MANUFACTURING
Chiral Chromatography in Pharmaceutical Analysis Advances and applications This article mainly focuses on the recent advances and applications of Chiral HPLC, LC-MS and SFC applications in Pharmaceutical Analysis. M V Narendra Kumar Talluri, Head, Dept of Pharmaceutical Analysis, NIPER
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olysaccharide derivatives are extensively used in chiral stationary phases. They provide multiple advantages including broad enantioselectivity, better resolution ability, easy availability, and high loadability under preparative separation conditions. Commercially available chiral stationary phases (CSPs) of this type are usually coated onto a silica matrix (or) covalently bonded to the silica matrix (immobilized). However, coated CSPs swell or dissolve and finally destroy the enantioselective capacity of the phase with some forbidden organic modifiers. The use of forbidden organic modifiers, such as chloroform, dichloromethane, acetone, ethyl acetate and tetrahydrofuran, in the mobile phase is, therefore, prohibited. To overcome these limitations, new immobilised CSPs were developed, containing polysaccharide derivatives covalently bonded to the silica matrix.
Coated vs Immobilised Chiral Stationary Phases (CSPs)
At present, nine immobilised polysaccharide-based CSPs are commercially available Chiralpak IA, IB, IC, ID, IE, IF, IG, IH, IJ. The chemical structures of these selectors are given in the below figure. Different approaches were reported to fix the chiral selector chemically linking the polysaccharide derivatives to the silica matrix, which is considered to be a prerequisite for enantioselective recognition. Consequently, the enantioselective recognition abilities of polysaccharide CSPs may be different. The immobilised CSPs are robust and can be used with a broader variety of solvents, as mentioned above. This extends the application range of these selectors in terms of enantioselectivity, but also in terms of mobile-phase solubility of compounds, offering benefits at both analytical and preparative scales. 50
P H A RM A F O C U S A S I A
ISSUE 44 - 2021
