Chelex® 100 Iron Form Resin for
Glyphosate Clean-UpIntroduction
Glyphosate, a popular herbicide used to destroy unwanted
weeds, has been sold and marketed as Kleenup®2 andRoundup®3 weedkiller. Because the EPA has set limits on theconcentration of glyphosate in food products and water supplies, an HPLC method using the HRLC® glyphosate analysis
column has been developed for the detection of glyphosate andits breakdown product, AMPA (aminomethyl phosphonicacid).1 Prior to injecting onto the column, the sample should
first be cleaned up with Chelex 100 100-200 mesh resin in theiron form, and AG® 1-X8 resin 200-400 mesh in the chlorideform.

Product Description
Chelex 100 resin is a styrene divinylbenzene copolymer containing iminodiacetate ions. The iron form resin has iron (III)ionically bound to the iminodiacetate ions, which act to chelate
the glyphosate from environmental water and crops such as
soybeans, grapes, cabbage, and alfalfa.1 Because the iron form
Chelex 100 resin is of analytical grade, pre-treatment of theresin prior to sample loading is not necessary.

Instructions for Sample Clean-up
with Chelex 100 Resin
1.

Transfer 15 ml of Chelex 100 100-200 mesh resin, ironform, to a column containing 7-8 ml of deionized water.

2.

Apply the sample to the column and eluate at a rate of 68 ml/min.

3.

After the elution of the sample, rinse the walls of the column and resin bed with approximately 560 ml of deionized after.

4.

Rinse the column with an additional 100 ml of 0.2 M HCl,with a full open column stopcock.

5.

Discard all eluates.

6.

Eluate the glyphosate, at a rate of 4 ml/min or less, with 22ml of 6 M HCl.

7.

Retain only the last 15 ml of eluate and combine with 10
ml of concentrated HCl for an ion exchange clean-up.

Instructions for Sample Clean-up
with AG 1-X8 Resin
8.

Prepare the column by adding 7-8 ml of deionized waterand approximately 7 ml of AG 1-X8 200-400 mesh resin,
chloride form.

9.

Adjust the resin bed height to 5 cm.

10. Rinse the column with 15 ml of 6 M HCl immediately
before applying the sample.
11. Apply the eluate from the Chelex 100 resin clean-up procedure (from step 7 above) with the stopcock full open.
12. Quickly rinse the sample container with 2 ml of 6 M HCl,and apply the rinse to the column.
13. Just as the last of the sample and rinse enters the column,
apply 8 ml of 6 M HCl and collect the eluate in a 250 ml
recovery flask.
14. Concentrate the eluate by drying on a rotary film evaporator, slowly increasing the temperature of the water bathfrom 20 to 60° C.
15. Remove the final traces of moisture with a stream of dry
nitrogen.
16. Dissolve the residue in 2.0 ml of deionized water and filter through a 0.45 mm Uni-Pore® syringe filter prior toquantification of glyphosate on the HRLC glyphosate analysis column.

References
1. Cowell, J., et al., J. Agric. Food Chem., 34, 955 (1986).
Kleenup® is a registered trademark of Chevron Corporation.
Roundup® is a registered trademark of Monsanto Company.

Ordering Information
Catalog
NumberProduct
Description

PackageSize

142-2825

Chelex 100 Resin, iron form,
100-200 mesh

100 g

140-1451

AG 1-X8 Resin, chloride form,
200-400 mesh

500 g

125-0104

Glyphosate Analysis Column,
300 x 4.6 nm

1125-0106

Glyphosate Analysis Column,
250 x 4.6 mm

1125-0108

Glyphosate Analysis Column,
100 x 4.6 mm

1343-0112

0.45 mm Uni-Pore Filter50© 1990 Bio-Rad Laboratories.
All Rights Reserved.

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