A low-cost smartphone-based platform for highly sensitive point-of-care testing with persistent luminescent phosphors.
Through their computational power and connectivity, smartphones are poised to rapidly expand telemedicine and transform healthcare by enabling better personal health monitoring and rapid diagnostics. Recently, a variety of platforms have been developed to enable smartphone-based point-of-care testing using imaging-based readout with the smartphone camera as the detector. Fluorescent reporters have been shown to improve the sensitivity of assays over colorimetric labels, but fluorescence readout necessitates incorporating optical hardware into the detection system, adding to the cost and complexity of the device. Here we present a simple, low-cost smartphone-based detection platform for highly sensitive luminescence imaging readout of point-of-care tests run with persistent luminescent phosphors as reporters. The extremely bright and long-lived emission of persistent phosphors allows sensitive analyte detection with a smartphone by a facile time-gated imaging strategy. Phosphors are first briefly excited with the phone's camera flash, followed by switching off the flash, and subsequent imaging of phosphor luminescence with the camera. Using this approach, we demonstrate detection of human chorionic gonadotropin using a lateral flow assay and the smartphone platform with strontium aluminate nanoparticles as reporters, giving a detection limit of ≈45 pg mL-1(1.2 pM) in buffer. Time-gated imaging on a smartphone can be readily adapted for sensitive and potentially quantitative testing using other point-of-care formats, and is workable with a variety of persistent luminescent materials.
Department of Chemical & Biomolecular Engineering, University of Houston, USA. willson@uh.edu and Luminostics, Inc., Houston, TX, USA.
Andrew S
0000-0001-7627-2393
AS
Paterson
Department of Chemical & Biomolecular Engineering, University of Houston, USA. willson@uh.edu and Luminostics, Inc., Houston, TX, USA.
Balakrishnan
B
Raja
Luminostics, Inc., Houston, TX, USA and Department of Mechanical Engineering, University of Houston, USA.
Vinay
V
Mandadi
Luminostics, Inc., Houston, TX, USA.
Blane
B
Townsend
Luminostics, Inc., Houston, TX, USA.
Miles
M
Lee
Department of Computer Science, University of Houston, USA.
Alex
A
Buell
Department of Chemical & Biomolecular Engineering, University of Houston, USA. willson@uh.edu.
Binh
B
Vu
Department of Chemistry, University of Houston, USA.
Jakoah
J
Brgoch
Department of Chemical & Biomolecular Engineering, University of Houston, USA. willson@uh.edu and Department of Biology & Biochemistry, University of Houston, USA and Centro de Biotecnología FEMSA, Tecnológico de Monterrey, Campus Monterrey, Mexico.
Richard C
RC
Willson
D006063:Chorionic Gonadotropin / Q000652:urine; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D057230:Limit of Detection; D049408:Luminescent Agents / Q000032:analysis / Q000737:chemistry*; D008163:Luminescent Measurements / Q000191:economics / Q000295:instrumentation / Q000379:methods; D000067716:Point-of-Care Testing; D000068997:Smartphone
D006063:Chorionic Gonadotropin; D049408:Luminescent Agents