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Methods
How to judge any supplier, including us.
Most of what goes wrong in this category is invisible if you only read the purity figure. These five guides explain what the numbers mean, what they leave out, and which questions separate a supplier who measures things from one who prints them. They contain no dosing, reconstitution or handling guidance.
The document most people scroll past
How to read a certificate of analysis
A certificate of analysis is not proof. It is a claim about a claim — and whether it means anything depends on four things you can check in about ninety seconds.
A ratio and an amount are different questions
Why net content fails more often than purity
A vial can be 99% pure and contain half the peptide on the label. Purity cannot detect that, because purity is a proportion of what is present, not a measure of how much is present.
The most-quoted number in the category
What HPLC measures, and what it cannot see
Reversed-phase HPLC is a separation technique with a detector attached. Understanding what the detector responds to explains most of what a purity figure can and cannot tell you.
Why the number on the vial is not the mass in the vial
Free base, salt, and what you are paying for
Almost every synthetic peptide is supplied as a salt, which means the powder in the vial weighs more than the peptide in it. Whether a vendor accounts for that is one of the quicker ways to judge them.
What the cold chain is actually protecting against
Storage and stability of the sealed vial
Lyophilisation exists because peptides in solution degrade. Understanding the mechanisms explains why storage conditions are specific rather than cautious — and where the published knowledge runs out.
All products are supplied for laboratory research use only — not for human or veterinary use.