The study of metabolites in biological samples is of high interest for a wide range of biological and pharmaceutical applications. Reversed phase liquid chromatography is a common technique used for the separation of metabolites, but it provides little retention for polar metabolites. An alternative to C18 bonded phases, porous graphitic carbon has the ability to provide significant retention for both non-polar and polar analytes. The goal of this work is to study the retention and effective diffusion properties of porous graphitic carbon, to see if it is suitable for the wide injection bands and long run times associated with long, packed capillary-scale separations. The retention of a set of standard metabolites was studied for both stationary phases over a wide range of mobile phase conditions. This data showed that porous graphitic carbon benefits from significantly increased retention (often >100 fold) under initial gradient conditions for these metabolites, suggesting much improved ability to focus a wide injection band at the column inlet. The effective diffusion properties of these columns were studied using peak-parking experiments with the standard metabolites under a wide range of retention conditions. Under the high retention conditions, which can be associated with retention after injection loading for gradient separations, D_eff/D_m ∼ 0.1 for both the C18-bonded and porous graphitic carbon columns. As C18 bonded particles are widely, and successfully utilized for long gradient separations without issue of increasing peak width from longitudinal diffusion, this suggests that porous graphitic carbon should be amenable for long runtime gradient separations as well.

生物样品中代谢物的研究对于广泛的生物和制药应用具有​​很高的兴趣。反相液相色谱法是用于代谢物分离的常用技术，但对极性代谢物的保留很少。作为C18键合相的替代品，多孔石墨碳具有为非极性和极性分析物提供显着保留的能力。这项工作的目的是研究多孔石墨碳的保留和有效扩散特性，以查看其是否适合宽的注入谱带和较长的填充时间，以及较长的填充毛细管规模分离。研究了一组固定代谢物在多种流动相条件下对两种固定相的保留。该数据表明，在初始梯度条件下，这些代谢物的保留时间显着增加（通常> 100倍），多孔石墨碳受益匪浅，表明将宽进样带聚焦在色谱柱入口处的能力大大提高。在宽范围的保留条件下，使用峰代谢与标准代谢物研究了这些色谱柱的有效扩散性能。在高保留条件下，这可能与进样后进行梯度分离的保留有关，在宽范围的保留条件下，使用峰代谢与标准代谢物研究了这些色谱柱的有效扩散性能。在高保留条件下，这可能与进样后进行梯度分离的保留有关，在宽范围的保留条件下，使用峰代谢与标准代谢物研究了这些色谱柱的有效扩散性能。在高保留条件下，这可能与进样后进行梯度分离的保留有关， 对于C18键合和多孔石墨碳柱，D _eff / D _m均约为0.1。由于C18键合的颗粒广泛且成功地用于长梯度分离，而没有因纵向扩散而增加峰宽的问题，这表明多孔石墨碳也应适用于长时间的梯度分离。