TB-500 Fragment 17-23 10mg Vial

Description

The TB-500 Fragment 17-23 10mg vial is a laboratory reference material and nothing else. The compound is the seven residue 17 to 23 segment of thymosin beta-4. The fill weight is 10 mg of net peptide content. Appearance is white to off-white, sealed under vacuum, with the lot number printed on the label. It is not a food, not a drug, and not for human or veterinary consumption.

It is catalogued separately from the longer fragment, and the two are easy to confuse on a listing and impossible to confuse on a mass spectrum. The label on the TB-500 Fragment 17-23 10mg vial carries the compound, the fill weight and the lot number, and that is the extent of it.

Contents of the TB-500 Fragment 17-23 10mg vial

The table below is the standing description of the TB-500 Fragment 17-23 10mg vial. Measured values live on the lot certificate.

The format, the fill weight and the milligram arithmetic

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 TB-500 Fragment 17-23 10mg vial is sold by volume.

How the per milligram figure is worked out

Milligram content is the unit the TB-500 Fragment 17-23 10mg vial is sold in, because it is the only figure that makes two listings comparable. The quotient is close to $7.90 per milligram. Keep two things in view when you use it: the fill weight it was divided by, and the assay percentage from the certificate, because the second tells you how much of that fill is the named compound. Compare the TB-500 Fragment 17-23 10mg 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.

Reading the certificate for this lot

The document issued with each lot states the compound, the lot number, the date of analysis, the purity percentage from HPLC, the identity confirmation from mass spectrometry and the water content from titration, and it names the laboratory that produced those results. It is one page. Read all of it, because the figures a vendor chooses to quote are rarely the complete set. The certificate issued with the TB-500 Fragment 17-23 10mg vial is specific to the lot and not to the product line.

Assays are run by an outside contract laboratory rather than in house. Independence of that kind matters, and it has a limit: the figure still depends on the sample that was submitted, which is why lot by lot testing rather than periodic testing is the part that matters. Stock is withdrawn from sale where the certificate for the TB-500 Fragment 17-23 10mg vial does not support the figures here. See how to read a certificate of analysis and check the lab before you check the numbers.

Purity, identity and moisture are three different measurements

HPLC provides the purity percentage. The method resolves a mixture into its parts on a column and the detector reports them as peaks whose areas are integrated. Purity is the main peak over the sum of all peaks. Because it is a ratio, two lots can share a purity figure and still differ in fill weight, which is why both numbers are published and neither substitutes for the other. The same methods are run on the TB-500 Fragment 17-23 10mg vial as on every other lot on this shelf, and formulae and expected masses for compounds of this class can be checked through the European Medicines Agency.

Naming, abbreviations and storage

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. Several abbreviations on this shelf unpack into descriptions of activity. They are not unpacked here, and where a compound cannot be described without that, only its measurable properties are described. The catalogue name carried by the TB-500 Fragment 17-23 10mg vial is the one the trade uses, and a trade name is not an identifier.

Storage is the usual practice for dry peptide material: sealed, refrigerated at 2 to 8 degrees Celsius over short intervals, frozen at minus 20 degrees Celsius or colder over long ones. Avoid moving it in and out of the cold repeatedly, because moisture condenses on cold glass. Keep the certificate with the TB-500 Fragment 17-23 10mg vial, since the lot number is the only thing joining the two.

Research use only, and what this page will not tell you

Sold to qualified purchasers for laboratory research only. Not for human or veterinary use. The page carries no dosing information, no protocol, no administration instructions and no account of physiological activity, because publishing any of those would be describing a use this material is not sold for. We will not supply them privately either. 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.

A research use only statement is not a legal strategy and is not treated as one here. Warning letters in this area turned on what the rest of the page said, not on whether a disclaimer was present. See research use only is not a legal strategy.

Lots that failed their own stated figures are kept rather than deleted, which is the point of an archive as against a highlight reel. 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.