Open AccessAn integrated microfluidic platform for selective and real-time detection of thrombin biomarkers using a graphene FET
Author(s) -
Niazul Islam Khan,
Mohammad Mousazadehkasin,
Sujoy Ghosh,
John G. Tsavalas,
Edward Song
Publication year - 2020
Publication title -
analyst (london. 1877. online)/analyst
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.998
H-Index - 153
eISSN - 1364-5528
pISSN - 0003-2654
DOI - 10.1039/d0an00251h
Subject(s) - aptamer , detection limit , biosensor , analyte , microfluidics , graphene , nanotechnology , lab on a chip , materials science , point of care , calibration curve , raman spectroscopy , analytical chemistry (journal) , chemistry , chromatography , physics , medicine , genetics , nursing , optics , biology
Lab-on-a-chip technology offers an ideal platform for low-cost, reliable, and easy-to-use diagnostics of key biomarkers needed for early screening of diseases and other health concerns. In this work, a graphene field-effect transistor (GFET) functionalized with target-binding aptamers is used as a biosensor for the detection of thrombin protein biomarker. Furthermore, this GFET is integrated with a microfluidic device for enhanced sensing performances in terms of detection limit, sensitivity, and continuous monitoring. Under this platform, a picomolar limit of detection was achieved for measuring thrombin; in our experiment measured as low as 2.6 pM. FTIR, Raman and UV-Vis spectroscopy measurements were performed to confirm the device functionalization steps. Based on the concentration-dependent calibration curve, a dissociation constant of K D = 375.8 pM was obtained. Continuous real-time measurements were also conducted under a constant gate voltage (V GS ) to observe the transient response of the sensor when analyte was introduced to the device. The target selectivity of the sensor platform was evaluated and confirmed by challenging the GFET biosensor with various concentrations of lysozyme protein. The results suggest that this device technology has the potential to be used as a general diagnostic platform for measuring clinically relevant biomarkers for point-of-care applications.