Background
Stroke is one of the leading causes of death and disability in adulthood worldwide. A simple and convenient diagnostic method is needed for monitoring high-risk patients for stroke. Few POCTs are available for stroke diagnosis. Soluble blood P-selectin is known as a biomarker for platelet aggregation. Increased expression of P-selectin is observed in coronary artery disease, acute myocardial infarction, stroke and peripheral arterial disease.
Conclusion
In this study, we proposed a three-layer filter membrane system that can separate biomarker- rich fractions from whole blood, simplifying the analysis process and improving sensitivity by using quantum dot-labeled antibodies to detect biomarkers. We hope that our system complements the advantages of POCT and can be applied to real clinical applications.
Methods
Plasma proteins in blood were separated using a three-layered filter system. Quantum dot and antibody were conjugated to detect biomarkers present in plasma and then measured with a fluorescence spectrophotometer.
Objective
A simple method that can measure the increased expression of P-selectin in stroke patients is intended to be used for diagnosis or early detection and hospital monitoring of ischemic stroke.
Results
The detection limit of soluble P-selectin confirmed by immunoassay was 1 ng/ul. In order to increase the sensitivity and simplify the reaction, the detection limit was measured to evaluate the sensitivity of the quantum dot labeled anti P-selectin antibody. As a result, P-selectin of 5 ng/ul or more showed saturation signal intensity, indicating the upper limit of detection, and 10 pg/ul was the lower limit of detection.