A research team led by Henry Du of the Stevens Institute of Technology is investigating ways to enhance photonic crystal fiber (PCF) sensors, sensor arrays, and sensor networks for applications including remote and dynamic environmental monitoring, manufacturing process safety, medical diagnostics, and homeland security.
The work entails molecular and nanoscale surface modification, advanced laser techniques, and computer simulation. According to Du, the optically robust PCFs with surface-functionalized, axially aligned air holes will surpass conventional fiber-optic sensor technology for chemical and biological detection. The sensors could also prove a powerful research platform for in situ fundamental studies of surface chemistry and chemical/biological interactions in microchemical and microbiological systems.
The PCFs will be fabricated by means of a modified sol-gel method for optical fibers with the aid of simulation-based design for optimum light-analyte interactions. The functionalized hollow core or cladding air holes will be filled with analytes to evaluate PCF sensing capabilities. Nanoscale surface functionalization will be achieved with two strategies:
- 1. Surface attachment of Ag nanoparticles mediated by 3-mercaptopropyltrimethoxysilane self-assembled monolayer (SAM) for chemical sensing of NOX, CO, and SO2, where surface-enhanced Raman scattering (SERS) can be exploited for high sensitivity and molecular specificity
- 2. Surface binding of biospecific recognition entities for biological sensing using certain recognition pairs—biotin/ avidin, cholera toxin/antitoxin, and organophosphorous hydrolase/paraoxon, where SERS may also be exploited.
In addition to Dr. Du, the research team consists of Svetlana Sukhishvili, Hong-Liang Cui, Rainer Martini, Kurt Becker, and Christos Christodoulatos, all of Stevens, and Ryan Bise of OFS Laboratories. The research is supported by a $1.3 million NSF grant.