Next Article in Journal
Design and Optimization of an MFL Coil Sensor Apparatus Based on Numerical Survey
Previous Article in Journal
Iterative Positioning Algorithm for Indoor Node Based on Distance Correction in WSNs
Open AccessArticle

The Enhanced Sensitivity of a Porous Silicon Microcavity Biosensor Based on an Angular Spectrum Using CdSe/ZnS Quantum Dots

1
School of Physical Science and Technology, Xinjiang University, Urumqi 830046, China
2
School of Information Science and Engineering, Xinjiang University, Urumqi 830046, China
*
Author to whom correspondence should be addressed.
Sensors 2019, 19(22), 4872; https://doi.org/10.3390/s19224872
Received: 23 October 2019 / Revised: 4 November 2019 / Accepted: 6 November 2019 / Published: 8 November 2019
(This article belongs to the Section Biosensors)
To improve the detection sensitivity of porous silicon microcavity biosensors, CdSe/ZnS quantum dots are used to label complementary DNA molecules for the refractive index amplification and angular spectrum method for detection. In this method, the TE mode laser is used as the detection light and the light source is changed into a parallel beam by collimating and expanding the beam, which illuminates the PSM surface and receives the reflected light from the PSM surface through the detector. The angle corresponding to the weakest reflected light intensity before and after the biological reaction between probe DNA and complementary DNA of different concentrations labeled by quantum dots was measured by the detector, and the relationship between the angle change before and after the biological reaction and the complementary DNA concentration labeled by quantum dots was obtained. The experimental results show that the angle change increases linearly with increasing complementary DNA concentration. The detection limit of the experiment, as determined by fitting, is approximately 36 pM. The detection limit of this method is approximately 1/300 of that without quantum dot labeling. Our method has a low cost because it does not require the use of a reflectance spectrometer, and it also demonstrates high sensitivity. View Full-Text
Keywords: porous silicon microcavity; quantum dot; angular spectrum; refractive index amplification porous silicon microcavity; quantum dot; angular spectrum; refractive index amplification
Show Figures

Figure 1

MDPI and ACS Style

Zhou, R.; Jia, Z.; Lv, X.; Huang, X. The Enhanced Sensitivity of a Porous Silicon Microcavity Biosensor Based on an Angular Spectrum Using CdSe/ZnS Quantum Dots. Sensors 2019, 19, 4872.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop