A module leader drafts a practical around one pre-mixed vial, submits a requisition through the university’s procurement system, and receives a courteous but firm refusal. It looks like an inconvenience at the wrong end of term. In practice it is the point where a supplier’s compliance position, its analytical documentation and the realities of an undergraduate bench meet — and the fixed blend is usually the format that loses. The Compliance Line That a Pre-Mixed Vial Crosses Research Sciences, the UK supplier trading at researchsciences.co.uk, states plainly in its FAQs that it does not supply blended peptides — Ipamorelin combined with CJC-1295 is the example given — and that researchers…