International group is developing new technology that uses optical glass fibers for diagnostic purposes.
Collaborating research groups including Carleton University (Ottawa, Canada), Université de Mons (Mons, Belgium) and Jinan University (Guangzhou, China) are developing a new lab-on-fiber method that uses optical glass fibers as platforms for chemical sensors to monitor biomarkers.
The team coat the fibers with a thin layer of metal and then with aptamers that can detect different target molecules. A micro light source connected to the end of the fiber guides the light to the probe. Light is detected and analyzed using a spectrometer. The detection site is located in a short segment of a fiber’s outer surface.
Typically, in lab-on-chip technologies, analytes from a biological sample, such as a drop of blood, react with chemicals on the chip that then induce voltage changes or vary the current flowing through a conductor. However, among the downsides of current lab-on-chip technologies are the relatively large size for use in vivo, corrosion of metal sensors and toxicity to humans. Developing instruments that combine low cost and portability with efficiency and reliability has been an ongoing challenge for scientists for many decades. Due to their low cost, small diameter, but large information-carrying capacity, optical glass fibers could be ideal for developing novel diagnostic tools. Using optics would allow easy use in aqueous solutions and would mean that the probes are not affected by electromagnetic radiation or large ranges in temperatures.
This work could potentially lead to further developments in diagnostics. The groups’ long-term goal is to develop a lab-on-fiber that can be used in vivo to monitor biological changes in real time. A potential future application could be in cancer screening technologies as an alternative to biopsies. For example, a fiber probe could be inserted directly in a blood vessel using a hypodermic needle and detect the presence of metastatic cells. Among the future challenges is finding a strategy to harden the probe’s surface coating to allow long-term storage without losing its binding properties to target molecules.
Source: IEEE Spectrum. How We’re Shrinking Chemical Labs Onto Optical Fibers.