Research Article
Characterization and Uncertainty Assessment of a Certified Reference Material of Chloramphenicol in Methanol (GBW(E)082557)
Figure 1
The H-NMR spectra of (a) internal standard (ethyl paraben and methanol-D4) and (b) sample solution (chloramphenicol, ethyl paraben, and methanol-D4).
(a) Ethyl paraben |
(b) Ethyl paraben + chloramphenicol |