Haider Richard, Sartori Barbara, Radeticchio Andrea, Wolf Marcell, Dal Zilio Simone, Marmiroli Benedetta, Amenitsch Heinz
Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/IV, 8010 Graz, Austria.
Research Neutron Source Heinz Maier-Leibnitz (FRM II), Technical University of Munich, Lichtenbergstraße 1, 85748 Garching, Germany.
J Appl Crystallogr. 2021 Feb 1;54(Pt 1):132-141. doi: 10.1107/S1600576720014788.
An automatic sample changer system for measurements of large numbers of liquid samples - the µDrop Sample Changer - is presented. It is based on a robotic arm equipped with a pipetting mechanism, which is combined with a novel drop-based sample holder. In this holder a drop of liquid is suspended between two parallel plates by surface tension. The absence of a transfer line benefits the cleaning, improving the background as well as making it faster and more efficient than most comparable capillary-based systems. The µDrop Sample Changer reaches cycle times below 35 s and can process up to 480 samples in a single run. Sample handling is very reliable, with a drop misplacement chance of about 0.2%. Very low sample volumes (<20 µl) are needed and repeatable measurements were performed down to 6 µl. Using measurements of bovine serum albumin and lysozyme, the performance of the instrument and quality of the gathered data of low and high concentrations of proteins are presented. The temperature of samples can also be controlled during storage and during measurement, which is demonstrated by observing a phase transition of a mesophase-forming lipid solution. The instrument has been developed for use in small-angle X-ray scattering experiments, which is a well established technique for measuring (macro-)molecules. It is commonly used in biological studies, where often large sets of rare samples have to be measured.
介绍了一种用于大量液体样品测量的自动进样器系统——µDrop进样器。它基于一个配备移液机制的机械臂，并与一种新型的基于液滴的样品架相结合。在这个样品架中，一滴液体通过表面张力悬浮在两个平行板之间。没有传输线有利于清洁，改善背景，并且使其比大多数类似的基于毛细管的系统更快、更高效。µDrop进样器的循环时间低于35秒，单次运行可处理多达480个样品。样品处理非常可靠，液滴错放的几率约为0.2%。所需样品体积非常小（<20µl），并且对低至6µl的样品进行了可重复测量。通过对牛血清白蛋白和溶菌酶的测量，展示了该仪器的性能以及所收集的低浓度和高浓度蛋白质数据的质量。在样品储存和测量过程中也可以控制样品温度，通过观察一种形成中间相的脂质溶液的相变来证明这一点。该仪器是为用于小角X射线散射实验而开发的，小角X射线散射是一种用于测量（大）分子的成熟技术。它常用于生物学研究，在生物学研究中经常需要测量大量稀有的样品。
