Hello, everyone.

I am currently trying to develop a method to evaluate the extension of hydrolysis of whey proteins by several enzymes using the OPA assay (as proposed by Church et al. (1983) and adapted by Spellmann et al. (2003)). For this assay, 3.4 mL of OPA reagent are mixed with 10 uL of hydrolyzed sample -- it is a lot of reagent, and so I am trying to develop a way to make this measurement in a 96-well microplate. However, in order to keep the proportions for the mixture to fit the wells (maximum capacity of around 300 uL), I would have to add a very small amount of sample. This complicates things because this amount may not be representative and it is very hard to pipette such small aliquots.

Do you have any ideas on how to do this?

Thanks,

Gabriela.