Trusted Quality by KareBayTM
To assure various quality requirements on customer peptides, KareBay has developed and established quality management systems to assure the product conformities for both non-cGMP and cGMP products, and the documentations.

Non-GMP research peptides

To satisfy our customers, KareBay has conducted rigorous quality control testing procedures according to customer’s product specification. In general, our non-GMP peptides QC testing includes HPLC purity, identity testing by LC-MS, peptide content testing by AAA, and water content testing. Upon request, we can also provide the structure analysis of peptide or chemical using 1HNMR and 13CNMR, and element analysis for high purity of target compound.  Click for peptide quality controls 

HPLC Purity Sample Report

The peptide purity is determined by analytical RP-HPLC or RP-UHPLC with UV detector at 220 nm absorption wavelength.

Molecular Mass Found [M+H]+Sample Report

The molecular mass of the peptide is routinely determined by LC-MS (ESI-MS), and MALDI-TOF.

Peptide Content

The peptide content describes the percentage of peptides in the peptide sample (including required peptide, peptide impurity, counter ion, water, and other non-observeable materials). The peptide content is determined by amino acid analysis, and or elemental analysis.

Water Content

After the peptide production process, the peptides can absorb some moisture or water, depending on the hydrophobicity of the peptide. The water content of the peptide is determined by the standard Karl Fischer titration method.

Amino Acid Analysis (AAA)

The amino acid composition of the peptide product is determined by the standard amino acid analysis (AAA) methods. The peptide sample is hydrolyzed with hydrochloric acid (6N HCl), and then the amino acid composition is analyzed by RP-HPLC.

cGMP peptides

KareBay also provide cGMP manufacture services according to FDA/ICH standards and the quality management system of Karebay Biochem. The services include the process development studies, peptide manufacture, impurity studies, and full quality control testing reports. KareBay team has a well experienced team in developing, optimizing, manufacturing, and validating the process of analytical production. A typical cGMP peptide is tested in KareBay Biochecm is listed below various specifications.  Click for cGMP specific quality control 

Counter Ion Content

One of the major concerns of the processed peptide is the counter ions (i.e. TFA, HOAc, and others), which are mainly from purification process. The counterion content is quantified by chromatographic methods (HPLC, IC, or GC).

Residual Organic Solvent Content

Numerous organic solvents are used in peptide production, and the residual organic solvent content has significant effect on the quality of the peptide product. The Residual Organic Solvent Content is quantified by chromatographic methods (GC) according to USP standards.


The physical appearance of the processed peptides is verified visually by QC staff, and in general is reported as white or off-white powder.


The solubility of the peptide (mg/mL) depends on the sequence and hydrophobicity of the peptides, as well as other physical environment (solvents, pH, temperature, additives). Hydrophilic peptides are soluble in aqueous solution attenuated with pH. Hydrophobic peptides are difficult to dissolve, and some organic solvents and/or additives are required to dissolve these peptides.


Endotoxins are small bacterially-derived hydrophobic lipopolysaccharide (LPS) which can contaminate peptide product and underline process environments. The Endotoxin level (EU/mL) is determined by the standard Biochemical Assays


The stability of peptides greatly depends on peptide sequence as well as the process and storage conditions. Many peptide degradation processes are from Hydrolysis, Deamidation, Elimination, Oxidation, Racemization, Isomerization, DKP and pGlu/pAsp formation, Fragmentation, etc. The ideal peptide storage condition is at -20 o C. The stability studies profile of the peptide is designed, executed, monitored and documented by QC and production staff.

Bioburden Test

Bioburden test shows the unit counts of viable microorganisms in peptide product, and is important quality attribute in cGMP peptide production. Bioburden count is determined by the standard assay according to United States Pharmacopeia (USP) references.

A dedicated QA/QC department guarantees full cGMP compliance throughout production process, and all testing and documentation standards are in accordance with the strictest FDA/ICH requirements. KareBay has developed and maintained a robust quality assurance system covering all aspects required for the cGMP production of peptide APIs. Customers audit can be conducted whenever they deem necessary. All vendors of starting raw materials are carefully audited and evaluated by our auditing team (QA, QC, and Manufacture), and the qualified vendors will also provide a BSE free certificate. We will provide complete support for your IND and NDA fillings in documentation such as DMF or CMC and experiments. Continued regulatory assistance is provided by KareBay throughout process to make sure that our product conforms to the customers’ requirements.