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2015 People's Choice

Status of Main Author

Undergraduate Student




Cheng, Xuanhong

Publication Date



Once a patient is diagnosed as HIV-positive, tests of viral load (the concentration of virus circulating in the blood) are performed routinely in order to monitor disease progression and ensure treatment effectiveness. Currently, there is no procedure to measure viral load in a point-of-care setting. It often takes upwards of two weeks to receive a patient’s viral load results from central facilities, making it difficult for doctors to make treatment decisions or adjust medication in the case of drug resistance. Microfluidic technology offers the ability to analyze small sample volumes, encouraging the development of point-of-care systems for viral diagnostics. A microfluidic viral load analyzer needs to separate the HIV virions from plasma and quantify the targets. The small size of virions limits the use of traditional, flat-bed, immunoaffinity microfluidic devices. Thus, here we validate the effectiveness of a nanoporous filtration matrix to isolate pseudo HIV virions from a solution [1]. Adapting the methods of da la Escosura and Muniz, virions are tagged with gold nanoparticles, and the virion-gold complexes are augmented with silver deposition, increasing the volume that the complexes occupy within the capture membrane [2]. These aggregates block flow of an ionic solution through the membrane pores. The reduction of ion flow as viral capture increases can be quantified through cyclic voltammetric analysis. Initial experiments show a correlation between a decrease in peak current and an increase in simulated viral load (n=4, R2=0.934). This system, once optimized, has the potential to perform viral load quantification in a point-of-care setting. 1. Surawathanawises, Krissada. “Polymeric Nanoporous Structures Integrated into Microfluidic Device for HIV Detection,” PhD Dissertation, Lehigh University, Bethlehem, PA, 2014. 2. de la Escosura-Muniz, A.; Merkoci, A. “A Nanochannel/Nanoparticle-Based Filtering and Sensing Platform for Direct Detection of a Cancer Biomarker in Blood,” Small, 2011.

Author Notes

Jay is currently a senior studying bioengineering in the cell and tissue track, at Lehigh University. Jay began conducting research in Professor Cheng’s lab in the fall of 2011, studying cancer cell chemotaxis within an artificially created fibronectin gradient. During his Junior year, Jay began researching the concentrating effects of thermophoresis and convection within microfluidic channels, as a way of concentrating viral particles in solution. The work lead to the formation of a team between himself and Kathryn Kundrod, which set out to develop a method of analysis for microfluidic HIV capture membranes Kathryn had been researching. Upon graduation in the summer of 2015 Jay will be joining Catalent Pharmaceuticals as part of their GOLD leadership program. As well as his involvement in research at Lehigh, Jay is a member of the club ice hockey and cycling teams, and is an alumnus of the Chi Phi Fraternity.

Kathryn, is a senior at Lehigh University pursuing a B.S. in Bioengineering with a minor in Health, Medicine, and Society. She has been working to develop a point-of-care HIV viral load diagnostic device in Professor Xuanhong Cheng’s laboratory for three years with the guidance of graduate student Krissada (Chai) Surawathanawises. In addition to her research experiences at Lehigh, Kathryn interned at the National Institutes of Health, where she researched the reliability of a brain-imaging modality within a study that aims to improve rehabilitation techniques for children with cerebral palsy. Kathryn volunteers as a patient navigator at the HEARTS Clinic in South Bethlehem. There she maintains relationships with patients, who are primarily people who have faced many barriers to healthcare including the inability to obtain insurance. Her role is to connect these patients to as many community health programs as possible. Kathryn is also a part of the Martindale Student Associates program, through which she analyzed the public health effects of drug policy in Portugal. Additionally, Kathryn is involved with the Rossin Junior Fellows engineering mentorship group and Tau Beta Pi engineering honors fraternity at Lehigh. With a strong interest in public health, Kathryn plans to pursue a PhD in Bioengineering, focusing her research on creating accessible medical devices for global health applications.

Microfluidic Capture and Quantification of HIV