Recent studies have discovered that the isotopic composition of molybdenum (Mo) is variable in a wide range of geological materials such as molybdenites and marine sediments (e.g., black shales and Fe-Mn nodules). A number of analytical techniques, such as double spiking and standard-sample bracketing (SSB), have been used to measure mass-dependent Mo isotopic variations in geological samples by multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). These techniques make it possible to correct for instrumental mass-dependent isotopic fractionation (i.e., instrumental mass bias) found in the MC-ICP-MS, which masks the natural mass-dependent isotopic variations. In order to obtain accurate Mo isotopic measurements by MC-ICP-MS using SSB (the technique employed in this study), it is necessary to avoid or correct for any matrix effects, which may bias the data. Matrix effects have been shown to cause deviations in the apparent isotopic composition of a sample or standard determined by MC-ICP-MS relative to its true isotopic composition. Previously, no studies have evaluated any potential matrix effects related to the chemical separation and purification of Mo from geological samples using ion-exchange chromatography (i.e., "column chemistry"). Here I evaluate the use of anion exchange resin for Mo separation and purification, which is required for the analysis of Mo from silicate rocks and minerals. My results demonstrate that significant matrix effects are induced by column chemistry. Specifically, (1) the average Mo isotopic composition of a standard passed through the anion exchange resin becomes significantly different from the expected value, (2) this Mo isotopic shift is caused by the presence of an organic matrix that is stripped from the resin into the standard solution, and (3) a scaled-down version of the anion resin column chemistry can remove much, but not all, of this organic matrix (and the resulting matrix effect). Thus, I was unable to completely remove the matrix effect induced by the column chemistry. Although the use of the scaled-down column is promising, it is probable that the use of a double spike to correct for instrumental mass bias may be the only analytical technique that provides accurate and precise Mo isotopic data by MC-ICP-MS.