We haven't found a great primary (or secondary) antibody, but we have used the NTA Atto 488 dye (Sigma 39625) with some success at primary detection of His-tagged proteins directly in our gels, without the need for a transfer step to a membrane. We run BSA alongside our samples to determine the amount of non-specific binding and it is usually very low. Our collaborators use the InVision kit from Invitrogen (similar dye) after a crude NTA purification, and it only picks up the protein of interest. It might be worth a try depending on your needs, but I'm not sure of the detection limits of this dye.
Lauren Boucher -------- Bosch Lab|Johns Hopkins School of Public Health 615 N Wolfe St, W8710|Baltimore, MD 21205 [email protected]
