A glossary of sourcing terms

Two documents can share a folder and still answer different questions. A specification says what your experiment will accept. A datasheet says what a manufacturer publishes about one product. Mix those questions and a reply can look complete while the salt form, the rotor, or the certificate stays blank. This page compares the pairs that cause that mix-up. The writing method they belong to is how to write a laboratory sourcing enquiry. A structured file goes through laboratory procurement.

Chemicals you will name by identity sit in the reagents and chemicals catalogue. University laboratories can also start from academic research. The quotation page and the contact page are the routes that take a written specification to a person. A larger study, with a statement of work rather than a single bottle, uses the same pairs and is set out in commissioning a sequencing or proteomics study.

The decision these pairs support

You are deciding which paper defines the requirement, and which paper is only evidence. The quotation can be checked only if you know whether you are holding a specification, a datasheet, a scope, a catalogue line, an acceptance test, or a brochure sentence. Read each pair as two questions. Keep a document that answers the other question, and do not let it replace the one you still need.

Specification and datasheet

A specification is your list. It names identity, performance, environment, quantity, documents, and the acceptance check, in lines a stranger can mark as met, met with an exception, or refused. It is written before a brand story is allowed to narrow it. A volumetric flask of a stated accuracy class, a polymerase with a stated unit definition, a plastic tube with a stated temperature rating: each of those is a line. A public method library such as protocols.io can show which line a protocol assumed. It does not replace the list.

A datasheet is the manufacturer's description of a product. It may give dimensions, a speed table, a purity statement, storage conditions, and warnings. It is evidence about that product. It is useful when you attach it and point to the row that meets one of your lines. It is a poor specification, because it was written to describe a catalogue item, and your experiment may need a certificate, a salt form, or a room condition the datasheet never mentions.

Worked comparison. You need a benchtop centrifuge that reaches a relative centrifugal force you name, with a rotor that accepts 1.5 mL tubes, at a laboratory temperature you state. That is the specification. The datasheet may show several rotors and a noise figure. You copy the rotor row that matches the tube, and you ask the quotation to confirm that row. You do not paste the whole datasheet and call it your requirement. If the datasheet assumes a cooler room than the one you have, the specification says so, and the quotation has to answer that line.

The branch when this control fails: a reply attaches a datasheet and answers none of your numbers. You write back and ask for a line-by-line response. You do not fill the gaps by assuming the most favourable row on the datasheet.

Quotation and proforma

A quotation is a reply to the specification. For each scientific line it should say that the offered item meets the line, meets it with a named exception, or does not meet it. Any commercial terms the seller states belong in that same reply. You read them on the document you receive and file them with the specification.

A proforma is a preliminary commercial document. Laboratories meet it when a finance office, a customs description, or a payment step asks for a formal list of goods before an order is final. A proforma can carry names and commercial conditions. It does not, by its name alone, show that anyone scored the salt form, the certificate, or the rotor.

Worked comparison. A proforma lists Tris buffer and a pack size. Your specification asked for Tris base, a stated purity, a certificate of analysis, and an explicit statement that the material is the base rather than the hydrochloride. The proforma has not answered those lines. Obtain a quotation that maps them, or keep the proforma as a commercial draft. Salt identity of that kind is the subject of preparing a buffer and checking pH.

The branch: if the only document you have is a proforma, ask which scientific lines it claims to answer. If the answer is none, keep the specification open and do not let the commercial draft close it.

Scope and catalogue line

A scope is the scientific job and its boundary: what is included, what is out of scope, and what decision the result may support. For a study, that scope is the statement of work. Commissioning it is a separate guide, linked above. A scope can mention many products and also work that is not a product, such as a data format or a sample-handling constraint.

A catalogue line is one product identity: a name, a pack, a quantity, and the performance you asked that product to meet. It is the right unit for a bottle, a box of tubes, or a rotor adapter. It is the wrong unit for a study. Buying the kit line does not commission the analysis, and commissioning the analysis does not identify the tube.

Worked comparison. The scope says: compare two extraction chemistries on twelve practice samples and report yield and a purity ratio the laboratory already measures. Out of scope: any claim about a biological effect in a cohort. Inside that scope sit catalogue lines for the two chemistry classes, for tubes, and for nuclease-controlled water. Each line can be quoted. The scope is what stops someone treating a successful tube order as a finished study.

The branch: if a reply quotes one catalogue line and is silent on the rest of the scope, mark the silent parts as unanswered. Do not let a single line stand in for the job.

Acceptance test and brochure claim

An acceptance test is the check you will do, or the document you will file, before the item is released for use. It is written in the specification. Examples that a laboratory can actually perform: the seal is intact; the lot characters on the container match the lot characters on the certificate; a temperature logger, if you required one, stayed inside the range you named; a pipette's calibration certificate cites a named procedure. NIST's laboratory metrology pages are a public reminder that a calibration claim points at a procedure and a record.

A brochure claim is an adjective. Ultrapure, high fidelity, nuclease-free, research grade, and robust all appear on brochures. Some of them can be turned into acceptance tests when a certificate states a method and a result. Until that happens, the adjective is not a line you can fail.

Worked comparison. A brochure says the water is nuclease-free. Your acceptance test says: the certificate names a nuclease assay, the lot on the certificate matches the container, and the laboratory will not release the bottle if either of those is missing. The brochure sentence can stay in the file as the manufacturer's wording. The acceptance test is what the receiver follows. If the certificate arrives without a lot, the branch is quarantine, not a quiet place on the shelf.

Equivalence and identical

Identical means the same identity where identity matters. For a chemical, that is the substance, the salt form, and the hydrate the recipe weighs. For a locked enzyme method, it is the formulation and the manufacturer's unit definition, because another maker's unit is a different assay. Identical is the right word when substituting would change the measurement even if the common name stayed the same.

Equivalent means the numbered performance lines are met, and the laboratory can run the test it wrote. A tube that fits the rotor, survives the stated speed, and has the sterile claim you asked for can be equivalent to a named tube even when the mould comes from another factory. Equivalence is a scientific allowance. It needs the lines and the test. A sentence that says "or equivalent" and then stops is an invitation to guess.

Worked comparison. You specify a hot-start DNA polymerase by the unit definition in the protocol you are following, because the magnesium and the antibody used for hot start are part of that method. You ask for that formulation. Separately, you specify filter tips by volume family, filter, and sterile claim, and you allow an equivalent that you will fit on the pipette before the box is released. The enzyme line is identical. The tip line is equivalent. Putting both words on both lines is how the wrong enzyme arrives with a perfectly acceptable tip.

The branch: if a reply offers an equivalent on a line you marked identical, that is an exception. Accept it in writing only if you are willing to change the method. Otherwise refuse that line and keep the rest.

When a pair is confused

The usual failure is a tidy file that cannot be scored. A datasheet, a proforma, a catalogue line, and a brochure can all be present while the specification is still missing. Nobody can then point to the hydrate, the lot match, or what the study may conclude.

The opposite failure copies every brochure adjective into the specification until no seller can answer. ISO 9001 is a public standard about documented information. Ask for the document that makes your line checkable, and leave the rest out.

A third failure is silent equivalence. The reply changes the salt, the accuracy class, or the unit definition and describes the change as a minor alternative. Record the exception, or refuse the line.

Research use, and safety that stays with the institution

These terms do not approve a biological risk. A quotation for a kit, a scope for a study, and a catalogue line for plasticware are purchasing documents. Containment, disinfection, and whether a material may be handled at all are decisions of the institution's biosafety arrangements. Biosafety basics for research benches is the cluster page for that separation. Nothing here is medical advice, a diagnostic claim, or a biosafety approval.

Reagents named in a specification are for the research use the laboratory has already defined. A brochure that wanders into clinical language does not convert a research enquiry into a clinical order. Leave that language out of the lines you ask a seller to answer.

Heat, humidity, and the line a datasheet skipped

Datasheets often assume the manufacturer's storage statement. Your specification should name the room you have when heat or humidity changes the item: a hot receiving dock, a humid store, an instrument room that is cooler than the dock. "Room temperature" on a datasheet is not a measurement of that dock. If moisture or heat can harm the item, the acceptance test includes the condition on arrival, and the storage line says where it will sit afterwards.

What the enquiry carries

Send the specification, not a stack of substitutes. For each line, say whether you need the identical formulation or an equivalent you will test. Ask the reply to map every line, and say which documents must arrive with the goods so the acceptance test can be run. State the scope in one or two sentences so a catalogue line is not mistaken for the whole job.

Place that file on the quotation page when you are requesting a quotation against selected lines, or use the contact page to send the specification. Academic research is the route aimed at university laboratories. Keep a copy of what you sent. The score you do later is the specification beside the reply, including every line the reply declined.