In-situ detection of density alteration in non-physiological cells with polarimetric tilted fiber grating sensors.
Tilted fiber Bragg grating (TFBG) biosensors can be used as a cost-effective and relatively simple-to-implement alternative to well established biosensor platforms for high sensitivity biological sample measurements in situ or possibly in vivo. The fiber biosensor presented in this study utilizes an in-fiber 12° tilted Bragg grating to excite a strong evanescent field on the surface of the sensor over a large range of external medium refractive indices. The devices have minimal cross-sensitivity to temperature and their fabrication does not impact the structural integrity of the fiber and its surface functionalization. Human acute leukemia cells with different intracellular densities and refractive index (RI) ranging from 1.3342 to 1.3344 were clearly discriminated in-situ by using the differential transmission spectrum between two orthogonal polarizations for the last guided mode resonance before "cut-off", with an amplitude variation sensitivity of 1.8 × 10(4) dB/RIU, a wavelength shift sensitivity of 180 nm/RIU, and a limit of detection of 2 × 10(-5)RIU. The detection process was precisely controlled with a micro-fluidic chip which allows the measurement of nL-volumes of bio-samples. The proposed in-fiber polarimetric biosensor is an appealing solution for rapid, sub-microliter dose and highly sensitive detection of analytes at low concentrations in medicine, chemical and environmental monitoring.
Institute of Photonics Technology, Jinan University, Guangzhou 510632, China.
Tuan
T
Guo
Institute of Photonics Technology, Jinan University, Guangzhou 510632, China.
Fu
F
Liu
Department of Biochemistry, Medical School, Jinan University, Guangzhou 510632, China.
Yu
Y
Liu
Department of Electro-Optical Engineering, National United University, Miaoli 360, Taiwan.
Nan-Kuang
NK
Chen
Institute of Photonics Technology, Jinan University, Guangzhou 510632, China. Electronic address: tguanbo@jnu.edu.cn.
Bai-Ou
BO
Guan
Department of Electronics, Carleton University, 1125 Colonel By Drive, Ottawa, Canada, K1S 5B6. Electronic address: jacques_albert@carleton.ca.
Jacques
J
Albert
D015374:Biosensing Techniques / Q000295:instrumentation*; D002452:Cell Count / Q000295:instrumentation*; D003720:Densitometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D020014:K562 Cells; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
Density alteration in non-physiological cells; Optical biosensor; Optical fiber; Polarimetric fiber grating