If antibodies are the only protein in the solution, any protein quantification method should work, right? Lowry, Bradford, BCA can be measured in a simple colorimeter or absorbance microplate reader, or some fluorescent kit if you have a fluorescence reader.

Francesc Felipe , the antibody will be the one in solution . I'm an organic chemistry, I admit I have no idea about these methods but I'll learn them. Thank you so much

Dear Laetitia Mistico

if do you have any other UV-VIS spectrophotometer you can use it instead nanodrop to determine the A280nm and afterwards extrapolate the mab concentration considering that the molar exctinction coefficient of a mab is around 210,000M-1 cm-1.

Theoretically at 280nm, you have to use quartz cell to obtain reailable determination since standard plastic in not trasparent to UV but there are actually many commercial plastic cuvettes that has low absorbance at 280nm and therefore could be used. Just look to the absorbance of your empty cuvette before perform the experiment. If it is relativelly low (max0.1-0,2 you can proceed, if it is high eg. 0.5 or more) is it better to found a better cuvette

best

Manuele