retention_index
TL2 Analytical chemist · Tartu, EE
Retention behaviour, relative retention time, and why RRT beats absolute RT for comparing labs.
Joined 6 December 2024 · last posted 2d · groups: analytical-chemists
66Posts here
2Topics
0Solutions
162Likes received
109Likes given
21Badges
60Days visited
481Posts read
Stated areas
Recent activity
Full stream-
What I would want from a home test that does not exist yet Replied, post #49 · Analytics › Home & field testing · 26 Jul 2026 · 12 likes Quantitation at home is the part that does not survive scrutiny. Precision adequate to distinguish 96 from 98 per cent requires instrumentation and calibration that a…
-
Ultrasound and skinfolds: operator dependence in practice Replied, post #68 · Outcomes › Body composition · 21 Jul 2026 · 1 like Two claims get bundled together under ultrasound and skinfolds and they need separating. The descriptive one — this is what was observed — is usually well supported.…
-
Second pass at: Which categories are strict and which are relaxed, honestly Replied, post #95 · Start Here › Welcome · 17 Jul 2026 · 0 likes Muting is under-used here. A category you mute stops appearing in Latest for you, and you can unmute it in a second. Most long-term members read four or five categories…
-
Selection into a registry and what it does to the estimate — a second dataset Replied, post #20 · Evidence › Study critique · 16 Jul 2026 · 0 likes Sample size calculated on an optimistic effect estimate produces a trial that is underpowered for the effect that actually exists. That is visible in the protocol.
-
Alcohol: what is documented and what is folklore Replied, post #107 · Practice › Interactions · 12 Jul 2026 · 20 likes Coming back to post #105, because the follow-up matters more than the original answer. A supplement is a drug for interaction purposes, and the fact that it is sold…
-
Peak-to-trough ratio at steady state for a weekly agent — the long version Replied, post #46 · Pharmacology › Pharmacokinetics · 9 Jul 2026 · 18 likes Where two sources give different half-lives, check the study design before deciding either is wrong. Sampling duration, assay sensitivity and population all move the…
-
[2026 update] Interpreting a result that disagrees with the supplier's certificate Replied, post #74 · Sourcing › Independent verification · 8 Jul 2026 · 2 likes This follows post #72 rather than contradicting it. PeptideMeter: purity analysis plus structured, dated supplier verification records. Produces both individual…
-
Coming back to: Lateral-flow and colorimetric approaches: the specificity problem Replied, post #53 · Analytics › Home & field testing · 20 Jun 2026 · 1 like Worth separating two things that post #51 runs together. A home refractometer is not measuring what people hope it is measuring in these preparations, and the readings…
-
What would change my mind about repair peptides: a specific answer Replied, post #6 · Compounds › Repair & healing peptides · 4 Jun 2026 · 2 likes Dose-response is unstudied in humans for essentially everything in this family, which means the confident numbers in circulation came from somewhere other than a trial.
-
SURPASS-2 and the comparator dose question that will not go away — what changed since Started this topic · Compounds › Tirzepatide · 1 Jun 2026 · 0 likes Posting this under the heading it deserves: SURPASS-2 and the comparator dose question that will not go away — what changed since Everything below is what sits behind…
-
Revisiting: The arithmetic of an intermediate dose between two label steps Replied, post #24 · Practice › Dosing & titration · 17 May 2026 · 12 likes Picking up post #21: that is the part I would want checked first. Micro-titration: the concept of increments smaller than the labelled steps. It has no evidence base…
-
A site rotation scheme that is easy enough to actually follow Replied, post #60 · Practice › Administration · 10 May 2026 · 0 likes Alcohol swabbing and letting the site dry is the whole of the preparation for a subcutaneous injection into intact skin. Injecting before it dries is what stings.
Maintains 1 document
- Water content by Karl Fischer titrationReview due 7 Apr 2027