Fiber Optic Equipment Goes Biocompatible and Implantable thanks to Hydrogel Fibers

FBGs used in hydrogel fibersA biocompatible and highly stretchable optical fiber made from hydrogel may be implanted in the body to deliver therapeutic pulses of light or light up at the first sign of disease. This hydrogel fiber was developed by researchers from MIT (Massachusetts Institute of Technology) and Harvard Medical School. Hydrogels have already shown significant potential in everything from wound dressings to soft robots, but until now their fiber optic applications have been limited from their lack of toughness. Hydrogels are made of hydrophilic polymer chains that absorb up to 90 percent water. Such fiber optic products aren’t very strong or durable, but by adding glass tiny fibers the researchers created a tough, bendable, stretchable material.

In other words, a hydrogel is an extremely absorbent type of gel, a network of simple polymers that can contain up to 99,9% water, by weight. As the walls of this hydrogel, the material lining the interior of an optical fiber is clear but tuned to produce a phenomenon called total internal reflection. This means that light that moves at certain angles from the cable’s core material to its lining will be entirely reflected. By tuning hydrogel to create the same effect, scientists and engineers from MIT created a form of biocompatible optical cable. Getting light into the body is important: in the most basic sense, pulses of light are information, and having a hard-wired line of communication to implanted technology will be essential for development. However, it should be noted, such a wireless technique is still too unreliable for most people to bet their lives on, and it’s also notoriously hard on power consumption.

The researchers say that fiber optic products may serve as a long-lasting implant that would bend and twist with the body without breaking down. The researchers also have devised multiple recipes for making tough but pliable hydrogels out of various biopolymers. Plus the team has come up with ways to bend hydrogels with various surfaces such as metallic sensors and LEDs. Each optical fiber transmitted light without significant attention or fading. These fiber optic devices also found that fibers could be stretched over seven times their original length without breaking. Such modern fiber optic products can be used for long-term diagnostics, to optically monitor tumors or inflammation.

In other words, hydrogel fibers are interesting and provide a compelling direction for embedding light within the human body. Only considerable efforts in optimizing and managing the physical and mechanical properties of fibers will enable practical applications of medical relevance.

Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line: fiber Bragg grating sensors, FBG interrogators, and multiplexers, Distributed Temperature Sensing (DTS) systems. We create and supply a broad variety of top-notch fiber optic solutions for the monitoring of various facilities all over the world.

If you are interested in Optromix fiber optic products, please contact us at info@optromix.com

How to Make Surgery Less Invasive with the Fiber Optic Products Help?

FBGs for less invasive surgeryOptical fibers have the potential to be used in many biomedical applications. Such fibers have been used in medical devices since the 1960s when fiber optic bundles were successfully pioneered for both illumination and imaging through endoscopes. Optical fiber imaging tools were widely accepted for invasive surgery since the 1980s. The minimally invasive surgery promises decreased pain and trauma during operations, faster recovery, and a reduced risk of infection. Nowadays special fiber optic products also are used as intelligent sensors to monitor physiology parameters such as temperature, pressure, oxygen concentration, and applied force.

Fiber optic sensors offer many advantages in comparison with conventional electronic sensors in medical sensing: small size, immunity to electromagnetic interference (EMI), enhanced sensitivity, robustness, and geometrical versatility. Additionally, they are free from electrical parts or conductors in the sensor area. The unique properties of fiber optic products and based on the fiber optic equipment have enabled complicated procedures in cardiovascular examiners, angiology, gastroenterology, ophthalmology, oncology. neurology. dermatology, and dentistry. Novel specialty fiber types are also opening up entirely new sensing concepts. In addition to this, endoscopes represent the largest end-use market for medical fiber optics, supported by the growing popularity of minimally invasive surgeries. Minimization of medical instruments is a key trend encouraging the use of small and efficient optical fibers.

The integration of fiber optic applications in medical devices is a difficult task because it involves solving such problems as design and selection of fiber, packaging material, cost-effective manufacturing, quality control, and traceable record keeping.

In the last two decades, a variety of fiber optic products have been developed. However, it should be noted, point sensors based on Fabry-Perot interferometers and fiber Bragg gratings (FBGs) are probably the most deployed sensors in medical applications.

Fiber optic products and based on the fiber optic sensors are safe, valuable, highly stable, biocompatible tools for health-monitoring systems and they are amenable to sterilization and autoclaving. By modifying properties such as numerical aperture, core and cladding diameters, and coating material, the fibers can be adapted to different applications.

Why do fiber optic products find so many biomedical uses? Firstly, optical fibers, which used in medical sensors, have a thin polyimide coating to provide a small section and suitability for different kinds of sterilization processes. The temperature resistance of polyimide is difficult to match with other polymer materials. Secondly, the highly desirable parameter of the optical fiber for invasive surgery is tolerance to tight bonds. This allows for movement of the catheter, which winds through veins and arteries, and around organs and bones, on its way to an application area.

Summing up all of the above, the biomedical sensing market represents a lucrative and growing opportunity for fiber optic sensors, particularly for large volumes of disposable probes. The demand for move patient monitoring devices combines with a trend toward minimally invasive surgery, which itself requires a variety of small size that can be incorporated into catheters and endoscopes. There is also an opportunity for fiber optic sensors as EMI-compatible sensors to monitor vital signs during the use of MRI (and related techniques), as well as RF treatments.

Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line: fiber Bragg grating sensors, FBG interrogators, and multiplexers, Distributed Temperature Sensing (DTS) systems. We create and supply a broad variety of top-notch fiber optic solutions for the monitoring of various facilities all over the world.

If you are interested in Optromix FBG sensors or other fiber optic products, please contact us at info@optromix.com

 

Monitoring loadbearing structures of large scale public facilities with fiber optic sensors

There are plenty of different fiber optic applications of FBG sensors; it can monitor a variety of structures, buildings, and other facilities. This technology is often used in construction work and to track different parameters in industrial production and other areas.

Fiber optic applications include effective monitoring of loadbearing structures in different public facilities. Most of the modern construction sites are technically sophisticated and uniquely designed. In the process of project development, certain safety measures are planned, however, it may change in time after the building utilization has started. Regular monitoring becomes crucial in this context and it may prevent different accidents. The automated monitoring fiber optic system allows tracking the technical condition of the object in real-time with minimal human involvement.

Fiber optic Bragg gratings (FBGs) are used as a sensing element in this monitoring fiber optic system. This kind of sensors doesn’t have electronic components and it makes them resistant to electromagnetic waves and fire safe. Fiber optic Bragg gratings are inscribed in the fiber with a UV laser. FBG in each sensor reflects the specific fiber optic wavelength with a spectrum width of approximately 1 nm. The grating is affected by mechanical and temperature impact and its physical change cause the shift in the fiber optic wavelength of the reflected light. The fiber optic wavelength shift is measured, which allows measuring the deformation and temperature change. Two gratings are used simultaneously to separate these parameters, where one of them is isolated from the mechanical impact. This allows tracking the temperature impact on the second grating and measuring the deformation. One optic fiber may have multiple gratings, each one of them provides a response at its own length, and the distance between gratings vary from 10 mm to several kilometers.

One of the most common methods to investigate sensors is to scan the FBG aggregate with a tunable source. The tunability range is usually around 100 nm (1500 – 1600 nm), the investigation frequency is from 1 to 500 Hz, and the number of parallel channels can be up to 8 channels.

Usually, it is enough to interrogate sensors once per 6 hours, when they are installed on a large public facility. Each sensor has 2 critical measurement levels (yellow and red), when this level is reached the optic fiber system sends out an alarm signal. The frequency of interrogation increases to 1 time per 30 minutes. Moreover, the notifications are sent out in case of malfunctioning. The software allows viewing the data collected from all the sensors as the graphs of relative deformation and temperature.

This fiber optic application of FBG sensors works perfectly well for large constructions, such as stadiums.