Skip to main content
. Author manuscript; available in PMC: 2022 Apr 7.
Published in final edited form as: Sci Transl Med. 2021 Apr 7;13(588):eabd9696. doi: 10.1126/scitranslmed.abd9696

Fig. 4. The D4Scope, a handheld fluorescence detector.

Fig. 4.

(A) Photograph of the D4Scope. (B) Three-dimensional design, highlighting core components and computer-on-a-chip–based architecture, with an integrated touchscreen and CMOS camera. (C) D4Scope illumination scheme, depicting oblique angle laser excitation (at a 45° angle to the surface of the D4 chip), bandpass filter, and Raspberry Pi 4 processing unit. (D) Dose-response curve obtained by plotting fluorescence intensity measured by D4Scope versus concentration of EBOV sGP spiked into pooled HS. Inset: Comparison of fluorescence readout using a GenePix scanner and the D4Scope. (E) Dose-response curve for EBOV sGP spiked into rhesus MoS imaged by a technician using the D4Scope at the Galveston National Laboratory (GNL; BSL-4) after a 30-min training session. Inset: Comparison of fluorescence readouts from SensoSpot fluorescence scanner and D4Scope at GNL. (F) Double-blinded spiked analyte recovery experiment at GNL, with sGP concentrations in rhesus MoS determined by fluorescence intensity using D4Scope and SensoSpot scanner. D4 assay data point represents the mean ± SEM of N = 4 independent assays; blinded analyte recovery data points represent the mean of N = 3 technical replicates.