Method for heteronuclear quantitative determination by NMR spectroscopy, reference substances therefor and method for determining the degree of deuteration of a deuterated compound
Disclosed are a method for the quantitative determination of an analyte in a test item using a NMR spectrometer, wherein the deuterated solvent used to dissolve the analyte is used as the internal standard, and specific reference substances for use in the method according to the invention. Further described is a method for determining the degree of deuteration of a deuterated compound.
1. A method for determining the degree of deuteration of a first deuterated compound, the method comprises the steps:
preparing a mixture of the first deuterated compound and a second deuterated compound whose degree of deuteration is known, so that both deuterated compounds are dissolved;
generating a 1 H NMR spectrum from the mixture and determining the integrals of at least one peak of each of the two deuterated compounds;
generating a 2 H NMR spectrum from the mixture and determining the integrals of the same peaks;
calculating the degree of deuteration of the first deuterated compound using the determined integral values and the known degree of deuteration of the second deuterated compound by means of equation (4)
{ D} Vb1 =100−({ H} Vb2 ×(Int H Vb2 /Int D Vb2 )/(Int H Vb1 /Int D Vb1 ) (4)
wherein:
{D}V b1 =degree of deuteration of the first deuterated compound,
{H}V b2 =degree of protonation of the second deuterated compound,
IntH Vb1 =Integral of a peak of the first deuterated compound in the 1 H NMR spectrum,
IntD Vb1 =Integral of the same peak of the first deuterated compound in the 2 H NMR spectrum,
IntH Vb2 =Integral of a peak of the second deuterated compound in the 1 H NMR spectrum, and
IntD Vb2 =Integral of the same peak of the second deuterated compound in the 2 H NMR spectrum.
2. The method of claim 1 , wherein at least one of the first and second deuterated compounds is a deuterated solvent for NMR spectroscopy.