Promote chiral method development with UPC2/MS technology

purpose

Using Waters (Waters®) ACQUITY UPC ² â„¢ system, MS detector may facilitate the development of methods of chirality.

background

Because of the potentially different biological/pharmacological/toxicological properties between enantiomers, chirality plays a crucial role in drug properties. Chiral analysis is usually performed early in the development of the drug. With its superior separation capability and high speed performance, SFC now has a place in the field of chiral analysis. In addition, SFCs can also reduce the use of toxic solvents, which are often associated with normal phase LC chiral analysis, such as n-hexane and chloroform. Analysts often encounter many structurally distinct stereoisomers that vary in purity from 70% to 90%. Therefore, shortening the chiral method development cycle has become an important measure to improve production efficiency. To this end, UPC ² TM/MS technology is now proposed to exploit the specificity of MS detection to facilitate the development of chiral methods. Although MS detection does not allow selective separation between enantiomers, it is possible to completely separate the different enantiomers and their impurities.

The Waters ACQUITY UPC ² /MS system is ideal for laboratories chasing high-throughput enantioselective analysis, enantiomeric excess determination of complex mixtures or matrices, and impurity map analysis .

solution

Two chiral sulfoxide compounds, oxfendazole and pantoprazole mixtures (each compound concentration of 0.2 mg/mL in methanol) were analyzed. The main experimental parameters are shown in Table 1.

In general, the development of chiral SFC methods involves the use of multiple columns and mobile phases for sample screening using similar gradients as described in Table 1. Parallel methods are used to increase throughput while multiple columns are used for sample screening (LCGCEurope, Application Book, Dec. 2009, 24-25). Alternatively, as shown in the present technical brief, multiple samples are simultaneously screened by SFC/MS, and then the enantiomers are distinguished by detection of extracted ion chromatography (XICs) (Chromatography A, 1003 (2003), 157). -166).

Figure 1. Structure diagram of oxfendazole and pantoprazole. The UPC2 chromatogram of the enantiomer of each chiral compound is shown in Figure 2. Baseline separation was achieved for both enantiomers, indicating that the IC column and methanol are suitable stationary phases and cosolvents, respectively. Compounds can be easily identified from extracted ion chromatography (XIC) by means of previously known molecular weights. The retention times of both compounds can be subsequently used for further optimization of the method. In this example, the throughput is doubled compared to the traditional SFC-UV method, where a single set of chromatographic conditions can only screen one compound.

to sum up

It has been demonstrated that the use of MS detection can facilitate the development of methods for chiral UPC ² . Two enantiomeric mixtures of different molecular weights can be simultaneously screened out by using the specificity detected by MS. Compounds can be readily identified by extractive ion chromatography (XICs) detection combined with previously known compound masses. As a result, the throughput of chiral method development has been doubled compared to the traditional SFC-UV method. The ACQUITY UPC ² /MS system is ideal for laboratories chasing high-throughput enantioselective analysis, enantiomeric excess determination of complex mixtures or matrices, and impurity map analysis.