Charge states and deconvolution, and why a correct mass says nothing about purity.
Mass spectrometry measures ions according to their mass-to-charge ratio. Charge states and deconvolution can help a laboratory compare an observed molecular mass with an expected mass. A matching mass supports identity under the method, but it does not measure how much of the sample is the target material.
Purity and identity should stay separate when reading a certificate. HPLC can describe the composition of detected chromatographic signal, while MS can provide mass confirmation. A correct mass says nothing by itself about purity, sterility, endotoxin, or the total amount of material in the container.