What batch documentation should tell you

Research-grade material is only as good as the data released with it. Four documents carry most of the weight. Identity: mass spectrometry confirming the molecular weight expected for the declared sequence. Purity: reverse-phase HPLC quantifying the main peak and reporting related impurities, with the method stated. Sterility and endotoxin: applicable to some formats and not others, and it should be obvious which. Handling: storage temperature, reconstitution guidance and stability expectations. Two habits separate serious suppliers from the rest. Documentation is tied to the specific batch you receive rather than a representative sample, and where a test does not apply to a format, that is stated plainly instead of implied.