Environmental monitoring application demands

Application areas for affinity-based sensors and immunosensors are specific toxic compounds or class of toxins detection. The most developed and applied recognition layer is antibody based. As the commercial success of immunoassays becomes more evident in health care, food, and environmental monitoring the demand for faster techniques will be sufficient for continued affinity sensors development. 

The answer lies in microsystem design and fabrication, applied to a relatively simple arrangement of gas sensors (the higher the integration the better). Combined with microelectronics, it is perfectly suited for the mass production of EN modules. Microsystems are usually produced in batches and will meet demand at low cost. Additionally, small size, low energy consumption and long-term stability can be achieved. Of course, not only consumer applications will benefit from the microsystem approach, since the improvements are also relevant to instruments used in industrial applications, medical care or in environmental monitoring. 

The analysis of trace substances in environmental science, pharmaceutical and food industries is a challenge since many of these applications demand a continuous monitoring mode. The use of immunosensors based on AuNPs in these applications should also be appropriate. Although there are many recent developments in the immunosensor field, which have potential impacts [36], nevertheless there are few papers concerning environmental analysis with electrochemical detection based on AuNPs. The application of some developed clinical immunosensors can also be extended to the environmental field. 

Enzyme-based applications for environmental screening or monitoring demand tailored biocatalysts performing catalysis in non-natural substrates and/or in non-usual or hostile media. Moreover, the increased complexity of contaminated environmental sites also demands efiicient biodegradation of xenobiotic compounds through new and multiple engineered pathways where the tailored biocatalysts should perform in their host microbial cells [434]. 

The ability to control the interaction between a wide diversity of biomolecules with surfaces can be also exploited as an effective way to develop reagentless, sensitive, reusable, and real-time biosensors [51-56]. Such sophisticated biosensors are expected to impact a wide range of applications, from clinical diagnosis[57] and environmental monitoring [58] to forensic analysis [59]. Another significant potential application of dynamic surfaces is in bioseparation of proteins and other biomolecules for basic life science research, as well as industrial applications [60-63]. With the rapid development of recombinant proteins in the treatment of various human diseases, the dynamic surface-based bioseparation systems could meet the demand for more reliable and efficient protein purification methods [64]. Stimuli-responsive surfaces are also expected to play a crucial role in the search for more controllable and precise drug delivery systems [65]. 

Also consider the use of NIST sediments 1646, 2704, and soils 2709-2711 in exploration geochemistry. These samples were certified largely in view of the demand for samples to support monitoring of toxic elements in environmental samples. However, many of the elements certified overlap either the list of primary ore elements or the list of pathfinder elements. Thus, these samples may legitimately be used in a very different application than the one that prompted certification. The sample matrix is ideal for the alternative application, and so is the suite of certified elements. 

The continuous determination of compounds, which may adversely affect ecosystems and/or human health, is a major regulative and legislative goal of environmental protection nowadays. Considering the costs and efforts related to this task corroborates a clear demand for portable, real-time, in-situ, field applicable and cost-effective monitoring techniques. Due to their inherent properties, vibrational spectroscopic sensors, in particular fibre-optic sensors show a high potential to contribute to these applications. 

However, it should be mentioned that there is a flexible hand-held electrochemical instrument on the market, which can be programmed to be used in a variety of voltammetric/amperometric modes in the field [209]. Although the majority of biosensor applications described in this review were for single analyte detection, it is very likely that future directions will involve development of biosensor arrays for multi-analyte determinations. One example of this approach has been described in an earlier section, where five OPs could be monitored with an array of biosensors based on mutant forms of AChE from D. melanogaster [187]. This array has considerable potential for monitoring the quality of food, such as wheat and fruit. Developments and applications of biosensors in the area of food analysis are expected to grow as consumer demand for improved quality and safety increases. Another area where biosensor developments are likely to increase significantly is in the field of environmental analysis, particularly with respect to the defence of public... 

A multidisciplinary effort is required to design and build instruments with previously unavailable capabilities for demanding new applications. Instruments with more sensitivity are required today to analyze ultra-trace levels of environmental pollutants, pathogens in water, and low vapor pressure energetic materials in air. Sensor systems with faster response times are desired to monitor transient in-vivo events and bedside patients. More selective instruments are sought to analyze... 

The current research focus within the sensor development field seems to be concentrated on miniaturization while incorporating multiple quantitative analytical capabilities. Other high-demand characteristics are shorter response time, minimal hardware requirements, multiple analyte and media capabilities, and improved sensitivity, selectivity, and specificity (Zemel 1990). Advancements and improvements for both biological and chemical threat agent sensors will have numerous other benefits to diverse applications, such as quality and process control, biomedical analysis, medical diagnostics, fragrance analysis, environmental pollution monitoring, and control forensics. 

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