Creative Biolabs has established a platform to analyze the therapeutic drug candidates with a series of liquid chromatography patterns, strictly following the ICH Topic Q6b guideline. Chromatographic patterns and data on identity, homogeneity, and purity can be achieved by affinity chromatography, reverse-phase liquid chromatography, ion-exchange liquid chromatography, size-exclusion chromatography, or other appropriate techniques.
Liquid chromatography (LC) utilizes a solid stationary phase to separate protein molecules in a liquid mobile phase. Liquid chromatography can serve as analytical or preparative applications. In column liquid chromatography, as the liquid mobile phase passes through the column, components in the mobile phase bind to the solid stationary phase in varying degree, also called chromatography media or resin. Protein molecules of interest in the mobile phase are separated from unwanted molecules, based on their different physicochemical interactions between the stationary and mobile phases. These binding interactions can be built on hydrophobicity (hydrophobic interaction chromatography, HIC), charge (ion exchange chromatography, IEC), specific binding interactions (affinity chromatography, AC), molecular size (size exclusion chromatography, SEC), or a combination of these techniques.
Each protein molecule elutes from the column in a specific order based on the differing strengths of its binding interaction with the resin and the mobile phase. When the mobile phase flows through the column, the column eluate is normally collected in separate fractions with monitoring the concentrations of the protein eluted from the column to form an elution curve, so called chromatogram, by a UV detector or spectrophotometer to measure light absorption at 280 nm (A280) of the amino acid tryptophan inner the protein. The resulting chromatogram can be utilized to quantify proteins in the eluate. Each distinct peak with high resolution represents a unique protein eluted from the column, and the area under the curve determines the amount of the corresponding protein. In many cases, a single peak may contain more than one protein species. Hence it is needed to deeply analyze the eluted fractions by other techniques, like gel electrophoresis. Creative Biolabs provide you all these described protein preparation procedures in order to obtain highly purified proteins for all cases usage. All the proteins are characterized in house in 4-6 weeks.