|Title||Environmentally Resilient Microfluidic Point-of-Care Immunoassay Enables Rapid Diagnosis of Talaromycosis|
|Publication Type||Journal Article|
|Year of Publication||2023|
|Authors||Kinnamon, DS, Heggestad, JT, Liu, J, Nguyen, T, Ly, V, Hucknall, AM, Fontes, CM, Britton, RJ, Cai, J-P, Chan, JFuk-Woo, Yuen, K-Y, Le, T, Chilkoti, A|
Point-of-care tests (POCTs) are increasingly being used in field settings, particularly outdoors. The performance of current POCTs─most commonly the lateral flow immunoassay─can be adversely affected by ambient temperature and humidity. We developed a self-contained immunoassay platform─the D4 POCT─that can be conducted at the POC by integrating all reagents in a capillary-driven passive microfluidic cassette that minimizes user intervention. The assay can be imaged and analyzed on a portable fluorescence reader─the D4Scope─and provide quantitative outputs. Here, we systematically investigated the resilience of our D4 POCT to varied temperature and humidity and to physiologically diverse human whole blood samples that span a wide range of physiological hematocrit (30–65%). For all conditions, we showed that the platform maintained high sensitivity (0.05–0.41 ng/mL limits of detection). The platform also demonstrated good accuracy in reporting true analyte concentration across environmental extremes when compared to the manually operated format of the same test to detect a model analyte─ovalbumin. Additionally, we engineered an improved version of the microfluidic cassette that improved the ease-of-use of the device and shortened the time-to-result. We implemented this new cassette to create a rapid diagnostic test to detect talaromycosis infection in patients with advanced HIV disease at the POC, demonstrating comparable sensitivity and specificity to the laboratory test for the disease.
|Short Title||ACS Sens.|