When running peptide standard a stable baseline was observed but my samples are giving a very significant baseline drift (wavy)?
To be precise protein samples were digested in 6N HCl and were then neutralised with NaOH followed by freeze drying. 100 mg of freeze dried samples were then dissolved in MQ water to be analysed by HPLC for peptide formation, but it started giving unstable baseline. Also the same column and mobile phase gave stable baseline when peptide standard from sigma aldrich was analysed before the samples.