Questions, answered.
Short answers, grouped by topic.
About HK Analytical
How do I know whether a report’s client is linked to you?
Every report says so on page one: “No link to HK Analytical” or “Affiliated client”. The statement is part of the signed record.
Tests and results
What does a standard test include?
Identity by LC-MS: the measured mass against the expected mass. Purity by HPLC-UV: the main peak’s share of all peaks. Content: mg of the peptide per vial, against a reference standard.
Why mass spectrometry for identity?
Different peptides can leave the column at nearly the same time, so retention time alone cannot always tell them apart. The mass shows which molecule is there.
What does “purity” mean on a report?
The share of UV-absorbing material, at the stated wavelength, that is the target peptide. It does not measure water, salts, endotoxin, microbes or metals. High purity does not mean a vial is sterile or safe.
Is the mg on the report net peptide or total powder?
The report always states the basis. Free base means the peptide itself, without salt or water. Results based on total powder read higher.
Why can your result differ from another lab’s?
Labs use different columns, reference standards, calculation bases and sample preparation, and vials in a batch differ. Our reports state method, basis and uncertainty, so you can compare like with like.
How accurate are your numbers?
Every measured value carries its expanded uncertainty (k = 2), or says why none is stated. We round to match it.
Do reports include the chromatogram and mass spectrum?
Yes, for identity and purity. Every result comes with the raw data behind it, not only a number.
Can you tell which GLP-1 is in a vial without being told?
Yes. Choose the blind GLP-1 test. We report which peptide from the method’s list is present, or a mix, and how much.
Do I have to tell you the label amount?
No. Choose “label withheld” in the quote. The analysts see the claim only after the results are final.
Safety tests
What is the difference between endotoxin and sterility?
Endotoxin is a fever-causing substance from bacterial cell walls. It can be present when no bacteria are alive. Sterility asks whether live microbes grow from the sample. They are separate tests, and each needs its own sample.
Do you report the actual endotoxin number?
Yes: EU per vial and EU per mg, with the method, the limit of quantitation and the spike-recovery check. Below the limit we print “less than” the limit.
Is your sterility test the 14-day USP <71> test?
Yes. It takes at least 14 days after we receive the sample.
Which extra tests do I need?
It depends on your research. Endotoxin and sterility answer questions about contamination. Metals and solvents come from manufacturing. TFA is a salt left from synthesis. Each test page says what the test can and cannot tell you.
Samples, ordering and privacy
How much does testing cost?
Prices are on request. The quote form asks for everything we need to price your tests.
How many vials do I need to send?
Your quote lists the exact number. Sterility and endotoxin need their own unopened vials.
What do you keep about me? Can I stay anonymous?
We need an email address and a country. A name is optional. We never need your home address: reports are online.
Whose name goes on the report?
The name you choose. The report also states whether you have any link to HK Analytical, and your role, for example buyer or seller.
Can I keep results private?
Yes. Reports are private by default. Anyone you give the link, or the ID and key, can open it. No one else can find it.
Verification
How do I check that an HK Analytical report is real?
Scan the QR code, or enter the report ID and key at hkanalytical.com/verify. The page shows the report’s status and the fingerprint of the PDF we issued. If the numbers or the fingerprint differ, the copy you have was changed.
Why does the report show a vial photo?
We take it when the sample arrives, so you can compare cap, fill and lot with your own vial. We never use photos sent by clients.
Can a seller use one report for many products or shops?
No. One report covers one sample from one client. It tells you about the vial we tested, not that your vial came from the same batch.
Does a report prove my vial is good?
No. It shows what we measured in the sample we received. Check that lot, cap and fill match. For the strongest evidence, test your own vial or join a group test.
What do “superseded” and “withdrawn” mean?
A correction is a new version. The old one stays visible, marked superseded, with the reason. Withdrawn means a report should no longer be used; the reason is shown. We never delete a report.
Group tests
How do group tests work?
Several buyers share the cost of testing a batch. One organiser deals with us, and every member can check the result.
How many vials should a group test?
One vial tells you about that vial. Three or more from the same batch show how much vials differ.
Can members stay anonymous?
Yes. We deal only with the organiser. Members do not need to give us their names.
Vendors
Can a vendor approve or change results?
No. A client can keep a report private. No one can edit a result; a correction is always a new version.
Do you white-label reports?
No. Every report carries the HK Analytical name, its verification link and the client relationship statement.
Disputes and limits
Can you tell me whether to use a product, or how much?
No. We report measurements only. We do not give medical or dosing advice.