Analytical Cation Exchange Columns and Resins

Columns and Resins Pic

St. John Associates has offered the finest cation exchange resins and columns for over 18 years. Some facts about our products:

  • We're the best for Amino Acid Analysis -- High speed analyses require the very finest in cation exchange resin.
  • We make our resin in house from scratch -- We synthesize our own resin directly from styrene and divinyl benzene.
  • We prepare our resin in small batches to order -- We carefully sulfonate and size our resins, resulting in incomparable performance.
  • We have the experience you need -- Decades of experience packing and testing narrow bore columns ensures that our pre-packed columns provide peak performance for a variety of applications.

Read more about our columns...

Read more about our resins...


Columns Pic

St. John Associates' packs each of its cation exchange columns with 8% crosslinked sulfonated polystyrene resins. These premium columns support high-resolution separations of amino acids, ammonia, amino sugars, organic acids, primary amines and related compounds. We ship these columns ready-to-use with 0.2M sodium citrate, formate or acetate elution methodologies.

Constructed of type 316 stainless steel tubing, St. John Associates' columns are passivated and polished according to a proprietary process. For increased compatibility we use industry standard "reversed" fittings with 10-32 x 1/16" cone ferrule inlets and outlets. Additionally, St. John Associates columns are symetrical, allowing you to reverse flow for easy contaminant removal from the inlet frit.

Available column sizes include:

  • 0.46 x 10cm
  • 0.46 x 15cm
  • 0.46 x 25cm

  • 0.32 x 10cm
  • 0.32 x 15cm
  • 0.32 x 25cm

  • 0.24 x 10cm
  • 0.24 x 15cm
  • 0.24 x 25cm


Resin Pic

St. John Associates' Cation Exchange Resins include 8% crosslinked, fully solufonated polystyrene resins particularly suited for use with 1.8mm to 4.6mm high-efficiency columns. Our new, proprietary synthesis methods produce a polymer matrix of unusual homogeneity and purity. The resulting resin exhibits low color throw, high stability to acids & bases and very high chromatographic efficiency. St. John Associates resins make an ideal replacement for Beckman's AA-10, Spherogel, Durrum or Dionex DC4A resins and BioRad's Aminex A7 and Aminex A8 resins.

Sizing: We tightly size our resins to an average deviation of +/- 0.5 micron from the mean particle diameter. We offer 1 gram lots of sizes ranging from 4.5 microns to 8 microns in 0.5 micron increments. Additionally, we offer 25 gram lots of 8.5 micron and 12 micron resins.

For More Information...

See our contact page or call St. John Associates directly at 1-800-837-2023.