Grand Challenges in Analytical Science

Analytical science is related to the development and application of techniques for detection of analytes, characterization of composites, analysis of samples, and monitoring of chemical and biochemical systems. It has played significant roles in the studies of physical, life, material, environmental, food, medical, and sustainability sciences. In the recent years, we have witnessed various techniques for single-cell analysis, screening of circulating tumor cells, viral diagnostics, detection of radioactive substances and explosive compounds, screening and identification of abused drugs, tracking contaminants and chemicals to ensure water quality and food safety, the study of omics, and characterization of synthetic polymers and nanomaterials. For example, various analytical technique, such as reverse transcription polymerase chain reaction (RT-qPCR), loopmediated amplification (LAMP), and clustered regularly interspaced short palindromic repeats (CRISPR) assays have been applied for sensitive and specific detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes COVID-19 disease (Huang et al., 2020; Wang et al., 2021). LAMP is attractive because there is no need for temperature cycling and it provides extremely high sensitivity (down to fM) with fluorescent, electrochemical or electroluminescent signal transduction. To minimize the threat of pandemics, vaccines against pathogens such as Zika virus and SARS-CoV-2 have been developed. For quality control and safety of vaccines, many analytical techniques such as sampling, purification, high performance liquid chromatography (HPLC), and gene expression profiling are needed. To meet the requirement of various studies and needs of society, analytical techniques must be in general sensitive, selective, fast, accurate, and simple. The instruments must be cost effective, easy in operation and maintenance, compact (portable ideally), suitable for the analysis of various samples, and available to provide wide dynamic ranges for quantitation of analytes. Analytical techniques are chosen mainly based on the purpose of the study, equipment available, properties of the analyte, and nature of the sample. For example, optical techniques provide high temporal and spatial resolution are commonly applied for cell tracking. To improve reproducibility, efficiency, and accuracy of the cell studies, the sequential cell images are then subjected to computational object tracking to track cells events over time and to obtain signals from each object. When in-vivo monitoring of drug function is the aim, nonconstructive optical techniques allowing deep penetration from the surface is usually carried out. In this case, materials can absorb light and generate optical signals like fluorescence in the infrared (IR) or near IR (NIR) region are suitable. For environmental analysis and forensics, portable and low-cost on-field analytical instruments are ideal. To provide high specificity and sensitivity for quantitation of various analytes, nanomaterials with high electrochemical activity and conductivity have become more popular in developing electrochemical sensing systems (Wongkaew et al., 2019). Many nanomaterials based functional electrodes have shown their potential in various fields; for example, fuel cells, removal of contaminants from polluted water, and degradation of toxic chemicals in the air. Nano or micro devices have gained more attraction in biological analysis, with advantages of use of small sample volume, consumption of extremely low amounts of reagents and solvent, high resolution, and Edited and reviewed by: Elefteria Psillakis, Technical University of Crete, Greece