October 9, 2026
How third-party testing actually works
An independent lab receives the sample, runs purity and identity checks on instruments it owns, and signs a report. What happens between the sample bag and the signed page.
4 min read
Testing
How a result is produced: what an accredited laboratory does with a sample, which questions each test answers, and what has to be true of a method before its numbers mean anything.
9 entries
Newest firstJuly 14, 2026
Why retention samples matter
A small, sealed portion of each batch is kept for years after release. It is the only way to test the same material again when a question comes later.
4 min read
July 1, 2026
When a result is out of specification
An out-of-specification result starts an investigation, not a retest. The first question is whether the lab made an error, and the answer is documented either way.
4 min read
June 16, 2026
Stability testing in plain terms
Stability studies measure how a material changes over time under controlled storage. They are where retest dates and expiry dates come from.
4 min read
June 2, 2026
What method validation means
Validation is documented evidence that an analytical procedure measures what it claims to, accurately and repeatably, across the range it will be used for.
4 min read
May 15, 2026
Sample integrity from collection to instrument
A result describes the sample the instrument received. Everything between the container and the injection decides whether that sample still represents the lot.
4 min read
May 1, 2026
A plain-language look at HPLC
A pump, a packed column, a detector and a reference standard. What a chromatogram shows, how a peak becomes a number, and what the method cannot see.
4 min read
April 17, 2026
Identity versus purity: two different questions
Identity asks whether the material is what the label says. Purity asks how much of it is. A result can pass one and fail the other.
4 min read
April 3, 2026
What an accredited lab actually does
Accreditation is an outside body's finding that a lab can do specific tests competently. It covers a listed scope, not the lab as a whole.
4 min read