LL-37 5mg Vial

Description

The LL-37 5mg vial is supplied as a reagent: a thirty-seven residue cathelicidin derived peptide, lyophilized, sealed and assayed by lot. The fill weight is 5 mg of net peptide content. The powder is white to off-white. Nothing here is addressed to a person, because the material is not for human or veterinary consumption.

The same material is catalogued elsewhere as Cap18. The name comes from the two leucines at the N terminus and the length of the sequence, so for once the abbreviation is a description of the structure. The label on the LL-37 5mg vial carries the compound, the fill weight and the lot number, and that is the extent of it.

What the LL-37 5mg vial is

The table below is the standing description of the LL-37 5mg vial. Measured values live on the lot certificate.

Lyophilized powder, and the price per milligram of the LL-37 5mg vial

Freeze drying is how a peptide reaches you stable at ambient temperature. The solution is frozen solid, then the ice is pulled off under vacuum instead of being melted, so the water never passes through a liquid phase on the way out. What is left behind is a porous cake. In the vial it may sit as a flat disc, a loose dust, or a thin film part way up the glass. None of those appearances says anything about the contents. Fill weight and the assay figure do. Nothing about the LL-37 5mg vial is sold by volume.

How the per milligram figure is worked out

Milligram content is the unit the LL-37 5mg vial is sold in, because it is the only figure that makes two listings comparable. The per milligram figure is approximately $27.80 at the current price. It is the honest basis for comparison because it cancels out vial size. A vendor quoting only a bottle price is asking to be compared on the wrong axis. Compare the LL-37 5mg vial on that basis rather than on the price of the glass. The case is made at greater length in why price per milligram beats the price on the bottle.

The certificate of analysis for the LL-37 5mg vial

Certificates vary in layout and should not vary in content. Compound name, lot number, analysis date, HPLC purity with chromatogram, mass spectrometry identity, water content, laboratory identity and signature. Check the lot number against the vial, check the date, then read the figures. Documents that summarise results without showing the chromatogram are asking for more trust than they have earned. The certificate issued with the LL-37 5mg vial is specific to the lot and not to the product line.

The assay is performed by a contract laboratory unconnected to this business. Any lot that comes back below its stated milligram content is pulled from sale, and the certificate stays published on the results page with everything else instead of quietly disappearing. Stock is withdrawn from sale where the certificate for the LL-37 5mg vial does not support the figures here. See how to read a certificate of analysis and check the lab before you check the numbers.

Behind the figures

Karl Fischer titration gives the water content, stated as a percentage. A lyophilized cake is never bone dry, and the point of measuring is to know by how much it misses. Moisture that stayed behind in the cake is moisture that can take the peptide apart slowly in storage, and it is also weight that is not peptide. The same methods are run on the LL-37 5mg vial as on every other lot on this shelf, and formulae and expected masses for compounds of this class can be checked through PubMed.

Why the name is inconsistent, and how to store the LL-37 5mg vial

Abbreviations here are inherited rather than designed. They come from the groups that first made a compound, from ingredient registers, from development programmes and from vendors, so two listings can look different and be identical. Where an abbreviation expands into a statement about what a compound does, the abbreviation is what appears here, in the title, the web address, the image description and the text alike. The catalogue name carried by this vial is the one the trade uses, and a trade name is not an identifier.

Keep the vial sealed, cold and dark. Lyophilized material of this class is normally held at 2 to 8 degrees Celsius for short periods and at minus 20 degrees Celsius or below for longer ones, and the window for the lot is on this listing. Keep the certificate with the vial, since the lot number is the only thing joining the two.

Research use only, stated plainly

Research use only, not for human or veterinary consumption. That sentence is a description of what is being sold and not a disclaimer appended to something else. There is accordingly no dose, no cycle, no route of administration and no reconstitution guidance anywhere on this page, and the omission is the policy rather than a gap in the copy. No part of this page describes a use for this material in a person or an animal. Bacteriostatic water, sterile diluents and syringes are stocked separately rather than sold as a set with the vial.

The limits of that sentence need stating. A research use only line describes what is sold, it is not a shield, and the enforcement record shows whole product pages being read rather than disclaimers alone. See research use only is not a legal strategy.

Every figure quoted here comes from the document linked above, and older certificates are kept rather than retired. That is the whole of the claim being made. This item sits on the repair and recovery shelf, inside the research peptide catalogue, and every certificate we hold is on the lab results page.