ISO_NWIPs-for-Ballot

ISO/NP

798 799

8

Analysis

8.1 General 800 Signals for the reference material for qNMR and the target analyte are observed on the 1 H qNMR 801 spectrum of the sample solution, and are quantified according to the internal standard method. 802 Measurement of the signal areas on the 1 H qNMR spectra is performed with data processing software 803 which is either supplied with the system or installed onto the system later. For such measurement, 804 select the appropriate settings according to the shape of the signals. Because of the Lorentzian shape of 805 NMR signals, this should ideally cover a range of ± seventy six times the FWHM of each integrated peak. 806 If the peak is a complex multiplet an integration range of ± 30 Hz from the outermost 13 C satellite is 807 usually sufficient. When using third party data processing software that is installed onto the system 808 later, refer to the specified procedures established by the manufacturer to ensure that the software 809 provides the correct results [see ref. 19]. 810 811 8.2 Calculation 812 The content of the target analyte ( P i ) of signal i is calculated using Formula (9). 813 Adequately separated signals are generally used for quantitative analysis, but in cases where the signals 814 from various functional groups are in close proximity and cannot be isolated and analysed separately, 815 the interval may be regarded as a single signal segment to determine the signal area. In this case, the 816 total number of protons observed in the range of integration is used for the number of protons ( N i ) for 817 the analyte signal i. 818 s a s s i i s s i i P m m M M N N S S P 819 where 820 P i is the content expressed by signal i of the analyte; 821 P s is the purity of the reference material for qNMR; 822 S i is the signal area of the analyte signal i; 823 S s is the area of the reference material for qNMR; 824 N i is the number of protons corresponding to analyte signal i; 825 N s is the number of protons corresponding to the reference material for qNMR; 826 M i is the molar mass of the analyte; 827 M s is the molar mass of the reference material for qNMR; 828 m a is the mass of the sample; 829 m s is the mass of the reference material for qNMR. 830 831 (9)

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