We successfully fabricated 45 μm bore microchannels in PVA-Poly(styrenesulfonate) cation exchange polymers. by casting aqueous prepolymer mixtures around fine tungsten wire mandrels, curing, crosslinking by thermal annealing, and subsequently removing the microwire. This was then used as a chemically regenerated microsuppressor (with a cleaner MS background than its commercial macro counterparts) for open tubular ion chromatography, with an integrated tubular conductivity cell, tested to backpressures up to 600 psi. The overall system permits detection limits for common inorganic ions in the low μg/L levels with a 4-nL injection, isocratic elution and regeneration with poly(styrene sulfonic acid).