Peptide Custom Synthesis Request Checklist for Procurement Teams

A peptide custom synthesis request checklist for procurement helps buyers submit complete inquiries the first time, reducing back-and-forth and quote revisions. This article focuses on what information to assemble before contacting a manufacturer and how to frame questions so responses are comparable. It does not provide dosing guidance, weight-loss instructions, or disease-treatment claims, and it does not assert any supplier certification or capability. The checklist is a communication tool, not a specification document, and should be adapted to your organization's internal requirements.

Start with the sequence itself, written in single-letter code, plus any non-natural amino acids spelled out clearly. Include the desired N-terminus and C-terminus forms, such as acetylation or amidation, and the intended salt form if you have one. If the sequence is confidential, ask about confidentiality agreements before sending it. Ambiguity here is the most common cause of misquotes, so have a second reviewer check the sequence against your internal records before submission.

Modifications deserve their own section. Cyclization, disulfide bonds, labeling with fluorescent or affinity tags, pegylation, and unusual side-chain protecting groups all change synthetic difficulty and analytical requirements. For each modification, state the intended position and whether alternatives are acceptable. Ask the supplier to describe how they confirm the modification was incorporated, for example by mass spectrometry or sequencing. Avoid assuming a modification is routine; ask directly and request a written response.

Purity and analytical expectations should be stated explicitly. Specify the purity range you need, the method you expect to be used to demonstrate it, and whether you need a certificate of analysis with specific data. If your downstream work requires additional testing such as amino acid analysis, water content, or counterion identity, list it. Procurement should also ask which tests are included in the base quote and which are priced separately, so total cost comparisons are meaningful across suppliers.

Quantity and delivery format matter as much as chemistry. State the mass required, whether you need a single batch or multiple aliquots, and the preferred packaging, such as sealed vials under inert gas. If you need the material shipped under specific temperature conditions, say so and ask how the supplier validates that shipping configuration. These details affect both price and lead time, and clarifying them early prevents rework after the order is placed.