Plants must be capable of responding to climatic fluctuations, diurnal rhythms, available supplies of water and nutrients, and insect attacks and infestations. To ensure such responses, plants need a network of regulating substances called phytohormones. These substances enable plants to respond to both biotic and abiotic stresses by initiating a cascade of orchestrated actions, and to trigger development-specific processes. In this article, we will discuss a highly sensitive analytical method for quantitative determination of phytohormones. The main representatives of the plant hormones are jasmonic acid (JA), cytokines, auxins, abscisic acid, salicylic acid, gibberellins, and strigolactones.
Tag: <span>HPLC</span>
Cation exchange chromatography (CEX) is a versatile method for separation of proteins based on exploiting differences in positive electrostatic charges. In CEX, proteins are bound to the negatively charged stationary phase (cation exchangers) and then eluted using a salt gradient. Typically, the liquid-phase pH in CEX is lower than the isoelectric points (pI) of the proteins. CEX has been used to monitor various post-translational modifications such as glycosylation, deamidation, phosphorylation, truncation, oxidation, C-terminal and N-terminal clipping, and N-terminal cyclization. Some of these variants may exhibit different bioactivity. Therefore, it is important to characterize protein variants and monitor the stability of these variants throughout the process of drug discovery, development, and manufacture. Characterization of complex proteins such as antibodies, has traditionally been performed using slab gel-based techniques such as isoelectric focusing (IEF). This technique is qualitative and time consuming. It also generates large quantities of chemical waste from the staining process…