Filtration Assays

From Assay Guidance Wiki

Filtration whole membrane assays may be used for GTPγS binding using the same methods employed for radioligand binding. The potential advantages of filtration assays are the lack of non-proximity effects, which are present in SPA assays and the ability to use higher concentrations of GTPγ35S. Such advantages are not usually worth sacrificing the convenience of homogeneous SPA assays. There are many examples of the use of filtration for GTPγS binding in the literature (1,2,8, 9). As for WGA whole membrane binding, filtration assays are mostly limited to Gi/o coupled receptors since they cannot employ antibody capture.