detection and isotyping.

Main Results:

• The microwire biosensor achieved label-free, rapid detection of virus-specific antibodies.
• The sensor demonstrated high sensitivity, detecting as few as 10 antibody molecules in 30 µL with minimal nonspecific binding.
• Accurate and rapid determination of antibody isotypes was achieved.
• Sensitive and specific detection of anti-Zika virus antibodies in mouse serum, including isotyping, was demonstrated.

Conclusions:

• The developed microwire sensor platform offers a sensitive, rapid, and specific method for detecting virus-specific antibodies.
• The platform shows significant potential as an inexpensive and reliable diagnostic tool for immune responses at the point of care.
• This novel technique overcomes limitations of traditional serological assays for viral infection diagnostics.