Surface lattice resonance of line array of poly (glycidyl methacrylate) with CdS quantum dots for label-free biosensing

Feng-Ping Lin; Hui-Ling Hsu; Chi-Jung Chang; Sheng-Chi Lee; Jem-Kun Chen

doi:10.1016/j.colsurfb.2019.03.073

Surface lattice resonance of line array of poly (glycidyl methacrylate) with CdS quantum dots for label-free biosensing

Colloids Surf B Biointerfaces. 2019 Jul 1:179:199-207. doi: 10.1016/j.colsurfb.2019.03.073. Epub 2019 Apr 2.

Authors

Feng-Ping Lin¹, Hui-Ling Hsu², Chi-Jung Chang³, Sheng-Chi Lee⁴, Jem-Kun Chen⁵

Affiliations

¹ Department of Materials Science and Engineering, National Taiwan University of Science and Technology, 43, Sec 4, Keelung Rd., Taipei, 106, Taiwan, ROC; Institute of Preventive Medicine, National Defense Medical Center, 161, Sec. 6, Minquan E. Rd., Neihu Dist., New Taipei City, Taiwan, ROC.
² Institute of Preventive Medicine, National Defense Medical Center, 161, Sec. 6, Minquan E. Rd., Neihu Dist., New Taipei City, Taiwan, ROC.
³ Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung, 40724, Taiwan, ROC.
⁴ Department of Orthopediac Surgery, Pingtung Branch, Kaohsiung Veterans General Hospital, 1, Anping Lane 1, Zhao Sheng Road, Neibu Township, Pingtung County, Taiwan, ROC. Electronic address: osclee.tw@msa.hinet.net.
⁵ Department of Materials Science and Engineering, National Taiwan University of Science and Technology, 43, Sec 4, Keelung Rd., Taipei, 106, Taiwan, ROC; Applied Research Center for Thin-Film Metallic Glass, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan, ROC. Electronic address: jkchen@mail.ntust.edu.tw.

PMID: 30959232
DOI: 10.1016/j.colsurfb.2019.03.073

Abstract

One dimensional plasmonic grating is a kind of resonant electromagnetic wave absorber with a characteristic wavelength. This study focusses on one-dimensional plasmonic grating consisting of poly (glycidyl methacrylate) (PGMA) brushes and CdS quantum dots (CdQDs) fabrication and PGMA chains grafted on a primary substrate in a line array continued by the immobilization of biotin-modified CdQDs. PGMA brush line array (PBLA) of plasmonic grating exhibited an absorptance at 441 nm while at the same time, CdQDs immobilized with PBLA showed characteristic absorbance at 396 nm. The blue-shift from 441 nm matches the absorbance peak of biotin-modified CdQDs resulting in the enhancement of photoluminescence emission of CdQDs. With streptavidin incubation to assemble CdQDs at 50 nM, the significant decrease in grating height resulted in the red-shift of the absorbance peak to 536 nm. Due to the deviation in absorbance, the intensity of the PL emission decreased gradually with the increase in concentration of streptavidin. In addition, our results showed that streptavidin incubation altered the color reflected from the surface due to effective changes in the refractive index of the layer as well. The limit of detection of the grating for streptavidin detection was determined to be 50 nM. Thus, PBLA-CdQD has the potential to act as a highly-sensitive, label-free optical biosensor.

Keywords: CdS quantum dots; Line array; Line arrays; PGMA brush.

MeSH terms

Biosensing Techniques / methods*
Biotin / chemistry
Cadmium Compounds / chemistry*
Optical Phenomena
Polymethacrylic Acids / chemistry*
Quantum Dots / chemistry*
Staining and Labeling*
Sulfides / chemistry*
Surface Plasmon Resonance
X-Ray Diffraction

Substances

Cadmium Compounds
Polymethacrylic Acids
Sulfides
cadmium sulfide
polyglycidyl methacrylate
Biotin