What You Need to Know about Biochemical Assays?

Posted by Maria Brown on July 30th, 2019

Biochemical assays are analytical tools created for in vitro applications. They are used to detect, quantify and/or study the binding or activity of a biological molecule. These can either include small molecules such as GSH or NAD and even macromolecules such as proteins. In essence, biochemical assays are similar in nature to or have an overlap with processes such as chemical analysis and titration. 

It is a fairly routine procedure that enables chemists to characterize targets and even understand their biomolecular functions. There are practically hundreds of possible biochemical assays, segregated on the basis of qualitative or quantitative assessing, depending on the biochemical process pathway that is to be explored. Biochemical assays can be used to understand the activity of certain functional biomolecules, such as enzymes.

Biochemical assay primarily contain two parts as follows:

• Part One: A substrate-specific probe which has the capability to identify the target of interest. In a usual scenario, this is either an antibody or a small molecular chelator.

• Part Two: A detection system which has the ability to turn the probe into a quantifiable signal. While these can be of different types, one of the most popular ones is horseradish peroxidase (HRP) which is used along with an oxidizing agent such as ADHP.

If we dig deeper, there are different types of biochemical detection systems too. They primarily fall into three categories:

• Fluorometric assays: These are assays that emit signals only upon excitation by a light source.

• Fluorogenic assays: These emit light similar to that of fluorometric assays.

• Luminescent Assays: These assays emit light only by way of a chemical reaction.

The applications of biochemical assays are far-reaching. They are used in processes such as ELISA assay, western blotting, and other immunohistochemistry assays. Protein expression and purification is usually the first step in the process while using biochemical assays.

Various types of scalable enzyme activity assays and binding assays include the following:

• Kinase: In this process, Kinase enzymes catalyze the transfer of a phosphate group onto a substrate from a donor group. Substates that are used here include proteins, lipids, carbohydrates, and nucleic acids.

• Methyltransferase: DNA methyltransferases are an enzyme family that can catalyze the methylation of DNA, thus having a significant effect on the DNA. The development of DNA MTase activity assays is reviewed with dedicated emphasis on assay mechanism and performance.

• Protease: This is used as a standardized assay to determine the activity of proteases for quality control. In this process, casein is used as a substrate and a blue colored chromophore is produced, which is essentially quantifiable.

• Radiolabel Binding: This type of assay is primarily used to determine the anatomical distribution of receptors and characterize them. The analysis process measures the affinity of the labeled ligand for a receptor.

Other types of assays that we can undertake include HDAC/HAT, Demethylase, PDE, Phosphatase, DUB, Nuclear Hormone, Ion Channels, and many more.

Also Read- NebioLab Drug Development Techniques: ADME Pharmacokinetics