The above results shows the linear working range of the Complex I dipstick activity assay using mrc5 whole cell protein extract. The dipstick results are both quantitative and highly reproducible (intra-assay error less than 10%). The developed dipsticks can be analyzed with a simple flat-be scanner and common imaging software or, for sensitive and reproducible results, a dipstick reader can be utilized (our suggested reader: Hamamatsu ICA-1000).