dalton2
(ˈdɔːltən)
Also Dalton.
[f. the name of John Dalton (see Daltonian a. and n.).]
A name for the atomic mass unit (see atomic a. and n. A. 1), used chiefly in Biochem.; freq. used as a dimensionless unit of molecular weight.
| 1938 C. M. Beadnell Dict. Sci. Terms 65/1 Dalton, mass unit, being the 1/16 of mass of O atom. 1967 New Scientist 27 Apr. 196/1 The size in molecular weight units was about five million daltons—in other words each molecule of DNA weighed as much as five million atoms of hydrogen. 1969 Nature 11 Oct. 150/1 All DNAs were sheared to a single-stranded molecular weight of about 400,000 Daltons by passage through a French pressure cell. 1970 Ibid. 28 Nov. 889/2 Thus it would be correct to write..‘the molecular mass of protein X is 250,000 [read 25,000] daltons’; or ‘the relative molecular mass (that is, molecular weight) of protein X is 25,000’... It would, however, be incorrect to say: ‘the molecular weight of protein X is 25,000 daltons’, for the dalton is a unit of mass, and molecular weight is dimensionless. |