However, using the arithmetic mean as a molecular mass reference assured that the reported concentration values were within 15% of the actual concentrations, regardless of the relative distribution of the three curcuminoids within the measured sample.
Reserpine (20 μM) was used as internal mass reference for DI-ESI-MS.
Our PPDB is a unique resource for the plant community and complements other plant proteomics resources, such as Promex, a mass spectral reference database for proteins and protein phosphorylation sites [76], SUBA a database for Arabidopsis protein localization [12], as well as databases specialized in other organelles, such as peroxisomes [77].
Peptides with less-than-significant Mascot score were thoroughly inspected, considering the correlation of peptide basicity with SCX fraction numbers, presence of characteristic high-energy CID fragments, and accurate mass measurements through internal calibration of the MS spectra using the masses of confidently identified peptides as internal mass references.
16O1H− and 31P− ions were detected with an EM, using 31P− as a reference mass.
On the other hand, various systematic contributions, e.g., the air buoyancy correction, balance parameters, molecular masses, and the purity of the reference (expressed as a mass fraction), were taken into account.
We also developed total lean mass versus height and sub-total BMC versus lean mass reference curves for children, as suggested by the ISCD in its latest Official Positions Statement for Pediatric DXA (see www.iscd.org).org
As well as singular reference, there is plural reference (e.g., 'The gerbils in the pet store') and mass reference (e.g., 'the water in Lake Michigan').
This paper describes an improved hydrometer calibration method using a ring type sinker as a reference standard mass.
