Super-hydrophobic Surfaces for Liquid Agglutination Assay

Rapid and economical detection of biomarkers and infectious agents present in biological fluids is vitally important for decision making in health care. In particular, diagnostic immunoassays based on antibody recognition have been established as very specific and powerful for a wide range of disease detection and biomarker applications.

 

Currently, antibody based in vitro diagnostics technologies (IVDT) range from simple lateral flow immunoassays to instrument-intensive systems such as enzyme-linked immunosorbent assays (ELISA). Though inexpensive and relatively portable, lateral flow assays lack sensitivity and can be misinterpreted by human readers. On the other hand, complex instrumentation for reading microtiter plate assays have greater sensitivity, quantification, and specificity, but pose challenges in miniaturization, material choice, and operability.

 

Researchers at Arizona State University have developed a novel detection method for identifying infectious disease markers directly in liquid biological samples. In this method, the biological sample is first mixed with a binding substance specific to the analyte. To prepare the sample for analysis, a drop of this mixture is then deposited on a super-hydrophobic surface. The liquid sample is exposed to an electro-magnetic radiation source, and its optical properties are measured using a photodiode detector. A large number of binding events causes agglutination in the liquid sample and changes forward light scattering. This enables a rapid test readout without generation of large amounts of liquid biohazardous waste or extensive manipulation of the original sample.

 

Potential Applications

 

Benefits and Advantages