Probably, you have peaks at 230 and 280 nm. The peak at 230 nm is due

to absorbance by peptide bonds. The peak at 280 nm results from absorbance by the rings of aromatic amino acids (tryptophan, tyrosine, and phenylalanine).This is normal. If there are other signals as well, you might have contamination. Best, Christoph

I am agreeing with Dr. Wittmann. The peak at 230 nm is due to absorbance by the peptide bonds while the 280 nm peak is due to absorbance by the rings of aromatic amino acids (tryptophan, tyrosine, and phenylalanine). Refer the details in the attachement.

Navaneethaiyer Umasuthan, thanks