Open AccessSilicon Photomultipliers as a Low-Cost Fluorescence Detector for Capillary Electrophoresis
Author(s) -
Brae V. Petersen,
Luke Gallion,
Nancy L. Allbritton
Publication year - 2020
Publication title -
analytical chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.117
H-Index - 332
eISSN - 1520-6882
pISSN - 0003-2700
DOI - 10.1021/acs.analchem.0c03105
Subject(s) - silicon photomultiplier , detector , chemistry , photomultiplier , detection limit , capillary electrophoresis , instrumentation (computer programming) , sensitivity (control systems) , cascade , microscale chemistry , dynamic range , scintillator , optoelectronics , optics , physics , chromatography , electronic engineering , computer science , engineering , mathematics education , mathematics , operating system
Capillary electrophoresis (CE) is a highly efficient separation method capable of handling small sample volumes (∼pL) and low (∼yoctomole) detection limits and, as such, is ideal for applications that require high sensitivity, such as single-cell analysis (Chen et al. Anal. Chem. 1996 , 68 (4), 690-696; Cohen et al. Annu. Rev. Anal. Chem. 2008 , 1 (1), 165-190; Vickerman et al. ACS Chem. Biol. 2018 , 13 (7), 1741-1751). Low-cost CE instrumentation is quickly expanding, but low-cost, open-source fluorescence detectors with ultrasensitive detection limits are lacking (Vickerman et al. ACS Chem. Biol. 2018 , 13 (7), 1741-1751; Fang et al. Electrophoresis 2016 , 37 (17-18), 2376-2383; Casto et al. Anal. Chem. 2019 , 40 (1), 65-78). Silicon photomultipliers (SiPM) are inexpensive, low-footprint detectors with the potential to fill the role as a detector when cost, size, and customization are important. In this work, we demonstrate the use of a SiPM in CE with zeptomolar detection limits and a dynamic range spanning 5 orders of magnitude, comparable to photomultiplier detectors. The performance of these detectors was measured using a continuous wave excitation laser in an epifluorescence detection configuration. We characterize the performance of the SiPM as a highly sensitive detector by measuring enzyme activity in single cells. This simple, small footprint, and low-cost (<$130) light detection circuit will be beneficial for open-source, portable, and budget-friendly instrumentation requiring high sensitivity.