Mass Spectrometry (LC-MS / HRMS) Molecular ID
High-Resolution Exact Mass Verification, Multivalent Charge Deconvolution, and Molecular Fingerprinting for Synthetic Peptides, Oligonucleotides, and Complex Organics.
Exact Mass Determination & Structural Confirmation
While HPLC establishes chromatographic purity by measuring relative peak area, Liquid Chromatography-Mass Spectrometry (LC-MS) provides unambiguous chemical identity by determining the exact monoisotopic and average molecular mass of target molecules.
Utilizing our Thermo Scientific Orbitrap Exploris platform, specimens are gently ionized via Electrospray Ionization (ESI). Intact multivalent gas-phase ions ([M+H]+, [M+2H]2+, [M+3H]3+, [M+4H]4+) are separated according to their mass-to-charge ratio (m/z) with resolving power exceeding 120,000 FWHM. Automated deconvolution algorithms convert complex multivalent spectral envelopes into a single neutral average molecular mass, confirming peptide synthesis accuracy against theoretical stoichiometric calculations.
What Orbitrap HRMS Uncovers
High-resolution spectral analysis capable of distinguishing isobaric modifications and adduct formations.
Charge State Deconvolution
Accurate mathematical reconstruction of neutral molecular weight from envelope distributions (z = 1 through z = 8) across high-mass peptides and proteins.
Adduct & Counter-Ion Identification
Detection of sodium ([M+Na]+), potassium ([M+K]+), ammonium ([M+NH4]+), and trifluoroacetate ([M+TFA]-) ionic adducts.
Synthesis Truncation & Insertion Errors
Pinpoints deletion of single amino acid residues (e.g. missing glycine -57 Da or alanine -71 Da) or unexpected protecting group remnants (+100 Da Boc, +222 Da Fmoc).
Certified Isotope Envelope Report
Every COA features the raw ESI mass spectrum showing experimental vs. theoretical isotopic cluster overlay with measured mass delta (Δ Da).
Operating Parameters (SOP-MS-02)
| Parameter | Instrument Setting | Operational Target |
|---|---|---|
| Mass Analyzer | Thermo Scientific Orbitrap Exploris Mass Spectrometer | Ultra-high-resolution electrostatic trap |
| Ionization Source | Heated Electrospray Ionization (H-ESI II) | Positive & Negative polarity switching |
| Resolving Power | 120,000 FWHM @ m/z 200 | Resolves isotopic fine structures |
| Mass Accuracy | < 1.0 ppm with internal fluoranthene lock-mass calibrant | Absolute delta < 0.5 Da on intact peptides |
| Spray Voltage & Temp | 3.50 kV spray voltage, 320°C capillary temperature | Prevents thermal fragment degradation |
| Sheath & Aux Gas | N₂ Sheath: 45 Arb; Aux: 10 Arb; Sweep: 2 Arb | High-purity 99.999% laboratory nitrogen |
| Mass Scan Range | m/z 150 – 4,000 (extended mode up to 6,000) | Accommodates large GLP-1 analogues & proteins |
Submission Guidelines for Mass Spec
- Sample Amount: 2 – 3 mg dry lyophilized powder or 1 intact sealed vial.
- Solubility: Water, 50% Acetonitrile, or dilute acetic acid soluble matrices preferred. Avoid non-volatile detergents (SDS, Triton X).
- Blind Submission: Provide molecular formula or expected target mass if known, or request de novo unguided molecular weight determination.
- Combined Panel Recommendation: Combine with Quantitative HPLC Purity for complete analytical certification.