EAPSI: Portable Smartphone-Based Detection of Vaspin Protein in Human Blood Serum

Ulep Tiffany-Heathert, Tucson AZ

Investigators

Abstract

Vaspin, a protein secreted from fat tissue, has been shown in numerous studies to be closely related to type 2 diabetes, insulin sensitivity, obesity, and glucose metabolism. Aptamers, highly stable and specific molecular probes, can be linked onto gold nanoparticles for its use in biosensor applications. This project will explore the use of this vaspin targeting gold nanoparticle in a paper microfluidic assay as a cheaper, disposable, and portable colorimetric indicator. A smartphone-integrated capability will be designed, developed, and used for image analysis to detect vaspin concentration in human blood serum. The aim of this project is to fabricate a portable, low cost, point of care (POC) system that can be used for diagnostics and monitoring for insulin-related metabolism in areas of low resources and accessibilities. This research will be conducted in collaboration with Dr. Man Bock Gu, a noted expert on aptamer production, characterization, and analysis, at Korea University. In numerous studies Vaspin, an adipocytokine secreted from adipose tissue, has been closely related to type 2 diabetes, insulin sensitivity, obesity, and glucose metabolism. Aptamers, oligonucleotide sequences that can specifically bind to certain molecules of interest, have been a topic of interest in biosensors for its biocompatibility, low cost, and chemical stability in comparison to antibodies. A newly-developed cognate duo aptamer (V1 and V49) targets vaspin at two different binding sites, further increasing specificity and affinity. Aptamer-gold nanoparticle (aptamer-AuNP) conjugations were used as biosensors to detect and measure vaspin concentrations in both buffer solutions and human blood serum dilutions via sandwich-type surface plasmon resonance (SPR) gold chips. Using this vaspin targeting aptamer-AuNP conjugate, a colorimetric paper microfluidic assay can be developed with use of smart-phone-integrated capabilities and analysis. The aim of this project is to fabricate a portable, low cost, point of care (POC), diagnostic system that will be beneficial to areas of low resources and accessibility to healthcare. This award, under the East Asian and Pacific Summer Institutes program, supports summer research by a U.S. graduate student and is jointly funded by NSF and the National Research Foundation of Korea.