Human Growth Hormone amount, purity and dimer and higher molecular weight proteins analysis

This analysis is designed to identify Human Growth Hormone 191 AA and determine its amount and purity. The test also includes separate measurement of HGH dimer and higher molecular weight proteins, which are important quality parameters for growth hormone products.

Human Growth Hormone 191 AA

Human Growth Hormone, also known as HGH, somatropin or recombinant human growth hormone (rHGH), is a peptide hormone composed of 191 amino acids. It is naturally involved in the regulation of growth, metabolism and other physiological processes.

Somatropin used in pharmaceutical products is a recombinant form corresponding to the naturally occurring 191-amino-acid human growth hormone. Product quality depends not only on HGH content and purity but also on the presence of dimers and other higher molecular weight protein forms.

An HGH dimer is formed when two growth hormone molecules associate with each other. Because the dimer is still composed of HGH molecules, it may not be classified as a conventional impurity by a standard purity test. A separate analysis is therefore required for its accurate measurement. Increased levels of dimers and other high-molecular-weight protein forms may affect product quality, activity and tolerability.

What the Analysis Determines

• Identity of HGH 191 AA
• Amount of HGH in the sample
• Growth hormone purity
• Dimer content
• Higher molecular weight protein content
• Results in a format appropriate for the submitted sample type

Analysis Parameters

• Target compound: Human Growth Hormone 191 AA
• Other names: somatropin, HGH, rHGH, 191 AA
• Molecular weight: 22,124 Da
• Testing method: HPLC
• HGH detection limit: 0.2 mg/ml or 0.5 mg/vial
• Dimer and higher molecular weight protein detection limit: 0.008%
• Result format for lyophilizates: mg/vial, IU, purity percentage and dimer percentage
• Result format for liquids: mg/ml, IU, purity percentage and dimer percentage
• Alternative result format: m/m purity, GH purity and dimer percentage
• Minimum lyophilizate sample: one whole unopened vial containing the lyophilizate
• Minimum liquid sample: 1 ml
• Minimum raw API powder sample: 30 mg in a sealed glass vial to prevent moisture absorption
• Average turnaround time: 7 business days

Important Notice

Only the 191-amino-acid form of HGH is recognized as Human Growth Hormone by this analytical method. HGH 192 AA is not a target of the test and its presence would result in “HGH not detected” being stated in the report.

The alternative m/m purity result format is intended exclusively for raw API powders. Lyophilized products are normally reported in mg/vial, while liquid samples are reported in mg/ml.

Additional Analyses

TFA Analysis

• Detection and measurement of trifluoroacetic acid (TFA) in the sample. Results are reported in mg per vial.

Raw Data

• Delivery of the available raw analytical data from the primary test and all applicable additional analyses.

Fentanyl Presence Analysis

• Screening of the sample for the presence of fentanyl.

Alternative Result Format – m/m Purity

• Alternative reporting of the result as mass-by-mass purity. This option is intended exclusively for raw API powders.

Variance Testing with Dimer Analysis

• Analysis of multiple vials from the same batch to evaluate variation in HGH content, purity and dimer levels. Dimer content is measured in every submitted vial.

Variance Testing

• Analysis of multiple sample units from the same product batch to assess variation between individual vials or units. Dimer is not measured in the additional samples under this option.

pH Measurement

• Measurement of the sample’s pH value.

Endotoxin Analysis

• Measurement of bacterial endotoxins, particularly lipopolysaccharides (LPS), in the sample. This analysis is available only for finished products and should not be ordered for raw powders.
• The standard test provides accurate results up to 10 EU/vial. Values above 10 EU/vial are estimated and require an additional test with a different dilution for precise determination. Sending two vials is therefore recommended. Where endotoxin levels above 10 EU/vial are expected, the method can be calibrated for the higher range in advance.

CHNS Mass Report

• Elemental analysis providing accurate measurement of nitrogen and sulphur content. The results can be used to determine Net Peptide Content (NPC).

Additional Report

• A separate additional laboratory report issued under a different client name.

LC-MS Screening for Peptide Contamination

• LC-MS screening for contamination with other peptides or peptide degradation products. Detection is limited to peptides included in the laboratory’s available testing database.
• The initial screening provides identification only. If contamination is detected, quantitative measurement may subsequently be ordered.

Sterility Testing

• TAMC and TYMC testing checks the product for the presence of bacteria, yeasts and moulds. Additional unopened sample units must be submitted for the analysis. The average turnaround time for sterility testing is 14 days.

Heavy Metals Analysis

• Detection of selected heavy metals in the sample.