Feasibility of a point-of-care test based on quantum dots with a mobile phone reader for detection of antibody responses

• Published in: PLoS neglected tropical diseases Vol. 13; no. 10; p. e0007746
• Main Authors: Lee, Chan, Noh, John, O’Neal, Seth E., Gonzalez, Armando E., Garcia, Hector H., Handali, Sukwan
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.10.2019; Public Library of Science (PLoS)
• Subjects: Animals; Antibodies; Antibodies, Helminth - blood; Antibody Formation; Antigens; Antigens, Helminth - immunology; Assaying; Biology and Life Sciences; Cell Phone; Cell phones; Cellular telephones; Computed tomography; Convulsions & seizures; Cysticercosis; Cysts; Detection; Disease control; Engineering and Technology; Enzymes; Epilepsy; Feasibility Studies; Fluorescence; Health aspects; Humans; Imaging techniques; Immunologic Tests - methods; Magnetic Resonance Imaging; Medical imaging; Medicine and Health Sciences; Nanoparticles; Neurocysticercosis - diagnosis; Neurocysticercosis - immunology; Neurology; Novels; Parasitic diseases; Physical Sciences; Point of care testing; Povidone; Protocols; Quantum Dots; Research and Analysis Methods; Retrospective Studies; Samples; Sensitivity and Specificity; Sensors; Serum; Specificity; Taenia solium; Tomography; Tropical diseases; Working groups; Oregon; Atlanta Georgia; Georgia; United States > US; Peru
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0007746

We developed a novel and portable fluorescent sensor that integrates a lateral flow assay with a quantum dot (Qdots) label and a mobile phone reader for detection of specific antibodies in human serum. We evaluated the utility of this assay to test for antibodies to the Taenia solium rT24H antigen. It was a retrospective study by examining 112 positive human sera from patients with neurocysticercosis (NCC) including samples from patients with single viable cyst (n = 18), two or more viable cysts (n = 71), and subarachnoid (racemose) cysts (n = 23). These samples were collected from previous study subjects in Lima, Peru under an approved study protocol in Peru. The sera were made anonymous under a protocol approved by the CDC Institutional Review Board. Definitive diagnosis of the subject was established by computed-tomography and/or magnetic resonance imaging. To test the specificity of the assay, we evaluated a panel of serum samples obtained from patients with other infections (n = 24), and serum samples from persons in the United States and Egypt who had not traveled outside their country, and therefore are presumed negative for cysticercosis (n = 128). The assay specificity in the negative panel was 99% (95-100%) while assay sensitivity was 89% (79-95%) in NCC patients with two or more viable cysts. Our assay has performance characteristics similar to those of traditional platforms for the detection of NCC and shows promise as a mobile phone reader-based point-of-care test for antibody detection.