Tissue homogenate standards were also strongly affected by incubation time (Figure 2). The best dynamic range and reliabilty were seen with the 60 min incubation time. The slope of the 30 min incubation time (.0099 +- .0012) was much more shallow than the slopes seen in 60 (.0224 +- .0009) and 90 min (.0281 +- .0044) incubation times (Figure 2). Finally the R2 values across the incubation times (0.91, 0.99 and 0.83 respectivly) show that the homogenate was most reliably linear when measured after 60 min (Figure 2). All models account for the batch effect which is due to unknown factors and is commonly seen in this assay. This batch effect was consistent across time points.