Development of a vacuum filtration system for the conventional microplate washer

IntroductionFilter plates are available from many vendors reflecting the growth of their scientific applications in various fields, however, the heterogeneous nature of those applications are the major factor to block the expansion of various filter plate options in a research scale operation. The development of an automatic vacuum filtration system for a conventional plate washer was presented as a possible solution for the filtration process in filter plate applications, especially in the melanin concentrating hormone receptor subtype 1 (MCH1) receptor binding assay with the time resolved fluorescence technology.MethodsThe pilot modification was done in the Embla 96/384 well washer by replacing the original plate carriage with a new carriage mimicking the conventional vacuum manifold to add the function of flow-through vacuum filtration for filter plates. The performance of new vacuum filtration system was evaluated with MCH1 receptor binding assay and ligand washout experiments.ResultsThe mean background values from ligand washout experiments in AcroWell filter plates were 6406 ± 502.9 with a manual vacuum manifold and 5563 ± 585.8 with the vacuum filtration system. Z′ factors were calculated as 0.6101 ± 0.095 for the MCH1 receptor binding assay with the vacuum filtration system.DiscussionThe new plate carriage for a conventional plate washer was developed for filter plate applications to enable its use in a flow-through vacuum filtration application in addition to the conventional plate washing by an aspiration. The results from ligand washout and receptor binding assay suggest that the vacuum filtration system can provide a cost-effective solution for filter plate applications and may alleviate the most common problems of those heterogeneous assays to develop as high throughput operations without major investments for the professional workstations.