Dahal Kaushalya Sharma, Gamagedara Sanjeewa, Nuwan Perera Undugodage Don, Lavine Barry K
Department of Chemistry, Oklahoma State University, Stillwater, OK 74078.
Department of Chemistry, University of Central Oklahoma, Edmond, OK 73034.
J Liq Chromatogr Relat Technol. 2019;42(19-20):681-687. doi: 10.1080/10826076.2019.1666275. Epub 2019 Sep 18.
The problem of longer retention times using water-rich mobile phases in reversed phase liquid chromatography (RPLC) has been addressed using hydrophobic alcohols such as butanol in very low quantities (approximately 0.1%) as the organic modifier. Advantages of water-rich mobile phases in RPLC for the separation of water-soluble and weakly retained compounds are improved separation of congeners and better tuning of RPLC separations. This is demonstrated in the separation of gentisic acid and related renal cell carcinoma (RCC) biomarkers in urine with a Zorbax C column and a mobile phase of 0.1% (volume/volume) butanol in water with 0.6% (volume/volume) acetic acid. Calibration curves for the RCC biomarkers were linear over the concentration range investigated (5 ppm to 1000 ppm). Detection limits for the RCC biomarkers were 0.85ppm (quinolinic acid), 1.75ppm (gentisic acid), and 1.25ppm (4-hydroxybenzoic acid). Recovery tests using synthetic urine samples containing 20 ppm, 100 ppm, and 700 pm of each RCC biomarker were successful for all compounds.
在反相液相色谱法（RPLC）中，使用极少量（约0.1%）的疏水性醇类（如丁醇）作为有机改性剂，解决了使用富含水的流动相时保留时间较长的问题。在RPLC中，富含水的流动相用于分离水溶性和弱保留化合物，其优点是同系物分离得到改善，RPLC分离的调节性更好。这一点在使用Zorbax C柱和含0.1%（体积/体积）丁醇及0.6%（体积/体积）乙酸的水相流动相分离尿液中的龙胆酸及相关肾细胞癌（RCC）生物标志物时得到了证明。在所研究的浓度范围（5 ppm至1000 ppm）内，RCC生物标志物的校准曲线呈线性。RCC生物标志物的检测限分别为0.85 ppm（喹啉酸）、1.75 ppm（龙胆酸）和1.25 ppm（4-羟基苯甲酸）。使用含有20 ppm、100 ppm和700 ppm每种RCC生物标志物的合成尿液样本进行的回收率测试，对所有化合物均成功。
