Methods and quality
How we make a result, state its limits and keep reports honest.
01
How we measure.
Three techniques. Three questions.
- LC-MS
Identity
Which molecule is there, by its mass.
- HPLC-UV
Purity
The main peak’s share of the UV signal.
- quantitative HPLC
Content
mg per vial, against a reference standard.
02
Identity levels.
Never from retention time alone. Each report prints the level its evidence reaches.
- L0 Retention time only Never reported as identity
- L1 Retention time and UV spectrum Supporting evidence only
- L2 Intact mass, two or more charge states Minimum for “consistent with”
- L3 Accurate mass, ppm error, isotope fit Adds the error in ppm
- L4 L3 and MS/MS fragments Adds sequence coverage
03
Uncertainty, stated.
Every measured value carries its expanded uncertainty (k = 2). A verdict needs a stated specification.
format
10.34 ± 0.41 mg (k = 2) : digits match the uncertainty.
10.3417 mg digits the method cannot see
04
No edits after release.
A correction is a new version that names the old one and says why. Nothing is deleted.
05
Conflicts of interest and disclosure.
Every report states how the client is related to us. The statement is inside the signed record: removing it breaks the signature.
No link to HK Analytical. The client has no ownership, staff, funding, family or commercial link to HK Analytical, other than paying for this test.
Affiliated client. The link in words, its type, the basis for the statement, and who checked it and when.
What counts as a link
A link with us, our owners or our staff, held by the client or anyone who controls the client.
How it is decided
- 01 The client declares any link when requesting a quote.
- 02 The statement is checked before the report is issued. The checker is named in the record.
- 03 If in doubt, the report says affiliated.
For every client
- No client can approve, change, soften or delay a result.
- One report covers one sample from one client.
- No white-label reports. Every report carries our name, its verification link and the relationship statement.
- A false declaration withdraws the affected reports. They are reissued with the correct statement.
The details.
Purity, content and label claim
- Purity
- % area
- A share of the UV signal. Not an amount.
- Content
- mg per vial
- An amount, measured, with its basis and uncertainty.
- Label claim
- client-supplied
- What the label says. Never used as a result.
Decision rules
“Conforms” only against a stated specification and a rule agreed before testing. Otherwise: “Reported, no specification applied”.
- Simple acceptance
- Conforms when the value is inside the limit. Near the limit, up to about 50 % risk of a wrong call.
- Guarded acceptance
- Conforms only when inside the limit by at least U (k = 2). At most about 2.5 % risk; between the bands, inconclusive.
- Qualitative criteria
- Conforms when every acceptance criterion of the method is met: identity, sterility, screens.
Measured data only
Every value comes from our analysis of your sample. A test we did not run says “Not tested”. Client-supplied fields are marked.
A second person checks every report
An analyst runs the tests. A second person reviews the raw data and the report before release.
Reference standards
Content is measured against a reference standard. The report names its source and lot, or marks the result as an estimate.
Complaints and disputes
Think a report is wrong, or see one with our name that does not match our site? Tell us, with the report ID. You do not need the key. If a report changes, we issue a new version with the reason.
Data and privacy
No cookies, no trackers. Form entries and reports are stored with Cloudflare, our host. Reports are private by default.