Integrated microfluidic systems with an immunosensor modified with carbon nanotubes for detection of prostate specific antigen (PSA) in human serum samples

Prostate-specific antigen (PSA) is the established routine screening tool for the detection of early-stage prostate cancer. Given the laboratory-centric nature of the process, the development of a portable, ultra rapid high-throughput system for PSA screening is highly desirable. In this study, an advancedpoint-of-care system for PSA detection in human serum was developed based on a cellular biosensor where the cell membrane was modified by electroinserting a specific antibody against PSA. Thirty nine human serum samples were used for validation of this biosensory system for PSA detection. Samples were analyzed in parallel with a standard immunoradiometric assay (IRMA) and an established electrochemical immunoassay was used for comparison purposes. They were classified in three different PSA concentration ranges (0, <4 and ≥4 ng/mL). Cells membrane-engineered with 0.25 μg/mL anti-PSA antibody demonstrated a statistically lower response against the upper (≥4 ng/mL) PSA concentration range. In addition, the cell-based biosensor performed better than the immunosensor in terms of sensitivity and resolution against positive samples containing <4 ng/mL PSA. In spite of its preliminary, proof-of-concept stage of development, the cell-based biosensor could be used as aninitiative for the development of a fast, low-cost, and high-throughput POC screening system for PSA.

Download Full-text

Simultaneous Multianalyte ELISA Performed on a Microarray Platform

Clinical Chemistry ◽

10.1093/clinchem/47.8.1451 ◽

2001 ◽

Vol 47 (8) ◽

pp. 1451-1457 ◽

Cited By ~ 128

Author(s):

Rick Wiese ◽

Yuri Belosludtsev ◽

Tom Powdrill ◽

Patricia Thompson ◽

Mike Hogan

Keyword(s):

Human Serum ◽

Calibration Curve ◽

Sandwich Elisa ◽

Specific Antigen ◽

Simultaneous Detection ◽

Microarray Platform ◽

Microtiter Plate ◽

Serum Samples ◽

Human Serum Samples ◽

Calibration Curves

Abstract Background: A logical progression of the widely used microtiter plate ELISA is toward a protein array format that allows simultaneous detection of multiple analytes at multiple array addresses within a single well. Here we describe the construction and use of such a multiplex ELISA to measure prostate-specific antigen (PSA), α1-antichymotrypsin-bound PSA (PSA-ACT), and interleukin-6 (IL-6). Methods: We silanized glass plates and printed the appropriate capture antibodies to allow for the construction of “sandwich” ELISA quantification assays. We examined specificity of the assay for appropriate antigen, assembled calibration curves, and obtained PSA concentrations for 14 human serum samples. We compared the serum PSA concentrations derived through the use of our array with values obtained independently using a standard ELISA method. Results: R 2 values generated by our microarray for the PSA and PSA-ACT calibration curves were 0.989 and 0.979, respectively. Analyte concentrations used for the construction of these curves were 0.31–20 μg of protein/L of diluent. IL-6 calibration curve concentrations were 4.9–300 ng of IL-6/L of diluent. The R2 value for the IL-6 calibration curve was 0.983. The 14 human serum samples screened by this micro-ELISA technique for PSA concentrations generated a regression equation (linear) with a slope of 0.83 ± 0.10 and intercept of 0.74 ± 0.70 (R2 = 0.88). Conclusions: Multiplexed ELISA arrays are a feasible option for analyte quantification in complex biologic samples.

Download Full-text

Carbon Nanotubes Modified Electrode for Enhanced Voltammetric Sensing of Mebeverine Hydrochloride in Formulations and Human Serum Samples

Journal of The Electrochemical Society ◽

10.1149/2.0941706jes ◽

2017 ◽

Vol 164 (6) ◽

pp. B212-B222 ◽

Cited By ~ 12

Author(s):

Hanaa S. El-Desoky ◽

Mohamed M. Ghoneim ◽

Fared M. El-badawy

Keyword(s):

Carbon Nanotubes ◽

Human Serum ◽

Modified Electrode ◽

Serum Samples ◽

Human Serum Samples ◽

Mebeverine Hydrochloride ◽

Voltammetric Sensing

Download Full-text

Simultaneous Monitoring of Febuxostat and Uric Acid in Human Serum Samples Using the Direct Square-Wave Voltammetric Method

Current Analytical Chemistry ◽

10.2174/1573411014666180730112905 ◽

2019 ◽

Vol 15 (6) ◽

pp. 678-684

Author(s):

Biljana Nigović ◽

Jakov Vlak

Keyword(s):

Uric Acid ◽

Human Serum ◽

Oxidase Inhibitor ◽

Serum Samples ◽

Boron Doped Diamond ◽

Fast Analysis ◽

Xanthine Oxidase Inhibitor ◽

Voltammetric Method ◽

Square Wave ◽

Human Serum Samples

Background: High uric acid serum level, hyperuricemia, is now associated with many diseases such as gout, chronic kidney disease, hypertension, coronary artery disease and diabetes. Febuxostat is a novel selective xanthine oxidase inhibitor approved for the treatment of hyperuricemia. Objective: The aim of this study was to develop a first analytical method for the simultaneous determination of febuxostat and uric acid. Methods: An unmodified boron-doped diamond electrode provided concurrent quantitation of drug at low levels and uric acid, which has clinical significance in the diagnosis and therapy of hyperuricemia, at relatively high concentrations. The direct square-wave voltammetric method was applied to the analysis of both analytes in human serum samples. Results: Under the optimized conditions, the linear response of peak current on febuxostat concentration was achieved in the range from 7.5 × 10-7 to 3 × 10-5 M, while uric acid showed two linear ranges of 5 × 10-6 - 5 × 10-5 M and 5 × 10-5 - 2 × 10-4 M. The method was successfully utilised for quantification of both analytes in human serum samples. Good recoveries were obtained without interference from common inorganic cations and anions as well as glucose, dopamine, ascorbic and folic acids at concentrations expected in physiological conditions. Conclusion: The great benefits of developed method are fast analysis (only 7.5 s for run), low cost and simplicity of performance.

Download Full-text