title: Engineering long shelf life multi-layer biologically active surfaces on microfluidic devices for point of care applications.
abstract: Although materials and engineered surfaces are broadly utilized in creating assays and devices with wide applications in diagnostics, preservation of these immuno-functionalized surfaces on microfluidic devices remains a significant challenge to create reliable repeatable assays that would facilitate patient care in resource-constrained settings at the point-of-care (POC), where reliable electricity and refrigeration are lacking. To address this challenge, we present an innovative approach to stabilize surfaces on-chip with multiple layers of immunochemistry. The functionality of microfluidic devices using the presented method is evaluated at room temperature for up to 6-month shelf life. We integrated the preserved microfluidic devices with a lensless complementary metal oxide semiconductor (CMOS) imaging platform to count CD4(+) T cells from a drop of unprocessed whole blood targeting applications at the POC such as HIV management and monitoring. The developed immunochemistry stabilization method can potentially be applied broadly to other diagnostic immuno-assays such as viral load measurements, chemotherapy monitoring, and biomarker detection for cancer patients at the POC.
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Department of Radiology, Canary Center at Stanford for Cancer Early Detection, Stanford University School of Medicine, Electrical Engineering Department (by courtesy), Stanford University, Palo Alto, CA 94304.|Department of Electrical &Computer Engineering and Computer Science, Florida Atlantic University, Boca Raton FL, 33431.
authors.forename: Waseem
authors.initials: W
authors.lastname: Asghar
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Division for Biomedical Engineering, Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA.|Başkent University, Faculty of Engineering, Biomedical Engineering Department, Ankara, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Yuksekkaya
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Division for Biomedical Engineering, Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA.
authors.forename: Hadi
authors.initials: H
authors.lastname: Shafiee
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Division for Biomedical Engineering, Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Department of Radiology, Canary Center at Stanford for Cancer Early Detection, Stanford University School of Medicine, Electrical Engineering Department (by courtesy), Stanford University, Palo Alto, CA 94304.
authors.forename: Mehmet O
authors.initials: MO
authors.lastname: Ozen
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Department of Radiology, Canary Center at Stanford for Cancer Early Detection, Stanford University School of Medicine, Electrical Engineering Department (by courtesy), Stanford University, Palo Alto, CA 94304.
authors.forename: Fatih
authors.initials: F
authors.lastname: Inci
authors.affiliation: Başkent University, Faculty of Engineering, Biomedical Engineering Department, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kocakulak
authors.affiliation: Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Department of Radiology, Canary Center at Stanford for Cancer Early Detection, Stanford University School of Medicine, Electrical Engineering Department (by courtesy), Stanford University, Palo Alto, CA 94304.|Bio-Acoustic-MEMS in Medicine (BAMM) Laboratory, Division for Biomedical Engineering, Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA.
authors.forename: Utkan
authors.initials: U
authors.lastname: Demirci
mesh_terms: D018791:CD4 Lymphocyte Count / Q000295:instrumentation / Q000379:methods; D006801:Humans; D056656:Lab-On-A-Chip Devices; D046210:Microfluidic Analytical Techniques; D019095:Point-of-Care Systems