Since the 1950’s, liquid chromatography columns have relied on randomly structured packed-bed or monolith stationary phases. After decades of incremental improvement, this technology is reaching its limits. The inherent unordered nature leads to peak dispersion, limited separation efficiency and poor reproducibility.
µPACᵀᴹ pillar array chromatography introduces a paradigm shift by fundamentally rethinking the type of stationary phase used to achieve separation and introducing perfect order.
µPACᵀᴹ separation beds are formed by carefully etching away the interstitial volumes out of a solid silicon wafer, leaving an array of pillars. The resulting channels are folded onto a small footprint by concatenating bed segments with optimized flow distributors that limit peak dispersion. This creates a stationary phase support structure that is organized in a reproducible, perfectly ordered pattern.
µPACᵀᴹ separation beds are designed with a high degree of order, eliminating heterogeneous flow paths otherwise present in conventional columns (so called eddy dispersion). Flow through µPACTM columns adds very little dispersion to the overall separation. As a result, peaks remain sharper, plate counts are higher, and sensitivity is increased.
The micromachined backbone of the separation bed forms a solid fritless structure that is not influenced by pressure. There are no obstructions by touching surfaces, and there is no risk for perturbations by pressure fluctuations. This results in an extreme robustness allowing more sample injections without losing performance.
Due to the mask-based etching process, every µPACᵀᴹ column is perfectly identical and yields the same results over time and across laboratories. This reproducibility enables collecting data that is sufficiently consistent for big data analysis.