Expansion from conventional analytical methods to smart sensors: advances in detecting organic and inorganic pollutants

Various organic and inorganic pollutants have created harmful effects on the environment. These pollutants pose significant threats to ecosystems and human health owing to their high toxicity and persistence in the environment. The effects of these pollutants on environmental policy details need to be analysed. In the traditional method, several advanced analytical techniques, including GC, HPLC, AAS and ICP-MS, were used to detect pollutants, providing high sensitivity and accuracy for analysis. However, these techniques require trained personnel, sophisticated instrumentation, complex sample preparation and laboratory-based analysis, which limit the real-time and on-site monitoring. Their high operational cost and low throughput also restrict the widespread use in large-scale environmental surveillance. But the recent advances in sensor-based technologies offer promising alternatives to overcome these limitations, enabling rapid, portable, selective and cost-effective detection of environmental pollutants, especially those found in environmental water, drinking water and food, etc. In this review, we have described the basic pollutants and their detection limits, highlighting key sensor-based technologies such as electrochemical, optical, piezoelectric, thermal, acoustic and biosensors for the detection of toxic pollutants. Recent trends of using sensor-based devices and the addition of artificial intelligence (AI) and the Internet of Things (IoT) for the monitoring of pollutants indicate that sensor technology has been modified in recent years. The above-mentioned sensors are explained in terms of their cut-off values, LOD and LOQ. This review will provide valuable insights for the researchers who are working on environmental pollutants by highlighting the differences between conventional analytical techniques and sensor-based approaches.HIGHLIGHTSOrganic and inorganic environmental pollutants pose a serious risk to human health and ecological systems.Conventional techniques such as HPLC, GC and AAS are widely used for pollutant detection but need complex instruments and longer analysis time.The performance of analytical results declines because of a longer threshold when pollutants are present at very low concentrations.Fabrication of sensor-based technology to provide selective, cost-effective and a great LOD of environmental pollution.