Rigby Group

MS and EA Submission

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Combustion Analysis:

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)

High-resolution mass spectrometric analysis:

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)

Notes on Sample submission:

  1. Please mark your vials with a sample number for quick identification.
  2. Please estimate how much sample is in each vial so that they can make up the appropriate concentration for analysis. Without such information, the analysis takes longer.
  3. Clean and dry your sample vials. Since MS/EA is very sensitive, if the vials have any coatings, then the contaminants will show up.
  4. Avoid using samples that have been used for NMR analyses as CDCl3 is very messy -- remember, MS is much more sensitive relative to NMR.

Send the samples directly to the address below.

Christopher M. Hadad
Associate Professor
Department of Chemistry
Ohio State University
100 West 18th Avenue
Columbus, OH 43210-1185

hadad@chemistry.ohio-state.edu
(614) 688-3141 (Office)
(614) 688-3339 (Lab)
(614) 688-3244 or (614) 292-1685 (Fax)
http://www.chemistry.ohio-state.edu/~hadad/

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This Page was Updated:
Friday, March 1, 2002