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The development of point-of-care, cost-effective, and easy-to-use assays for the accurate counting of CD4+ T cells remains an important focus for HIV-1 disease management. The CD4+ T cell count provides an indication regarding the overall success of HIV-1 treatments. The CD4+ T count information is equally important for both resource-constrained regions and areas with extensive resources. Hospitals and other allied facilities may be overwhelmed by epidemics or other disasters. An assay for a physician’s office or other home-based setting is becoming increasingly popular. We have developed a technology for the rapid quantification of CD4+ T cells. A double antibody selection process, utilizing anti-CD4 and anti-CD3 antibodies, is tested and provides a high specificity. The assay utilizes a microfluidic chip coated with the anti-CD3 antibody, having an improved antibody avidity. As a result of enhanced binding, a higher flow rate can be applied that enables an improved channel washing to reduce non-specific bindings. A wide-field optical imaging system is also developed that provides the rapid quantification of cells. The designed optical setup is portable and low-cost. An ImageJ-based program is developed for the automatic counting of CD4+ T cells. We have successfully isolated and counted CD4+ T cells with high specificity and efficiency greater than 90%.
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ELISA Assay with PDMS Microfluidic Channels Fabricated by 3D Printed Master Mold
Following the emergence of the SARS-CoV-2 (Covid-19) pandemic, interest in understanding antibody diagnostic testing has increased. We describe a quick and inexpensive technique that enabled students to print their own microfluidic devices that can be used to house an immunoassay for detecting a Human Immunodeficiency Virus (HIV) antibody. Both qualitative diagnostic assays and quantitative binding assays were carried out to characterize the HIV interaction with a target antibody. By performing these hands-on low-cost experiments in the analytical chemistry lab course, students were exposed to 3D fabrication, microfluidic technology, surface chemistry, protein-ligand binding affinity studies, and immunoassays within the time frame of two four–hour laboratory periods.
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- PAR ID:
- 10489401
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- The Chemical educator
- ISSN:
- 1430-4171
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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