1.1 Introduction
In today’s world, the ability to detect a broad range of compounds is essential. Many common chemicals and biological materials, when released into the environment or encountered in medical contexts, pose serious risks to human health, wildlife, and ecosystems. Whether accidental or deliberate, the release of hazardous substances—such as methyl isocyanate in Bhopal or arsenic contamination in Bangladesh—can have devastating consequences. While some chemicals are easily detectable, many others present hidden dangers when present in low concentrations, posing long-term environmental and health risks.
In addition to environmental concerns, the threat of chemical and biological terrorism is also a growing concern, as seen in the 1995 Tokyo subway sarin attack. Industrial or agricultural chemical use can lead to contamination of water supplies and food chains, presenting significant health risks if not detected early. Furthermore, the detection of medical markers, such as glucose in diabetes, is critical for effective healthcare monitoring. The need for precise and rapid detection techniques extends to various fields, including food safety, water quality, and agricultural practices, where contaminants and pathogens can have wide-reaching consequences.
The type of sample—whether biological (e.g., blood, urine, or saliva) or environmental (e.g., water, soil, air)—greatly influences the choice of analytical techniques. Depending on the sample, pre-treatment steps such as extraction, concentration, or filtration may be necessary to ensure accurate analysis.
1.2 Neurotoxins
Neurotoxins, particularly nerve gases, represent a category of highly toxic chemical warfare agents, often derived from organophosphorus compounds. These toxins inhibit acetylcholine esterase enzymes, causing severe respiratory problems, convulsions, and even death. Early detection of such substances is crucial, especially in environments where accidental or deliberate release could lead to catastrophic consequences. For instance, exposure to sarin at a concentration of 70 mg/m³ can be fatal in under a minute. Early detection systems are vital to preventing such rapid onset of health crises.
1.3 Pesticides
Pesticides are heavily used in modern agriculture to control insect infestations, but overuse and runoff can lead to significant environmental contamination. Organophosphate pesticides, in particular, pose health risks due to their neurotoxic properties. Even though these compounds degrade more quickly than older pesticides like DDT, they remain a serious threat to human health. Monitoring pesticides in environmental and food samples is crucial for maintaining public safety. Regulatory frameworks such as the European Union’s Water Framework Directive help limit pesticide levels in drinking water, but reliable, sensitive detection methods are still needed for widespread monitoring.
1.4 Drug Detection
The detection of drugs—whether pharmaceuticals in the environment or illicit substances—is of paramount importance. Pharmaceuticals, often excreted in unmodified or partially modified forms, are increasingly detected in water systems, with potential long-term effects on ecosystems and human health. The widespread use of antibiotics in agriculture has also raised concerns about the development of antibiotic-resistant bacteria.
Similarly, detecting illicit drugs in environments such as airports is typically performed using sniffer dogs, which can struggle in environments with competing odors. Emerging technologies like electronic noses, which can rapidly detect multiple compounds, are being developed to address these challenges. In medical settings, detecting drugs of abuse or pharmaceuticals in biological samples requires advanced analytical techniques like solid-phase extraction followed by chromatographic methods.
1.5 Microbial Contamination
Microbial contamination, whether in water, food, or healthcare environments, can have serious health consequences. Infections like MRSA or Salmonella, and the potential use of pathogens like Anthrax as biological weapons, present ongoing public health concerns. Traditional methods for microbial detection, such as growing cell cultures, are time-consuming and sometimes inadequate for identifying specific pathogens quickly. As a result, there is growing demand for rapid, point-of-care detection tools that can quickly identify specific pathogens in water or food samples. Such technologies would be invaluable for maintaining safety and preventing outbreaks.
1.6 Carcinogens
Carcinogens, which often do not show immediate effects on health, pose a long-term risk to human populations. These compounds, including certain industrial chemicals, food additives, and air pollutants, can accumulate in the environment and enter the food chain, resulting in elevated concentrations in higher organisms. Identifying and quantifying carcinogenic substances requires advanced analytical tools capable of detecting low concentrations in complex environmental and biological matrices. Portable, cost-effective sensor technologies would greatly enhance the ability to monitor and mitigate exposure to carcinogens, providing better long-term protection for public health.
Conclusion: The Need for Enhanced Analytical Methods
The increasing complexity of detecting hazardous substances in biological and environmental samples requires significant advances in analytical technologies. While traditional laboratory techniques like HPLC and mass spectrometry remain essential for detailed analysis, there is a growing demand for portable, cost-effective sensors that can operate in the field and provide rapid results. The development of advanced sensor technologies, such as biosensors and multi-sensor arrays, promises to revolutionize the way we monitor environmental contaminants, pathogens, and toxins, enabling more effective prevention and intervention strategies. As analytical methods evolve, it is crucial to address the growing need for accurate, accessible, and real-time detection tools that can protect human health, the environment, and public
