(copied from ReO) Reagents are distinguished from devices/instruments that also serve as facilitators in scientific techniques by the fact that reagents are chemical or biological in nature and necessarily participate in or have parts that participate in some chemical interaction or reaction during their intended participation in some technique. By contrast, devices do not participate in a chemical reaction/interaction during the technique. Reagents are distinguished from study subjects/evaluants in that study subjects and evaluants are that about which conclusions are drawn and knowledge is sought in an investigation - while reagents, by definition, are not. It should be noted, however, that reagent and study subject/evaluant roles can be borne by instances of the same type of material entity - but a given instance can only realize one of these roles in the execution of a given assay. For example, taq polymerase can bear a reagent role or an evaluant role. In a DNA sequencing assay aimed at generating sequence data about some plasmid, the reagent role of the taq polymerase is realized. In an assay to evaluate the quality of the taq polymerase itself, the evaluant/study subject role of the taq is realized, but not the reagent role since the taq is the subject about which data is generated. In regard to the statement that reagents are 'distinct' from the specified outputs of a technique: note that a reagent may be incorporated into a material output of a technique, as long as the IDENTITY of this output is distinct from that of the bearer of the reagent role. For example, dNTPs input into a PCR are reagents that become part of the material output of this technique, but this output has a new identity (ie that of a 'nucleic acid molecule') that is distinct from the identity of the dNTPs that comprise it. Similarly, a biotin molecule input into a cell labeling technique are reagents that become part of the specified output, but the identity of the output is that of some modified cell specimen which shares identity with the input unmodified cell specimen, and not with the biotin label. Thus, we see that an important criteria of 'reagent-ness' is that it is a facilitator, and not the primary focus of an investigation or material processing technique (ie not the specified subject/evaluant about which knowledge is sought, or the specified output material of the technique).

PERSON:Matthew Brush

2013-6-5 MHB: Clarifications regarding the distinction between reagetns and devices were made at the May 2013 Philly Workshop. Reagents are distinguished from devices that also participate in scientific techniques by the fact that reagents are chemical or biological in nature and necessarily participate in some chemical interaction or reaction during the realization of their experimental role. By contrast, devices do not participate in such chemical reactions/interactions. Note that there are cases where devices use reagent components during their operation, where the reagent-device distinction is less clear. For examples, see editor note on OBI:device.

reagent

http://purl.obolibrary.org/obo/IAO_0000120

PERSON:Matthew Brush