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SUPELCO Astec CHIRALDEX G-DP手性气相色谱柱 毛细管柱

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SUPELCO Astec CHIRALDEX G-DP手性气相色谱柱 毛细管柱
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SUPELCO Astec CHIRALDEX G-DP手性气相色谱柱 毛细管柱
 

  • CD Type: γ (gamma)
  • Derivative: Dipropionyl
  • Temp. Limits: -10 °C to 200 °C (isothermal) or 220 °C (programmed)
    Incorporates a phase consisting of a 2,3-di-O-propionyl-6-t-butyl silyl derivative of γ-cyclodextrin. This phase exhibits good hydrolytic stability, broad chiral selectivity, and are excellent for aliphatic and aromatic amines. It is also good for many aliphatic and some aromatic esters as well as exhibiting high efficiency and resolution at low retention times for polar racemates.

Features: 

  • Broad chiral selectivity
  • Good hydrolytic stability
  • Thermal limit 200/220 °C
  • Excellent for aromatic and aliphatic amines
  • Good for many aliphatic and some aromatic esters
  • High efficiency and resolution at low retention times for polar racemates

Mechanism Observations:

  • Mostly surface interactions
  • Fused ring structures better selectivity on gamma
  • Acids have better selectivity as methyl rather than ethyl esters

Size Selectivity:

    Both speed and sample capacity indicate a surface type mechanism for very polar racemates. Large bulky molecules still require a larger surface area than beta provides, therefore, an increase in selectivity is seen on the gamma derivative for fused ring structures. The smaller alpha cavity offered no selectivity while the beta covered the largest range of molecular sizes but the choice between beta and gamma is compound dependent for this phase. 

SUPELCO Astec CHIRALDEX G-DP手性气相色谱柱 毛细管柱 定货图片信息：

Product #Description
78033ASTAstec CHIRALDEX G-DP 毛细管气相色谱柱 L × I.D. 30m × 0.25 mm, df 0.12 μm