Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan 11529.
Anal Chem. 2010 Oct 1;82(19):8283-90. doi: 10.1021/ac1017937.
The existence of surfactants in proteomics samples can severely reduce enzymatic digestion efficiency, liquid chromatography (LC) separation efficiency, column lifetime, and mass spectrometry (MS) sensitivity. Although various techniques are able to remove surfactants, surfactants may occasionally be retained in samples due to variations in sample preparation method or personal skill. Evaluation of surfactant residue in a sample, however, usually requires an additional instrument and is time-consuming. In this study, a simple and rapid visual indicator for surfactant abundance (VISA) was developed. With the detection of a visible surfactant pellet in the solution, this assay was able to detect surfactant residue in aqueous solutions within 5 min. Without the need of additional equipment such as a mass spectrometer, every user can perform a quick test on their bench before sending the sample to the MS facility. The detection limit for the commonly used surfactants, Triton X-114 and SDS, was about 0.0005% and 0.0002%, respectively. The VISA was successfully applied to evaluate the efficiency of removal of surfactants in Triton X-114 extracted membrane proteins using tube-gel. With the combination of Triton X-114 extraction and tube-gel protocol, a study of spermatozoa membrane proteome identified about 252 proteins of which about 67.5% were classified as membrane proteins. The coexistence of protein and surfactant did not affect the VISA sensitivity, suggesting that this indicator is suitable for proteomics applications. The VISA also has potential for the detection of other surfactants and can be applied to other surfactant removing protocols.
表面活性剂存在于蛋白质组学样品中会严重降低酶解效率、液相色谱（LC）分离效率、色谱柱寿命和质谱（MS）灵敏度。尽管有各种技术可以去除表面活性剂，但由于样品制备方法或个人技能的差异，表面活性剂偶尔会残留在样品中。然而，评估样品中表面活性剂的残留量通常需要额外的仪器且耗时。在本研究中，开发了一种简单快速的表面活性剂丰度可视化指示剂（VISA）。通过检测溶液中可见的表面活性剂颗粒，该测定法能够在 5 分钟内检测到水溶液中的表面活性剂残留。不需要额外的仪器，如质谱仪，每个用户都可以在将样品送到 MS 设备之前在自己的实验台上进行快速测试。该检测法对常用表面活性剂 Triton X-114 和 SDS 的检测限分别约为 0.0005%和 0.0002%。VISA 成功应用于评估 Triton X-114 提取膜蛋白时管胶法去除表面活性剂的效率。通过 Triton X-114 提取和管胶方案的结合，对精子膜蛋白质组学的研究鉴定了约 252 种蛋白质，其中约 67.5%被归类为膜蛋白。蛋白质和表面活性剂的共存并不影响 VISA 的灵敏度，表明该指示剂适用于蛋白质组学应用。VISA 还具有检测其他表面活性剂的潜力，并可应用于其他表面活性剂去除方案。
