The ability to accurately detect and quantify biomolecules like amino acids and peptides is fundamental to advancing our understanding of biological systems and developing new therapeutics. O-Phthalaldehyde (OPA) plays a central role in this endeavor by acting as a powerful fluorescent derivatization agent. Its chemical properties are key to its widespread use in analytical techniques, most notably in High-Performance Liquid Chromatography (HPLC).

The core of OPA's utility lies in its reaction with primary amines. When OPA encounters a primary amine, such as that found in amino acids or the N-terminus of peptides, it undergoes a condensation reaction. In the presence of a nucleophile, typically a thiol like 2-mercaptoethanol or 3-mercaptopropionic acid, a cyclic isoindole derivative is formed. This resulting molecule is highly fluorescent, with optimal excitation wavelengths around 340 nm and emission wavelengths around 455 nm. This fluorescence is the signal that analytical instruments detect and quantify.

The efficiency and specificity of this reaction make OPA an excellent choice for sensitive detection. When you buy O-Phthalaldehyde online, you are acquiring a reagent that enables the transformation of otherwise undetectable or weakly detectable molecules into brightly fluorescent compounds. This is particularly advantageous when analyzing biological samples where amino acid concentrations can be very low. The process of O-Phthalaldehyde HPLC derivatization is carefully optimized to ensure complete reaction and stable fluorescent products.

Ningbo Inno Pharmchem Co., Ltd. supplies O-Phthalaldehyde that is specifically produced to facilitate this reaction reliably. The high purity of their OPA ensures that the reaction proceeds cleanly, minimizing side products and maximizing the sensitivity of the detection method. Understanding the underlying chemistry of this OPA reagent for peptides and amino acids is crucial for researchers to effectively apply it in their studies and achieve precise quantitative results.