Ambient light-based optical biosensing platform with smartphone-embedded illumination sensor.
We present a hand-held optical biosensing system utilizing a smartphone-embedded illumination sensor that is integrated with immunoblotting assay method. The smartphone-embedded illumination sensor is regarded as an alternative optical receiver that can replaces the conventional optical analysis apparatus because the illumination sensor can respond to the ambient light in a wide range of wavelengths, including visible and infrared. To demonstrate the biosensing applicability of our system employing the enzyme-mediated immunoblotting and accompanying light interference, various types of ambient light conditions including outdoor sunlight and indoor fluorescent were tested. For the immunoblotting assay, the biosensing channel generating insoluble precipitates as an end product of the enzymatic reaction is fabricated and mounted on the illumination sensor of the smartphone. The intensity of penetrating light arrives on the illumination sensor is inversely proportional to the amount of precipitates produced in the channel, and these changes are immediately analyzed and quantified via smartphone software. In this study, urinary C-terminal telopeptide fragment of type II collagen (uCTX-II), a biomarker of osteoarthritis diagnosis, was tested as a model analyte. The developed smartphone-based sensing system efficiently measured uCTX-II in the 0-5ng/mL concentration range with a high sensitivity and accuracy under various light conditions. These assay results show that the illumination sensor-based optical biosensor is suitable for point-of-care testing (POCT).
Department of Molecular Science and Technology, Ajou University, Suwon, 443749 South Korea.
Yoo Min
YM
Park
Department of Molecular Science and Technology, Ajou University, Suwon, 443749 South Korea.
Yong Duk
YD
Han
Department of Molecular Science and Technology, Ajou University, Suwon, 443749 South Korea.
Hyeong Jin
HJ
Chun
Department of Molecular Science and Technology, Ajou University, Suwon, 443749 South Korea. Electronic address: hcyoon@ajou.ac.kr.
Hyun C
HC
Yoon
D015374:Biosensing Techniques; D024043:Collagen Type II / Q000737:chemistry*; D003124:Colorimetry; D008027:Light; D008029:Lighting; D055096:Optical Devices; D000067716:Point-of-Care Testing; D000068997:Smartphone
D024043:Collagen Type II
Ambient light condition; Illumination sensor; Osteoarthritis; Smartphone-based biosensor