Are your standard curve samples giving a value?

Dear sir

Thanks for the response. But for MDA, why do we need to make standards. We need to make standards for PROLINE estimation. I am following TBA methods for the analysis of MDA.

With thiobarbituric acid you are forming a coloured adduct with your malondialdehyde. You need to make a standard curve using MDA samples of a known concentration if you want to do quantification with your other samples. The standards also act as positive controls that your method is working.