Paper-based microfluidic analytical devices have gained rapid development since their original introduction by the Whitesides Research Group a decade ago.
This class of paper-based devices, exhibiting both water-loving and water-hating characteristics, have many practical advantages including high sensitivity, accurate and rapid analysis, good biocompatibility, and low cost. They are recognized as a powerful analytical platform in various applications such as food and water analysis, chemical detection, and point-of-care diagnostics.
Challenges in making paper-based microfluidic analytical devices
Realizing a practical paper-based microfluidic analytical device, however, is still facing many challenges.
The current colorimetric and fluorescence assays usually suffer from light scattering due to the influence of environmental light conditions, resulting in poor quantitative performance.
Built-in sensors allow antibody detection
In a study presented in the scientific journal Angewandte Chemie, a group of researchers from the Eindhoven University of Technology, The Netherlands, and Keio University, Japan, developed a practical and reliable way to test for infectious diseases.
This medical technology uses only a special glowing paper strip, a drop of blood, and a digital camera. The built-in bioluminescence resonance energy transfer switches are capable of detecting various antibodies in blood samples, and at the same time, generating a colorimetric signal.
To test for the presence of infectious diseases, a photograph is simply taken 20 minutes after the blood sample is dropped on the paper devices. A biochemical reaction would cause the underside of the paper to emit blue-green light. The brighter the color, the higher the concentration of antibodies. Using this medical technology, the research team has successfully tested three antibodies simultaneously, for HIV, flu, and dengue fever.
This medical technology developed by the researchers is simple, low-cost, lightweight, and reliable. It has a lot of potential in developing countries for the easy testing of tropical diseases.
Further study should be carried out to investigate the influence of the sample volume on the antibody concentration values.
Reference: Keisuke Tenda, Benice van Gerven, Remco Arts, Yuki Hiruta, Maarten Merkx, Daniel Citterio. Paper-Based Antibody Detection Devices Using Bioluminescent BRET-Switching Sensor Proteins. Angewandte Chemie, 2018; DOI:10.1002/anie.201808070