Services and Fees
Price subject to change based on project specifications. Contact us for services and fees not listed below.
Mass Spectrometry Core Equipment
- Applied Biosystems Voyager-DE STR MALDI-TOF
- Applied Biosystems Voyager MALDI-TOF
- Thermo LTQ XL LC-MS Mass Spectrometer
- Thermo LTQ XL LC-MS/MS Mass Spectrometer
- Thermo LTQ XL LC-MS/MS Mass Spectrometer with capillary LC system
Quality Control
Data quality is ensured through the use of appropriate internal and external standards. The MALDI-TOF mass spectrometers are calibrated with external standards that vary depending on the analyte molecular weight. This results in the best calibration for the most accurate mass assignments. Samples that have been trypsin digested are internally recalibrated from observed trypsin autolysis fragments. The electrospray mass spectrometers are calibrated using polyalanine which allows for even distribution of multiple mass peaks. A variety of search engines, for protein identification from mass fingerprinting and for interpretation of MS/MS spectra, are available each of which generates its own statistics. The choice of database searching software to be applied is optional to investigators and discussion of this matter is encouraged with our technical support team.
Mass Spectrometry Sample Preparation Guidelines
Prior to sending samples, investigators are recommended to contact the facility to discuss the required analysis. This is necessary to ensure that the most efficient and cost-effective analytical methods are employed. Samples are normally analyzed in the order of their receipt, but special arrangements can be made for unstable samples.
A sample submission form should accompany each set of samples
General guidelines for sample preparation:
When preparing samples for mass spectrometric analysis, it is best to limit sample manipulations. When dealing with solution samples, never bring the sample to complete dryness. Salts and detergents will interfere with MS analysis of solution samples. Based on extensive studies, we have found that SDS-PAGE or 2D IEF-SDS-PAGE is the best method for recovery of low quantities of protein.
- The sample should be dissolved in pure water or shipped completely dry if possible. Try to avoid sending samples in high ionic strength buffers as this may interfere buffers, such as PBS, are well known for suppressing the ionization process and should be avoided if possible.
- If the sample is shipped in solution containing any salt, please provide an estimate of the salt concentration possible. Also, providing a list of the salts and buffers that might be present in the solution is also extremely helpful.
- Any amount of sample can be submitted for analysis. Due to the fact the ionization process and detector sensitivity are sample dependent, it is rather difficult to specify a minimum amount of sample necessary for analysis. The general rule of thumb is, "The more the better".
Sample amount recommendation:
Sample Requirements and Shipping:
Please provide amounts of 1 to 3 µgs and higher per oligonucletide, peptide or protein in lyophylized as a dry powder form. If possible ship sample frozen in aqueous solution containing volatile buffers. If this is not possible an additional sample handling step may be needed.
LC MS/MS
- Please provide estimated or exact molecular mass for your sample if known.
- Alternatively, provide the molecular range in which the molecular mass is expected.
- Provide sample amounts of 1 to 3 µgs or more.
- For protein identification via LC-MS/MS coomassie blue stained and digestion compatible silver stained protein bands are appropriate.
- LC-MS/MS allows analysis of complex peptide and protein mixtures. Call for info for more details.
MALDI-MS
- Suitable for intact protein mass analysis.
- Analysis of DIGE protein spot digestion is possible.
- A variety of biomolecules can be analyzed including oligosaccharides, and gangliosides.
- Please provide information regarding the sample. This includes information such as sample type (peptide, protein, etc.), expected molecular weight, purity, etc.
- Radiolabeled samples may not be submitted for mass analysis.
Tips:
Protein/peptide solutions in 10 μM volatile buffers can sometimes be analyzed directly while samples with higher salt concentrations require prior C18 or C4 ZipTip desalting.