Direct detection of fibrinogen in human plasma using electric-double-layer gated AlGaN/GaN high electron mobility transistors

Abstract

Fibrinogen found in blood plasma is an important protein biomarker for potentially fatal diseases such as cardiovascular diseases. This study focuses on the development of an assay to detect plasmatic fibrinogen using electrical double layer gated AlGaN/GaN high electron mobility transistor biosensors without complex sample pre-treatment methods used in the traditional assays. The test results in buffer solution and clinical plasma samples show high sensitivity, specificity, and dynamic range. The sensor exhibits an ultra-low detection limit of 0.5 g/l and a detection range of 0.5–4.5 g/l in 1× PBS with 1% BSA. The concentration dependent sensor signal in human serum samples demonstrates the specificity to fibrinogen in a highly dense matrix of background proteins. The sensor does not require complicated automation, and quantitative results are obtained in 5 min with <5 μl sample volume. This sensing technique is ideal for speedy blood based diagnostics such as POC (point of care) tests, homecare tests, or personalized healthcare.

Review—High Field Modulated FET Biosensors for Biomedical Applications

“…The target analytes tested include N terminal pro brain natriuretic peptide (NT-proBNP), C-reactive protein (CRP) and Fibrinogen. 35,37 The results from Figure 2 demonstrate that the high field gated FET biosensor exhibits high sensitivity over a wide dynamic range of detection, which spans the clinically relevant target analyte concentrations. Extensive sample pre-processing, additional labeling/reagents or washing processes are not required for the assay.…”

“…The sensing characteristics of the EDL FET biosensor are demonstrated through the detection of various clinical protein-based biomarkers in 1X PBS and human serum. 35,37 Figures 2b and 2c depict the sensor response curves for detection of human immunodeficiency virus 1-reverse transcriptase (HIV1-RT) protein and carcinoembryonic antigen (CEA), respectively, in buffer system. The purified proteins are prepared in 1X PBS with BSA added in it to simulate the physiological conditions of human blood plasma, as albumin is the most abundant protein in serum.…”

“…In this article, we will explore the different aspects of this high field gated FET biosensor 35 and (f) Fibrinogen detection. 37 and demonstrate the various applications in the field of biomedical engineering.…”

“…Total charge versus protein concentration in 1X PBS for (b) HIV-1 RT detection (c) CEA detection. Total charge versus protein concentration in human serum for (d) NT-proBNP detection (e) CRP detection35 and (f) Fibrinogen detection 37.…”

Aptamer-functionalized AlGaN/GaN High-electron-mobility Transistor for Rapid Diagnosis of Fibrinogen in Human Plasma

“…(13)(14)(15) Previously, we developed a FET biosensor-based method to directly detect protein biomarkers in human serum. (16)(17)(18)(19)(20)(21) In this study, we have developed an aptamerfunctionalized GaN HEMT biosensor to directly detect fibrinogen in untreated human plasma samples. The charge screening effect is eliminated using a high-field gating mechanism that is uniquely employed in this FET sensor methodology.…”