In addition to our range of silicagels we are offering sulfonated styrene-divinyl resins (GROM Polymer Phases) for the analysis of organic acids, carbohydrates, und sugar alcohols. The resins are available in the H-form (H+IEX), sodium-form (Na+IEX), Calcium-form (Ca++IEX), and in the lead-form (Pb++IEX). For the polymeric columns up to 40% acetonitrile, 30% ethanol, or 5% isopropanol are used as organic eluents. Methanol should not be applied. Organic columns should be washed for some hours with acetonitrile/water (30/70). Contaminations by metal ions are removed for the calcium-form column with a solution of 0.1 M calcium nitrate, for the H+-form column with 0.1 M sulfuric acid. The storage of the columns is done under water or under 0.1 M sulfuric acid, respectively. |