In this work, a very simple electrochemical HIV-1 protease biosensor useful for the development of an inexpensive lab-on-a- chip (LOC) device was constructed. The detection mechanism was designed to minimize the complexity either in the recognition receptor immobilization step or during the detection itself. The magnetic self-assembled monolayer of HIV-1 protease substrate peptide was able to detect as low as 10 pg/ml of the protease within 25 minutes with high specificity.
We are presenting cassette as a novel point of care diagnostic device. This device is easy to use, low cost to prepare, high throughput and can analyze several samples at the same time. We first, demonstrate the preparation method of the device. Then, fabrication of the flexible substrate has been presented. The device has been used for detection of the real sample of E.coli bacteria following by colorimetric detection. We have shown that we could detect 30 cfu/ml bacteria and 100 fg/μl of Staphylococous aureus DNA in 1 hr using LAMP amplification technique. This device will be helpful in hospitals and doctor’s office for analysis of several patients’ samples at the same time.
Long-period grating assisted Michelson interferometer has been proved to be a perspective device for chemical and
biochemical sensing based on refractive index measurement. However, the phase difference between the fiber core
propagation and the fiber cladding propagation in the in-fiber Michelson interferometer is correlated to the common
path length. As a result, the fringe spacing in the reflection spectrum drops with the interferometer cavity length, leading
to reduced fringe wave length shift in refractometry measurement. In this paper, we proposed a long-period grating
assisted Michelson interferometer with the core mode and the cladding mode propagation separated. By eliminating the
residue core mode after the long period grating coupling, an interferometer arm consists of cladding mode propagation
is realized. With the cavity length of the other arm controllable, the fringe spacing in the reflection spectrum of the
Michelson interferometer can be precisely controlled. The proposed Michelson interferometer allows use of long cavity
length of the cladding mode arm to accumulate phase change and large fringe spacing for wavelength interrogation in
A rapid, label-free on-line virus detection method has been developed based on opto-fluidic ring resonator (OFRR). The OFRR employs a fused silica capillary with a diameter around 100 μm. The circular cross section of the capillary forms the ring resonator that supports the whispering gallery modes (WGMs). The OFRR wall is only a few micrometers. Thus, the evanescent field of the WGMs extends into the core and interacts with the sample flowing in the core. The WGM spectral position shifts in response to the binding of biomolecules to the OFRR inner surface, providing quantitative and kinetic information about the biomolecule interaction. In this work, M13 filamentous phage and anti-M13 antibody are chosen as a model system to demonstrate the detection and quantification of virus in liquid samples. Anti-M13 antibodies are first covalently attached on the aminosilane coated OFRR surface to provide a bioselective layer. The detection is then performed when the virus concentration varies from 1011 pfu/mL down to 103 pfu/mL. Our experimental results show that the OFRR is capable of detecting M13 at a concentration as low as 1000 pfu/mL. Control experiments are carried out to show the specificity of the detection. A theoretical model is developed to analyze the experimental results. The OFRR are advantageous in virus detection, as it integrates the ring resonator with fluidic channels and provides continuous on-line monitoring capability. It also has great potential for sensitive, rapid, and low-cost micro total analysis devices for biomolecule detection.
Conference Committee Involvement (4)
Photonic Microdevices/Microstructures for Sensing IV
26 April 2012 | Baltimore, Maryland, United States
Photonic Microdevices/Microstructures for Sensing III
27 April 2011 | Orlando, Florida, United States
Photonic Microdevices/Microstructures for Sensing II