NMR Figure 4
Discovery begins with measurement
Figure 4: 597.59MHz 1H NMR spectra at 25C. A ding sherd (archaeological sample) from H31 at the site of Liangchengzhen and a modern pig bone from China with functional group assignment. The reported chemical shift values were referenced with the deuterated methanol peak at 3.34 ppm. The presence of pig residue was validated by comparing the 1H NMR spectrum of the total lipid extract of the sherd (blue) to the spectrum of a reference sample prepared from the bone of cooked pig (green). An excellent correspondence is observed between the two spectra which supports the results obtained through GC/MS. The assignment of the major set of signals that appear in the spectrum is shown, highlighting the observed proton in red. 1H chemical shift values for pig bone and pig pottery are detailed in Table 1. Many of the assignments were further confirmed by the use of a 2D 1H-1H TOCSY (see Figure 5). (Fig. 4 assigned by Vasantha Kumar, Ph.D.)