Methods & instrumentation
How each number on the certificate is produced.
Nothing on a certificate is reported without the method that produced it and the specification it was judged against. This page states both for all eleven analytes.
Two independent lines of evidence
Chromatography answers how much and how clean. Mass spectrometry answers what. A retention-time match alone can be coincidental; a mass confirmation alone says nothing about purity. A certificate is worth having because it carries both.
Content claims are made against characterised reference standards, never against another submitted sample. That is the difference between saying a vial is 10.2 mg and saying it looks similar to the last one.
The full analyte list
Eleven analytes, method by method.
| Analyte | Method | Specification |
|---|---|---|
| Peptide Purity Chromatographic purity as area percent at the primary detection wavelength, reported against all resolved peaks. | HPLC-UV, gradient RP | ≥ 95.0% (area %) |
| Net Peptide Content Absolute mass of peptide recovered per vial, quantitated against a characterised reference standard. Confirms the vial holds what the label says. | HPLC-UV vs. reference standard | Not less than label claim |
| Identity Retention-time correspondence with an authentic reference standard under identical gradient conditions. | HPLC retention time | Matches reference standard |
| Arsenic (As) Elemental impurity screen aligned to the USP <232> limits for parenteral routes. | ICP-MS | NMT 1.5 ppm |
| Cadmium (Cd) | ICP-MS | NMT 0.5 ppm |
| Lead (Pb) | ICP-MS | NMT 1 ppm |
| Mercury (Hg) | ICP-MS | NMT 1.5 ppm |
| Chromium (Cr) | ICP-MS | NMT 10 ppm |
| Sterility Broad-range bacterial and fungal detection by amplification, reported alongside a growth-based confirmation. | Nucleic-acid amplification (PCR) | No growth detected |
| Endotoxin Bacterial endotoxin quantitation by kinetic chromogenic Limulus amebocyte lysate assay. | Kinetic chromogenic LAL | < 0.25 EU/mL |
| Fentanyl Presence Analysis Targeted screen for fentanyl and common analogues as an adulteration check on incoming material. | LC-MS/MS, targeted | Not detected |
Platforms
Instrumentation.
Each platform earns its place by answering a question the others cannot.
Reversed-phase chromatography
Gradient separation with diode-array detection. The workhorse for purity as area percent and for net content against a reference standard.
Liquid chromatography – mass spectrometry
Mass confirmation of the intended species and targeted detection of adulterants down to trace level.
Inductively coupled plasma mass spectrometry
Elemental impurity quantitation in parts per million after acid digestion of the sample as supplied.
Bacterial endotoxin test
Endotoxin quantitation in EU/mL, read kinetically against a standard curve with positive product controls.
Sterility by PCR
Broad-range bacterial and fungal detection, paired with a growth-based confirmation before a result is released.
Traceable comparators
Characterised comparators for every compound we report on. Identity and content claims are made against them, never against each other.
Reporting
What a specification actually promises.
A pass means the result met the limit printed beside it under the stated method, on the sample as received. It is not a statement about a different vial from the same lot, and it is not a statement about how the material was handled after it left us.
01Area percent purity
The share of total resolved peak area attributable to the target compound. Co-eluting species cannot be counted as impurities if the method does not resolve them, which is why gradient conditions matter.
02Net content
Absolute recovered mass per vial against a reference standard. This is the figure that catches underfilling, and the one most often missing from documents we are asked to check.
03Limits in ppm
Elemental results are printed with the method limit alongside, so a result of 0.03 ppm against a 1.5 ppm limit reads as what it is: comfortably clear, not merely “pass”.
Method questions
Ask before you ship.
If you need a specific method, a tighter limit, or an element outside the standard five, say so in the request. It is cheaper to agree the method before the sample arrives than to re-run it afterwards.