The conventional method for desalting columns in proteomic sample pre-treatment is a multi-step process and is susceptible to trace sample loss. This study presents a novel proteomic pre-treatment method that combines enzymatic digestion with ultrafiltration and desalting through a one-step heating process. The procedure involves washing protein samples with ammonium bicarbonate prior to enzymatic digestion, and subsequently removing ammonium bicarbonate from the resulting peptide solution by heating to yield pure, desalted peptides. This approach is simple to implement, does not result in sample loss or contamination from PEG polymers, and can be directly interfaced with LC-MS for subsequent mass spectrometry analysis.