TY - JOUR
T1 - A low cost mobile phone dark-field microscope for nanoparticle-based quantitative studies
AU - Sun, Dali
AU - Hu, Ye
N1 - Funding Information:
This research was supported in part by US National Institute of Allergy and Infectious Diseases grant R01Al113725-01A1 and R01AI122932-01A1 to YH. Authors would like to thank Drs. Christopher J. Lyon, Chang Liu, and Jia Fan for their invaluable advice. D.S. designed the study and conducted the experiments. The authors declare no competing financial interest.
Publisher Copyright:
© 2017
PY - 2018/1/15
Y1 - 2018/1/15
N2 - Dark-field microscope (DFM) analysis of nanoparticle binding signal is highly useful for a variety of research and biomedical applications, but current applications for nanoparticle quantification rely on expensive DFM systems. The cost, size, limited robustness of these DFMs limits their utility for non-laboratory settings. Most nanoparticle analyses use high-magnification DFM images, which are labor intensive to acquire and subject to operator bias. Low-magnification DFM image capture is faster, but is subject to background from surface artifacts and debris, although image processing can partially compensate for background signal. We thus mated an LED light source, a dark-field condenser and a 20× objective lens with a mobile phone camera to create an inexpensive, portable and robust DFM system suitable for use in non-laboratory conditions. This proof-of-concept mobile DFM device weighs less than 400 g and costs less than $2000, but analysis of images captured with this device reveal similar nanoparticle quantitation results to those acquired with a much larger and more expensive desktop DFMM system. Our results suggest that similar devices may be useful for quantification of stable, nanoparticle-based activity and quantitation assays in resource-limited areas where conventional assay approaches are not practical.
AB - Dark-field microscope (DFM) analysis of nanoparticle binding signal is highly useful for a variety of research and biomedical applications, but current applications for nanoparticle quantification rely on expensive DFM systems. The cost, size, limited robustness of these DFMs limits their utility for non-laboratory settings. Most nanoparticle analyses use high-magnification DFM images, which are labor intensive to acquire and subject to operator bias. Low-magnification DFM image capture is faster, but is subject to background from surface artifacts and debris, although image processing can partially compensate for background signal. We thus mated an LED light source, a dark-field condenser and a 20× objective lens with a mobile phone camera to create an inexpensive, portable and robust DFM system suitable for use in non-laboratory conditions. This proof-of-concept mobile DFM device weighs less than 400 g and costs less than $2000, but analysis of images captured with this device reveal similar nanoparticle quantitation results to those acquired with a much larger and more expensive desktop DFMM system. Our results suggest that similar devices may be useful for quantification of stable, nanoparticle-based activity and quantitation assays in resource-limited areas where conventional assay approaches are not practical.
KW - Dark field microscope
KW - ImageJ
KW - Immunoassay
KW - Mobile phone
KW - Nanoparticle
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U2 - 10.1016/j.bios.2017.08.025
DO - 10.1016/j.bios.2017.08.025
M3 - Article
C2 - 28823976
AN - SCOPUS:85027517976
SN - 0956-5663
VL - 99
SP - 513
EP - 518
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
ER -