Biochemical Assays: Concept
Before delving into the diverse applications of biochemical assays, it is pertinent to understand the concept of biochemical analysis. Biochemical assays within the scope of biochemical analysis are in vitro analytical methods that enable researchers to study, detect, or quantify the binding interaction or activity of biomolecules. These assays are used to characterize the interactions between protein, DNA, and RNA molecules and serve as valuable tools for drug characterization.Â
Types of Biochemical Assays
Biochemical assays are routinely used in laboratories, and some of these include enzyme assays such as kinase assay, phosphatase assay, protease assay, in vitro poly (ADP-ribose) polymerases (PARP) assay; cancer cell panel and in vitro oncology assay; NAB assay (neutralizing antibody assay); amino acid metabolism assays such as branched-chain amino acid assay and monoamine oxidase assay; carbohydrate metabolism assays such as lactose assay, pyruvate assay, starch assay, glycogen assay, glutamate assay; and, ion and cofactor assays such as NAD/NADH assay and NADP+/NADPH assay. These assays can be of three major types, i.e., binding assay, functional assay, and transporter and nuclear hormone receptor (NHR) assays. These assays are developed for diverse targets and use different technologies. For example, functional assays can use spectrophotometric absorption, radioimmunoassay (RIA), homogeneous time-resolved fluorescence (HTRF), time-resolved fluorescence resonance energy transfer (TR-FRET), and other technologies. The binding assays, on the other hand, utilize filtration, surfactant-associated protein A (SPA), fluorescence polarization, and HTRF.
Applications of Biochemical Assays
Biochemical assays help to elucidate biochemistry by unraveling the binding and activity of biomolecules.Â
Among the different assays discussed, enzyme assays are the most frequently used in laboratories. Scalable enzyme assay kits are commercially available for studying the activity of an enzyme and its end products, along with the mechanistic pathways involved. These assays also help to study how a target compound can influence the activity of an enzyme and the mechanism of its action. Thus, enzyme assays can help to screen compounds, including drugs, for their enzyme-activation or enzyme-inhibition properties.
Metabolism assays are also frequently used in laboratories to quantify the activity of metabolites produced, the cellular processes involved in different metabolic reactions, and the mechanistic pathways involved.Â
As focus and efforts continue to increase in oncology research, biochemical assays have become indispensable tools. These assays can help to identify tumor biomarkers such as antigens, enzymes, or hormones, which in turn help to diagnose tumors and evaluate the prognosis of the disease. These assays also help in identifying potential targets for cancer treatment.
During an acute infection, a patient develops neutralizing antibodies that reduce the infectious capacity of the virus. These antibodies can be short-lived or persist for a lifetime, and quantified using a NAB assay. This high-throughput assay is helpful in COVID-19 diagnosis, identification of potential donor candidates for convalescent plasma therapy, and monitoring antibody levels post-vaccination.
In conclusion
Biochemical assays are sensitive and reliable techniques. They help to identify potential targets and gain insight into cellular processes such as cell signaling, metabolism, and cell apoptosis, along with mechanistic pathways. Biochemical assays have diverse applications, and like cell-based assays, they help in high-throughput screening and serve as an invaluable tool in drug discovery and development.