Fiber-optic environmental monitoring

Hirschfeld, T. Deaton, T. Milanovich, F. Klainer, S. Fitzsimmons, C. Project Summary—Feasibility of Using Fiber Optics for Monitoring Groundwater Contaminants U.S. Environmental Protection Agency, Environmental Monitoring Systems Lab. Las Vegas, NV, January 1984. 

Fiber-Optic Probes. Fiber-optic probes provide remote sampling capabilities to Raman instmmentation, are stable, and give reproducible signals. Their historical niche has been in environmental monitoring. More recently these probes have been used in chemical process control and related areas such as incoming materials inspection. 

The potential applications of NIR OFCD determination of metal ions are numerous. The detection of metal contaminants can be accomplished in real-time by using a portable fiber optical metal sensor (OFMD). Metal probe applications developed in the laboratory can be directly transferred to portable environmental applications with minimal effort. The response time of the NIR probe is comparable to its visible counterparts and is much faster than the traditional methods of metal analysis such as atomic absorption spectroscopy, polarography, and ion chromatography. With the use of OFMD results can be monitored on-site resulting in a significant reduction in labor cost and analysis time. 

Applications of fiber-optic pH sensors in environmental analysis, biomedical research, medical monitoring, and industrial process control have been reviewed by Lin [67]. A multitude of luminescent systems for pH monitoring are commercially available, mostly under special trademarks. Pyrene [68-70], coumarin, bromothymol blue [71] and fluorescein [72-74] derivatives are typical examples that have been used in research in the past two decades. Carboxyfluorescein derivatives have been directly applied to skin tissue samples for the lifetime imaging of pH gradients in the extracellular matrix of the epidermis [75]. Two-photon excitation microscopy became an estab-... 

Solid-phase microextraction (SPME) is a sampling and concentration technique used to increase the sensitivity of HS methods. This technique is utilized for arson analysis and environmental monitoring purposes and also for clinical and forensic procedures. Short, narrow diameter, fused-silica optical fibers coated with stationary phase polymers are either immersed in the sample or the HS and compounds are adsorbed or absorbed (depending on... 

Fiber-optic sensors are less expensive, more rugged, and smaller than electrodes in the future we may see the former replacing the latter in various areas of analytical and clinical chemistry. Fields of application include environmental monitoring, process control, remote spectroscopy in high-risk areas with radioactive, explosive, biological, or other hazards, titrimetry, and in-vivo bioanalysis. 

The recent analytical literature abounds with reports on the development of electrochemical, fiber optic, piezoelectric, and other sensors. Novel detection principles are frequently announced, and attainment of improved sensor quality in terms of selectivity, sensitivity, and lifetime are the goal of many established as well as newly formed research groups. The need for continuous monitoring of critical parameters in clinical chemistry, biotechnology, pharmaceutical, chemical, and nuclear industries, chemical warfare or environmental control is the driving force behind the sensor research. 

Optical fiber Dye/Polymer matrix Hydrocarbons Environmental monitoring PetroSense... 

Adaptation of a Fiber-Optic Biosensor for Use in Environmental Monitoring... 

---