PH4604 Topics in Applied Physics:
Bioimaging and Sensing
Chin Zong Yang
U1340544E
Fiber Optic Biosensors
Abstract:
This paper studies the clinical use of fiber optic biosensors, its advantages over traditional means of detection and limitations of this new technology. An in-depth study of its history, how the technology works, and comparisons with older methods of bio-sensing will also be made.
Introduction:
A biosensor is a device or method that allows a certain specific biological material to be detected. Common forms of detection are Fluorescence techniques, Raman Scattering, Plasmon Resonance, Near-infrared Spectroscopy and diffuse reflectance spectroscopy. These detection methods each have distinct advantages and disadvantages, and can adapt to a variety of different applications for different situations. However, traditional methods of biosensing usually requires the molecule to be labeled with an analyte, which must be chemically bound the molecule that is to be detected, making such methods slow, cumbersome and sometimes even toxic to the body.
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Besides being used in biosensing, fiber optics has been used in various telecommunication and high-speed networks around the world, replacing or supplementing traditional copper wires. This is due to the rapid advancement of relatively new technologies from fiber optics: the laser and the low cost of fiber optics production. Fiber optic biosensors also have excellent light permeability, easy and cheap to manufacture, able to illuminate the target with light and also able to transmit the light that is emitted by the target after
Evers, D. J., B. Hendricks, G. Lucassen, and T. Ruers. "Optical Spectroscopy: Current Advances and Future Applications in Cancer Diagnostics and Therapy." NCBI. National Center for Biotechnology Information, 8 Mar. 2012. Web. 13 Sept. 2015.
AAS has contributed to the understanding of elements having different absorption emission spectra due to their difference in energy levels. In the absorption spectrum, the absorbed light are shown as black gaps. As the number of electrons increase, the number of spectral lines also increase. Hence, by measuring the absorption of light, the concentration of the element within a sample can be determined. By knowing the concentrations of an element, scientists are now aware that even the smallest amount can make a significant impact towards the biological system. Therefore, scientists have brainstormed ways to monitor the use of chemicals in the
An optical fiber (or optical fiber) is a flexible, transparent fiber made by drawing glass (silica) or plastic to a breadth somewhat thicker than that of a human hair. Optical fibers are utilized regularly as a way to transmit light between the two closures of the fiber and find wide utilization in fiber-optic communication, where they allow transmission over longer separations and at higher bandwidths (information rates) than wire links. Fibers are utilized rather than metal wires in light of the fact that signals go along them with lesser measures of loss; moreover, fibers are likewise resistant to electromagnetic impedance, an issue which metal wires experience the ill effects of excessively. Fibers are additionally utilized for
As part of his work, he succeeded in varying the color of the light emitted by GFP so that different proteins and multiple, simultaneous biological processes could be tracked using GFP. His work that provided a better understanding of the fluorescence properties of GFP and its’ application as a marker. (Ehrenberg, 2008) In 2008, Osamu Shimomura, Martin Chalfie, and Roger Tsien were awarded the Nobel Prize in Chemistry in 2008. This research and that conducted by other scientists transformed the ability of the scientific community to track cellular movements of diseases such as cancer by using GFP as an intracellular marker. Using a gene that carries instructions to make GFP, scientists can attach glow-in-the-dark tags to selected proteins, either in cells in lab dishes or inside living creatures, to track their expressions and localization. (MacLachlan, 2011).
That is, the use of sweat, saliva and other body exudates, by calculating the concentration of glucose and exudate glucose glucose concentration in the measurement of blood glucose. Among them, the United States Medtronic first launch of the FDA approved blood glucose real-time continuous monitoring system (CGM). The system consists of a disposable continuous blood glucose detection probe, a radio frequency transmitter, and a receiving display. The probe can be attached to the patient's abdomen with a small wire (the wire is extremely small, the penetration is extremely fast and painless), and the glucose concentration in the subcutaneous interstitial fluid is measured every 10 seconds for 3 consecutive days. Through the wireless means to the receiver, the receiver every 5 minutes for the average data processing, and then converted to blood glucose stored value. This method of information collected every day refers to the blood test method of 100 times. In addition, developed by the United States Spectrx blood glucose tester is the use of laser cuticle in the skin to open a row of pores (and no pain), and then by a special sensor to collect interstitial fluid and measurement of blood glucose analysis, the same wireless technology has also been applied to monitoring blood pressure and oxygen level in the blood and so on, it has received large amount of investments
The ratiometric method for the L-Arg and L-Asn biosensors was based on the ratio of the fluorescence intensities (FI565 & FI625) of the Arg-sensing membrane and the Asn-sensing membrane at an excitation wavelength of 460 nm (λex = 460 nm) and two emission wavelengths (λem= 565 & 625 nm) as follows:
Metabolic syndrome (MS) is the cluster of serious diseases, including diabetes and cardiovascular diseases. It is spreading exponentially and the total cost of MS management is increasing. The continuous monitoring of MS components is very important to improve MS management and diagnosis in patients. In routine clinical practices, serum blood is used to quantify the MS markers. The blood sampling is painful and it is a hinder to use it for continuous and real-time monitoring of glucose. Hence we selected saliva as a medium for the detection of MS components. Measuring saliva glucose is challenging for very low glucose concentration (75-100 µM) and interfering molecules in saliva. This project was design and aim to develop a non-invasive Quantum
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In the past decades lasers have become evidently important to society. Lasers are normally perceived as devices used by our hands or large boxes found in research laboratories. Another evolvement in science that has taken place is the use of fluorescent dyes. Fluorescent dyes have become a common use for research and diagnostics in order to identify specific cell and tissue types. The use of such a dye is to identify for example, various chemical substances such as proteins, tag cells and DNA and their concentration. The only problem with such dyes is only as few as 10 colours have the ability to be distinguished. These newly developed lasers formed by fat cells are a combination of solid styrene beads. The purpose for this evolution is to capture light that is taken from the cells which are views using a spectrometer and thus, analyze the spectrum. It serves a function of measuring refractive index change. Before this step forward the ability to tag cells stood at around a couple hundred cells. Fat cells already consist of lipid droplets and act as natural lasers as it is. They need nothing more than to be supplied with nontoxic fluorescent dye. This new laser technology can help us further understand the cellular process and further improve medical diagnosis and therapies. Considering the level of
This article discusses optogenetic inhibition, which is the use of light-activated ion pumps to enable transient activity suppression of genetically targeted neurons by pulses of light. The created silencer ‘Jaws’ results in red light-induced photocurrents three times those of earlier silencers. This red-shifted variant can help solve known issues associated with implants, as it is a non-invasive method. Similar to previously mentioned papers focusing optogenetic excitation, this article will be used to provide more information about ChR variants and provides the basic knowledge to understand neuronal silencing as it is used in studies regarding optogenetics and Parkinson’s disease.
First, γ-cyclodextrin and pyrene can sensing of steroid and terpenes. γ-cyclodextrin will bearing a pyrenyl chromophore anchored at lower rim which formed the self-inclusion dimer in 10% dimethyl sulfoxide (DMSO) aqueous solution which can exhibited excimer emission at 470nm. Self-inclusion dimer
In this experiment, the use of a glass cuvette was used in order to avoid any chemical or environmental interference from the surroundings. Furthermore such glass cuvettes can support large wavelengths during transmission of light beyond 320 nm since this is the excitation wavelength region. Riboflavin is excited at around 370 nm, therefore the wavelength range must be large in order to detect a proper response. Plastic cuvettes are however inadequate as the range of wavelengths supported for transmission of light is very limited (5, Upstone). The geometry of the instrument of the spectrophotofluorometer has a specific angle and position for the excitation source and the detector. The excitation polychromator emits ultra-violet radiation and light to the interested sample and the shape of the polychromator resembles a triangular prism in which the monochromator has been angled at a 90∘ position. The transducer would detect the irradiation excitation beam and transfers it through the emission polychromator. The emitted beam would then travel to the detector to allow for the response signal to appear for the sample on the computer system (416, Skoog). The position of the cuvette is essential as it enables for the consistent readings of the response signals, as any shift in the cuvette position can create variation in results due to the position of lighting and detection of molecular samples hitting at different angles. The process of fluorescence is quite sensitive than absorption due to having lower detection limits because of the fact that it can detect lone molecules in excited states that are irradiated by UV-light unless they come into contact with other molecules within
According to the World Health Organization, cancer is a leading cause of death worldwide, and has the most devastating economic impact of any cause of death in the world. One of the leading causes of cancer-related mortality is gastric cancer, and that is due to the low rate of its diagnosis in its’ early stages as unfortunately, even the methods available for early detection of gastric cancer such as tumor biomarkers, are not very sensitive or efficient. Therefore, this proposal aims at non-invasive early detection of gastric cancer by firstly separating the blood plasma proteins albumin and globulin from mice with gastric cancer and healthy mice using chromatography, then enhancing them with biologically synthesized silver nanoparticles, and finally performing spectral analysis using surface-enhanced Raman spectroscopy, which is expected to provide information-filled, unique signatures of the biochemical components of whole proteins and clear non-overlapping peaks and clusters where the gastric cancer group can be explicitly distinguished from the normal group with 100% diagnostic sensitivity and specificity.
To compare different kinds of optical RR based sensors, it is necessary to define some performance metrics. The suitability of optical sensors for a particular application will depend on their performance across number of sensor requirements. Some metrics such as sensitivity, and sensor cost, can be defined numerically (either by means of experimental or theoretical calculations). Other metrics such as portability is more subjective or simply comparable but can have a significant influence on the commercial success of the methods. In this section a number of metrics that are typically considered to determine the performance of SOI RR based bio-chemical sensors are briefly
Fiber Optic Sensor for bio-sensing is a device that is used for the detection of the analyte. This analyte has a function to join physicochemical detectors and the components that are biological. A sensitive biological element includes cell receptors, organelles, enzymes, tissues, antibodies, microorganisms and nucleic acids. This element that is sensitive biological is a kind of bio-mimetic or a biological material which binds with the analyte during the study. There is another way to create biological sensitive elements and that is biological engineering through which the biologically sensitive elements can be created. When biological element and other signal interact with each other it produces another signal which is called transducer.