Escherichia coil Fiber Sensors Using Concentrated Dielectrophoretic Force with Optical Defocusing Method

被引：8

作者：

Tai, Yi-Hsin ^{[1
]}

Lee, Chia-Wei ^{[1
]}

Chang, Dao-Ming ^{[2
]}

Lai, Yu-Sheng ^{[3
]}

Huang, Ding-Wei ^{[4
]}

Wei, Pei-Kuen ^{[1
,5
,6
]}

机构：

[1] Acad Sinica, Res Ctr Appl Sci, Taipei 11529, Taiwan

[2] Natl Taiwan Univ, Dept Biochem Sci & Technol, Taipei 10617, Taiwan

[3] Natl Taiwan Univ, Coll Med, Dept Biochem & Mol Biol, Taipei 10051, Taiwan

[4] Natl Taiwan Univ, Grad Inst Photon & Optoelect, Taipei 10617, Taiwan

[5] Natl Yang Ming Univ, Inst Biophoton, Taipei 11221, Taiwan

[6] Natl Taiwan Ocean Univ, Inst Optoelect Sci, Keelung 20224, Taiwan

来源：

ACS SENSORS | 2018年 / 3卷 / 06期

关键词：

fiber tip; defocused image; refractive index detection; dielectrophoretic force; E; coli; SURFACE-PLASMON RESONANCE; GRATINGS; FLUORESCENCE; ENHANCEMENT; SENSITIVITY; ALUMINUM; POINTS;

D O I：

10.1021/acssensors.8b00258

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A sensitive tapered optical fiber tip combined with dielectrophoretic (DEP) trapping was used for rapid and label free detection of bacteria in water. The angular spectrum of the optical field at the fiber tip was changed with the surrounding refractive index (RI). By measuring far-field intensity change at the defocus plane, the intensity sensitivity was up to 95 200%/RIU (RI unit), and the detection limit was 5.2 x 10(-6) RIU at 0.5% intensity stability. By applying an AC voltage to a Ti/Al coated fiber tip and an indium tin-oxide glass, the DEP force effectively trapped the Escherichia coli (E. coil) near the fiber tip. Those bacteria can be directly measured from optical intensity change due to the increase of surrounding RI. By immobilizing the antibody on the Ti/Al fiber tip, the tests for specific K12 bacteria and nonspecific BL21 bacteria verified the specificity. The antibody-immobilized Ti/Al coated fiber tip with DEP trapping can detect bacteria at a concentration about 100 CFU/mL.

引用

页码：1196 / 1202

页数：13

共 36 条

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