Proteolytic-based method for the identification of human growth hormone

Area of Science:

• Forensic Science
• Biochemistry
• Analytical Chemistry

Background:

• Human growth hormone (HGH) is a 191-amino acid protein crucial in various physiological processes.
• Forensic analysis of proteins requires robust methods to meet laboratory and legal standards.
• Current methods for HGH identification involve chromatographic and mass spectrometric techniques.

Purpose of the Study:

• To present a proteolytic approach for the forensic analysis of human growth hormone (HGH).
• To enhance the specificity and reliability of HGH identification in unknown samples.
• To ensure the analytical method meets the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) recommendations.

Main Methods:

• Analysis of intact HGH using high-performance liquid chromatography with photodiode array detection and liquid chromatography-mass spectrometry (LC-MS).
• Proteolytic digestion of HGH using porcine trypsin to generate peptide fragments.
• In silico digestion of HGH to predict theoretical peptide fragments.

Main Results:

• The proteolytic digestion yielded 21 predicted peptide fragments of varying lengths.
• Larger peptide fragments provide increased specificity for protein identification.
• The combined approach of intact protein analysis and peptide fingerprinting offers a comprehensive identification strategy.

Conclusions:

• The proteolytic digestion method, coupled with LC-MS, provides a highly specific approach for HGH identification.
• This method meets SWGDRUG recommendations for the identification of unknown substances in forensic contexts.
• The strategy enhances the analytical sufficiency for forensic protein analysis.