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Peptide & Protein Molecular Analysis

Advanced peptide and protein analysis lab services including molecular weight determination and structural characterization using cutting-edge mass spectrometry

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Send your peptide name, sample count, and the tests you need. We return a fixed-price quote, usually within one business day.

  • validated analytical methods, independent of any supplier
  • 5–7 business days for eligible routine testing
  • Traceable COA with chromatograms and method parameters
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Comprehensive Peptide & Protein Molecular Characterization

ACS Peptide Testing Labs provides professional peptide and protein analysis services with detailed molecular characterization using state-of-the-art mass spectrometry technologies including LC-MS/MS and ESI-MS. As an independent peptides testing laboratory, we confirm molecular weight, verify peptide identity, and identify post-translational modifications with the highest level of accuracy and reliability.

Molecular Weight Determination

High-resolution mass spectrometry for precise molecular weight measurement with accuracy better than 1 Da for peptides up to 15 kDa.

Structural Verification

Tandem MS/MS fragmentation analysis to verify peptide identity and detect structural errors or modifications.

Modification Analysis

Detection and characterization of post-translational modifications including phosphorylation, acetylation, and glycosylation.

Disulfide Bond Mapping

Determination of disulfide bond connectivity in peptides containing multiple cysteine residues using enzymatic digestion and MS.

Analytical Techniques

LC-MS/MS

Liquid chromatography tandem mass spectrometry for sequence verification and impurity identification

Documented Analytical Methods

ICH and USP referenced where applicable. Confirm the method and accreditation scope for your selected tests.

ESI-MS

Electrospray ionization for high-resolution mass analysis of intact peptides

Peptide Quantification

Accurate quantification methods to determine peptide concentration and content

Applications

  • • Verification of synthetic peptide identity before use in research
  • • Quality control for peptide manufacturing and production
  • • Identification of peptide degradation products and impurities
  • • Characterization of novel peptides isolated from natural sources
  • • Support for regulatory submissions requiring peptide characterization

Related Resources

HPLC vs Mass Spectrometry

When to use each method for peptide analysis.

Testing Glossary

Definitions for mass spectrometry and analytical terms.

Purity Testing

HPLC purity analysis for peptide quantification.

Molecular Analysis FAQ

Our high-resolution ESI-MS achieves accuracy better than 1 Da for peptides up to 15 kDa. For larger polypeptides, we use deconvolution algorithms to provide precise intact mass measurements.

Yes, we use LC-MS/MS fragmentation analysis to verify amino acid sequences. This method generates fragment ions that map to specific positions in the peptide chain, providing sequence coverage and confirming peptide identity.

We detect and characterize phosphorylation, acetylation, glycosylation, oxidation, deamidation, and other chemical modifications using high-resolution tandem mass spectrometry with specialized fragmentation techniques.

We require 0.5-1 mg of peptide sample, preferably lyophilized and shipped in a sealed container. Smaller quantities may be sufficient depending on the specific analysis requested.

ESI-MS (electrospray ionization mass spectrometry) measures the intact molecular weight of your peptide. LC-MS/MS adds chromatographic separation and fragmentation analysis, enabling sequence confirmation, impurity identification, and modification site localization.

Yes, mass spectrometry is the gold standard for identity verification. If the measured molecular weight doesn't match the expected peptide, it immediately reveals substitution, truncation, or a completely different compound. We compare against reference standards when available.

Eligible routine testing takes 5-7 business days from sample receipt. Sequencing and modification mapping have separately confirmed timelines.

Yes, our mass spectrometry methods can characterize peptides containing D-amino acids, N-methylated residues, β-amino acids, PEGylated sequences, and other non-natural building blocks. We adjust our fragmentation parameters and database searches to account for non-standard residue masses.

Yes, all molecular analysis reports include annotated spectra and deconvoluted mass data. Raw instrument files (.raw, .mzML) are available upon request for clients who want to perform their own data analysis or include raw data in publications.

Get Expert Molecular Analysis

Submit your peptides for precise molecular weight determination and structural characterization using advanced mass spectrometry.

(561) 513-8435cpierre@acslabtest.com