MS and EA Submission
The cost is $10 per sample for C, H and N, and they try to do replicate runs.
They can email you the results or send a package by DHL overnight delivery (especially if you want your samples returned).
You must take a 1H NMR of the sample to ensure purity prior to sending it out. Doing otherwise wastes significant money and other people's time.
Please provide between 2 and 10 mg of each sample, so that they can perform replicate analyses.
Get the combustion form (pdf)
The cost per sample is also $10.
Either electron impact (EI) or electrospray ionization (ESI) will be used. In particular, ESI would is practical for your organic and peptidic samples. They can handle m/z ratios under about 1600 amu with high resolution capability.
They usually spray solutions of your sample doped with a small quantity of NaCl in THF, MeOH, CH2Cl2 or water (and usually in mixtures of solvents) depending on solubility. They use (in most cases) 50/50 THF/MeOH solution with a small amount of added NaCl.
With these ionization conditions, they detect predominantly the Na+ adduct of the species M, and usually denoted as [M + Na]+ in the spectra. In some cases, if your sample has acidic protons or acidity is enhanced upon coordination with Na+, then you might see the protonated species [M + H]+ as well.
Get the Mass Spec. form (pdf)
This Page was Updated:
Friday, March 1, 2002