title: Batch-to-batch variation of Chelex-100 confounds metal-catalysed oxidation. Leaching of inhibitory compounds from a batch of Chelex-100 and their removal by a pre-washing procedure.
abstract: Removal of adventitious redox-active metals from buffers by treatment with Chelex resin is a widely used procedure in free radical research. Use of a new batch of Chelex-100 resin in our laboratory coincided with a sudden inability to oxidise low-density lipoprotein with copper. We found that copper-mediated oxidation of ascorbate in water treated with the same batch of Chelex was inhibited when compared with untreated water and water treated with a different batch of the resin. Washing the Chelex removed the inhibitory effect suggesting that material was leaching from the resin. The washing procedure for Chelex-100 described is simple and can be scaled up. Oxidation of ascorbate with low concentrations of copper can be used to test the quality of batches of the resin.
authors.affiliation: Cell Biology Group, Heart Research Institute, Sydney, NSW, Australia.
authors.forename: D M
authors.initials: DM
authors.lastname: Van Reyk
authors.forename: A J
authors.initials: AJ
authors.lastname: Brown
authors.forename: W
authors.initials: W
authors.lastname: Jessup
authors.forename: R T
authors.initials: RT
authors.lastname: Dean
mesh_terms: D002384:Catalysis; D002411:Cation Exchange Resins; D002614:Chelating Agents; D003300:Copper / Q000737:chemistry*; D008077:Lipoproteins, LDL / Q000737:chemistry*; D008832:Microchemistry; D010084:Oxidation-Reduction; D015203:Reproducibility of Results; D012117:Resins, Synthetic; D014867:Water / Q000737:chemistry
chemical_list: D002411:Cation Exchange Resins; D002614:Chelating Agents; D008077:Lipoproteins, LDL; D012117:Resins, Synthetic; D014867:Water; C024997:Chelex 100; D003300:Copper