Liquid Chromatography Separation And Purification Of Iodine Sea Alcohol Technology Was Studied

In recent years, with the rapid development of high-end technology, the development of pharmaceutical industry closely related to human survival is rapid. As a clinical injection, Contrast medium is a kind of chemical products which is injected intravenously into the human tissue (or organ), in order to strengthen the observation effect injection to.The development of contrast medium is from the first generation of ionic to the second generation of nonionic contrast medium, and iohexol is one of the representative of the second generation of nonionic contrast medium, Nonionic contrast medium were gradually replaced the ionic contrast medium due to their low permeability, stable chemical property and good human tolerance, and nonionic contrast medium can reduce the side effect for human bodies. However, the clinical use of each drug is related to the provisions, higher purity for iohexol injection is requested in pharmacopoeia, and total content of impurities is less than or equal to1%. The purification methods of iohexol include crystallization, recrystallization, chromatography and nanofiltration, However, these methods have their own shortcomings. As a result, the mass production in the industry is limited. Therefore, the study of purification process with a low cost for iohexol has the very important significance.The adsorption resin is a kind of chemical synthesized high molecular polymers. The resin is mainly used for the separation and purification of various mixtures based on adsorption and desorption characteristics. At the present study, the four kinds of resins, the macroporous resin XAD1600and SP207, ion exchange resin DOWEX50W*4and IRA67were chosen to purify iohexol. The purity of iohexol with macroporous resin was equal or greater than99%, and yield is about68%; The results showed that XAD1600was the best resin for purifying iohexol; The purity of SP207resin was the best, but its yield is only50%; The effects of ion exchange resin DOWEX50W*4and IRA67were poorer.Based on the above results, purification of iohexol with the tandem resins was further studied. Non-polar resin XAD1600and weak polarity resin XAD7HP were chosen as the tandem resins for purifying the iohexol. Purification effects of iohexol at the different volume ratios of36.6:0,32.7:3.9,29.9:6.7of XAD1600and XAD7HP were compared. The results showed that the optimum ratio was29.9:6.7based on the purification effect. At this ratio, the purity of iohexol was equal or greater than99%and yield is about90%. Contrasting to the single resin tandem resins improved the total yield of produce although the purify was slightly reduced to.Iohexol is a polyhydroxyl containing macromolecular compound with the stronger hydrophilic effect. Based on hydrophilic effect principle, analysis and detection for iohexol by cation ion chromatographic column with the strong acid property was established. This method avoids baseline instability due to the double pump in reversed phase-high performance liquid chromatography (RP-HPLC). At the same time, the detection time was shorten relatively. The established method of hydrophilic interaction chromatography provided a new research idea for purifying and preparing iohexol.