Anybody here have a good experience and have had a workable internal control control for HIV serology using pooled HIV positive serum? Our lab have tried several times using a standard chart plotted using a serial dilution. The selected dilution for the IQC was 1: 32000 (as per protocol used in thai institute). 32 Microliters of Negative sera and 1 ML of pooled HIV positive was used as te Positive IQC material. However the OD on ELISA has not dropped following dilution with negative sera. Please do share if you have any experience working on it