Preparation And Chiral Resolution Of A Novel High Performance Liquid Chromatography Stationary Phase

Since the invention of chromatography by Russian scientist Tsevit,chromatographic separation technology has been widely used and has many branches,among which high performance liquid chromatography has shown its unique advantages in the separation of racemates.Cellulose and amylose derivatives,as chiral immobilization,have always been the focus of chiral separation investigator,among which cellulose and starch phenylcarbamate are the polysaccharide derivatives with the best separation effect and can resolute the most enantiomers.Other than widely known polysaccharides chiral stationary phase,polysaccharides such as chitin and chitosan are also used as chiral materials and show certain chiral separation ability.It broadens the field of chiral materials and lays a theoretical and experimental foundation for the subsequent search for other chiral materials by exploit other polysaccharides.Konjac glucomannan(KGM),as a natural polysaccharide,has shown its unique excellent function in medicine,food and other aspects,but as a chiral stationary phase,it is rarely reported.KGM has good water solubility compared with polysaccharides such as cellulose and amylose.It is composed of glucose and mannose linked by β-1.4 glycosidic bond,and each glucose and mannose has three chiral carbon atoms,which creates a chiral atmosphere for discerning chiral compounds.In a word,KGM is a latent chiral separation material.In this paper,a series of coated konjac glucomannan chiral stationary phases(CSP)were synthesized by chemical modification stemming from KGM,and their chiral separation performance was tested.The possibility of it as a potential chiral separation material was verified.Carboxyethyl konjac glucomannan(AMKGM)was synthesized with acrylamide as etherifying agent under alkaline conditions.It was coated on the surface of 3-aminopropyl silanized silica gel to prepare carboxymethyl konjac glucomannan stationary phase.It was characterized by Fourier transform infrared spectrometer(FTIR),X-ray Diffraction(XRD)and Thermogravimetry(TG).utilizing n-hexane/isopropanol as mobile phase,its separation ability of 10 chiral drugs was tested,and it was found that 7 chiral compounds were separated.Baseline separation of two chiral compounds was obtained,and the separation ability of 12 amino acid enantiomers was tested with methanol as mobile phase,and it was found that 8amino acid enantiomers were separated.Cyanoethyl konjac glucomannan(ANKGM)was synthesized with acrylonitrile as etherifying agent under alkaline conditions.It was coated on the surface of 3-aminopropylsilylated silica gel to prepare cyanoethyl konjac glucomannan.It was characterized by Fourier transform infrared spectrometer(FTIR),X-ray Diffraction(XRD)and Thermogravimetry(TG).its resolution ability was tested with 10 chiral compounds using n-hexane/isopropanol as mobile phase.It was found that four chiral compounds were separated,and two chiral compounds were separated at baseline.Hydroxyethyl konjac glucomannan(EOKGM)was synthesized with ethylene oxide as etherifying agent under alkaline conditions.It was coated on the surface of3-aminopropylsilylated silica gel to prepare hydroxyethyl konjac glucomannan.It was characterized by Fourier transform infrared spectrometer(FTIR),X-ray Diffraction(XRD)and Thermogravimetry(TG).With n-hexane/isopropanol as the mobile phase,its resolution ability was tested with 10 chiral compounds.It was found that four chiral compounds were separated,and two chiral compounds were separated at baseline.Hydroxypropyl konjac glucomannan(POKGM)was synthesized with propylene oxide as etherifying agent under alkaline conditions.It was glazed on the surface of3-aminopropylsilylated silica gel to prepare hydroxypropyl konjac glucomannan chiral stationary phase.It was characterized by Fourier transform infrared spectrometer(FTIR),X-ray Diffraction(XRD)and Thermogravimetry(TG)and its resolution was tested with 10 chiral compounds using n-hexane/isopropanol as mobile phase.Results demonstrated four of chiral compounds were separated,and two chiral compounds were separated at baseline.Using n-hexane/isopropanol as mobile phase,the resolution ability of rosin-based chromatographic column for 10 chiral compounds was tested.The upshots showed that it had resolution effect on 3 chiral compounds.Using methanol as mobile phase,the resolution ability of rosin-based chromatographic column for 12 amino acid enantiomers was tested.Results showed it was effective in resolving 4amino acids,and 3 amino acid enantiomers were separated at baseline.