Fabrication of core-shell quantum dots microbeads with high stability, enhanced sensitivity and potential application in C-reactive protein (CRP) and procalcitonin (PCT) immunochromatography in vitro diagnostic reagents

Cardiovascular and cerebrovascular diseases represent the leading causes of mortality among middle-aged and elderly populations in China, with inflammation identified as a significant contributing factor. Consequently, the early diagnosis and management of inflammation are of paramount importance. C-reactive protein (CRP) and procalcitonin (PCT) serve as biomarkers for myocardial inflammation. In this study, we developed a quantum dot immunochromatographic strip that was capable of simultaneously detecting these two biomarkers with enhanced sensitivity and specificity. The comb amphiphilic poly (octadecyl-alt-polyethylene glycol) was synthesized through an amide reaction, which was employed to coat oil-soluble quantum dots, thereby transforming them into water-soluble quantum dots microbeads suitable for the coupling with biological macromolecules. These quantum dots microbeads were utilized as luminescent materials in the immunochromatographic strip for the concurrent detection of CRP and PCT. The assay required only 100 µL of sample and provided results within 10 min, demonstrating commendable precision, stability, sensitivity, and accuracy. Clinical evaluations confirmed that the developed CRP and PCT quantum dots immunochromatographic test strips were accurate and reliable, underscoring their significant potential for practical routine clinical application in the early accurate diagnosis of myocardial inflammation.