{"id":48502,"date":"2021-08-25T14:30:00","date_gmt":"2021-08-25T14:30:00","guid":{"rendered":"https:\/\/discover.restek.com\/uncategorized\/chiral-separation-2-optimization-of-chiral-separations\/"},"modified":"2026-01-28T17:32:06","modified_gmt":"2026-01-28T17:32:06","slug":"chiral-separation-2-optimization-of-chiral-separations","status":"publish","type":"post","link":"https:\/\/discover.restek.com\/de\/blogs-ja\/gnbl4619\/chiral-separation-2-optimization-of-chiral-separations","title":{"rendered":"Chiral Separations 2: Optimization of Chiral Separations"},"content":{"rendered":"\n

The cyclodextrin columns are unique in their ability to resolve a variety of chiral compounds. In my last blog I discussed the individual column separations of various chiral compounds. Today, I\u2019d like to show how to optimize that separation. Variation in linear velocity and temperature ramp rate can greatly affect the resolution of enantiomers. Depending on the type of chiral column, initial GC oven temperature can affect peak width. Column sample capacity varies with different compounds, and overloading results in broad tailing peaks and reduced enantiomeric separation.<\/p>\n\n\n\n

Linear Velocity (Column Flow)<\/h2>\n\n\n\n

In our analysis, we worked with hydrogen. Hydrogen\u2019s optimal linear velocity is around 40 cm\/s. However, as shown in Figure 1, better resolutions were achieved with higher flows\/linear velocity (60-80 cm\/s).<\/p>\n\n\n\n

\"chart,<\/figure>\n\n\n\n

Figure 1: Resolution factors as function of linear velocity. Rt-\u03b2DEXsa<\/strong>: 40\u00b0C (80\u00b0C for lactones) to 200\u00b0C @ 2\u00b0C\/min. (hold 1 min.). Hydrogen carrier gas.<\/em><\/p>\n\n\n\n

Temperature Program<\/h2>\n\n\n\n

The chiral resolution can improve with decrease in the temperature ramp speed. The best temp programs are 1-2 \u00b0C\/min (Figure 2).<\/p>\n\n\n\n

\"decorative\"<\/figure>\n\n\n\n

Figure 2: Resolution factors as function of temperature ramp. Rt-\u03b2DEXsa<\/strong>: 40\u00b0C to 200\u00b0C (hold 1 min.). Linear velocity 80 cm\/s. Hydrogen carrier gas<\/em><\/p>\n\n\n\n

For optimal chiral separation use:<\/h2>\n\n\n\n
    \n
  • Faster linear velocities (60-80 cm\/sec.) with hydrogen carrier gas.<\/li>\n\n\n\n
  • Slower temperature ramp rates (1-2\u00b0C\/min.).<\/li>\n\n\n\n
  • Appropriate minimum operating temperature (40 or 60\u00b0C).<\/li>\n\n\n\n
  • On-column concentrations of 50ng or less.<\/li>\n<\/ul>\n\n\n\n
    <\/div>\n","protected":false},"excerpt":{"rendered":"

    The cyclodextrin columns are unique in their ability to resolve a variety of chiral compounds. In my last blog I discussed the individual column separations of various chiral compounds. Today, I’d like to show how to optimize that separation. Variation in linear velocity and temperature ramp rate can greatly affect the resolution of enantiomers. Depending on the type of chiral column, initial GC oven temperature can affect peak width. Column sample capacity varies with different compounds, and overloading results in broad tailing peaks and reduced enantiomeric separation.<\/p>\n","protected":false},"author":50,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kadence_starter_templates_imported_post":false,"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"footnotes":""},"categories":[794],"tags":[],"industries-application":[2263,2274],"post-badge":[],"resource-type":[],"product-library":[],"resource-technique":[2340],"ppma_author":[591],"class_list":["post-48502","post","type-post","status-publish","format-standard","hentry","category-blogs-ja","industries-application-cannabis-ja","industries-application-food-beverage-ja","resource-technique-gas-chromatography-gc-ja"],"acf":[],"taxonomy_info":{"category":[{"value":794,"label":"Blogs"}],"industries-application":[{"value":2263,"label":"\u30ab\u30f3\u30ca\u30d3\u30b9"},{"value":2274,"label":"\u98df\u54c1\uff5c\u98f2\u6599"}],"resource-technique":[{"value":2340,"label":"\u30ac\u30b9\u30af\u30ed\u30de\u30c8\u30b0\u30e9\u30d5\u30a3\u30fc"}]},"featured_image_src_large":false,"author_info":{"display_name":"Jana Hepner, PhD","author_link":"https:\/\/discover.restek.com\/de\/author\/jana-hepner-phd\/"},"comment_info":0,"category_info":[{"term_id":794,"name":"Blogs","slug":"blogs-ja","term_group":0,"term_taxonomy_id":794,"taxonomy":"category","description":"","parent":0,"count":438,"filter":"raw","cat_ID":794,"category_count":438,"category_description":"","cat_name":"Blogs","category_nicename":"blogs-ja","category_parent":0}],"tag_info":false,"authors":[{"term_id":591,"user_id":50,"is_guest":0,"slug":"jana-hepner-phd","display_name":"Jana Hepner, PhD","avatar_url":{"url":"https:\/\/discover.restek.com\/wp-content\/uploads\/people-hepner-jana.jpg","url2x":"https:\/\/discover.restek.com\/wp-content\/uploads\/people-hepner-jana.jpg"},"0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts\/48502","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/users\/50"}],"replies":[{"embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/comments?post=48502"}],"version-history":[{"count":4,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts\/48502\/revisions"}],"predecessor-version":[{"id":85620,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts\/48502\/revisions\/85620"}],"wp:attachment":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/media?parent=48502"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/categories?post=48502"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/tags?post=48502"},{"taxonomy":"industries-application","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/industries-application?post=48502"},{"taxonomy":"post-badge","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/post-badge?post=48502"},{"taxonomy":"resource-type","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/resource-type?post=48502"},{"taxonomy":"product-library","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/product-library?post=48502"},{"taxonomy":"resource-technique","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/resource-technique?post=48502"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/ppma_author?post=48502"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}