CMSF Frequently Asked Questions

General submission requirements

How do I submit a sample?

To submit a small molecule sample to the CMSF, fill out an online submission form. Provide as much information as you can. Following submission of the form, clearly label your sample with the reference number provided in the confirmation email and deposit the sample in the drop-off bag outside room 41 Chemistry. If you are sending samples from outside the University, please contact us regarding proper procedures. Proteomics samples are still accepted with the paper sample submission form, but will also be moving to an online system in the near future.

Where can I submit my sample?

If you are on campus, samples can be dropped off in the drop-off bag outside room 41 Chemistry. Please do not enter the CMSF to submit samples. If you are submitting a sample from outside Texas A&M University, please contact us and use the express shipping address provided to send your samples.

How can I get an account with CMSF?

If you are located on campus, you can use your department account number. However, if you are sending a sample from outside Texas A&M University and it is your first time, we need you to fill out the customer information form to create an account with us. Return the completed form to us or to the email or fax number provided on the form. Once you open an account with us, you can generate a PO number to subsequently use the facility. If you need further assistance please contact us.

Can I submit a sample from outside Texas A&M University?

We accept samples from other universities, government or private institutions. However, we give priority to samples submitted from within the TAMU research community. See fee structure for samples submitted from other institutions.

If you are submitting samples for the first time, please fill out the customer information form and return it to us by email or fax. Once you open an account with us, you can use a PO number to subsequently use the facility. For details please contact us.

Where is the Chemistry MSF located?

CMSF is located in room 41 Chemistry.

Sample submission guidelines

Sample preparation plays a critical role in obtaining good-quality MS data. Quality of spectrum decreases as impurities, contaminants or matrices in your sample increase. Presence of salts and detergents, improper solvent choice, and not knowing the right concentration are some examples of factors that adversely affect results. Your MS spectrum is largely dependent on how your sample is prepared. We have summarized some of the things that you should consider before you submit your sample for MS analysis.

In what form should I submit my sample?

Samples can be submitted in solid, liquid, and/or in solution form.

How much sample do I need to submit?

The amount of sample needed depends on the mass spectrometry technique used. In general, 1 mg/ml of sample in solution (not exceeding 200 μl) or 1 mg in solid form is enough for all applications. If you have a limited quantity of sample, please contact us. Please note that, due to the current situation, samples cannot be returned unless requested.

What solvent can I use?

Solvents such as water, methanol, acetonitrile, chloroform, tetrahydrofuran, and dichloromethane are generally accepted for MS analysis. If you are submitting a sample in solution, please indicate on the submission form the solvent that your sample is dissolved in and the solvent in which your sample is soluble.

Generally viscous solvents like dimethylsulfoxide (DMSO) and dimethylformamide (DMF) are not accepted as solvents for mass spec analysis. However, if your sample is only soluble in these solvents please contact us.

Samples can also be submitted in buffers for ESI or MALDI analysis if they are in one of the following MS compatible buffers: ammonium acetate, ammonium formate, ammonium hydrogencarbonate at concentration 10 mM or less. Acid additives such as acetic, formic, and trifluoracetic (TFA) acids are acceptable.

Avoid using salts, phosphate, HEPES, citrate or sulfate buffers, detergents (Tween, Triton, NP-40, SDS), urea, glycerol, carbohydrates, EDTA, GnHCl, plastics and plasticizers, polyethylene glycols (PEG) and other polymers that interfere with the ionization of your analyte.

If you have salts or detergents in your sample, please contact the CMSF staff. Some samples can be cleaned up using a ZipTip (C4 or C18) to remove salts and buffers. There is an additional charge for ZipTipping. Note that not all samples can be cleaned with ZipTip.

What are the specifics for each ionization technique?

GC-MS
Sample concentration

1 mg of sample is enough for pure solid, liquid, or oil samples. Solutions can be submitted not exceeding 1 mg/mL in a suitable solvent for GC-MS.

Solvent

GC-MS requires volatile organic solvents such as dicholormethane, hexane, methanol, ethyl ether etc. GC-MS can't be performed directly on samples dissolved in water.

Avoid

Some classes of compounds are not amenable for GC-MS and should not be submitted for GC-MS analysis. Avoid using a strong acid or base, salt, water, plastic vials and parafilm.

ESI Direct Infusion
Sample concentration and amount

For direct infusion ESI, at least 0.1 mg of sample may be needed for pure solid, liquid, or oil samples. Solutions should be 50 to 100 μM in a suitable solvent for ESI. We need at least 100 microliters of solution at a concentration of 50 to 100 μM in a suitable ESI solvent to run the sample.

Solvent

Suitable solvents for ESI include methanol, acetonitrile, and mixtures of water and acteonirtile or methanol. Samples are accepted in pure water, tetrahydrofuran and dichloromethane, but cannot be run directly from these solvents.

MALDI
Sample concentration and amount

For MALDI, amount of sample will depend on mass. For masses between 500 and 2000, 0.1 mg may be sufficient for pure solid, liquid, or oil samples. For higher masses, higher amounts of sample may be needed, depending on the mass, purity, and type of sample. Solutions should be at least 100 μM concentration, and we need at least 5 μL of solution in most cases.

Solvent

Suitable solvents include water, methanol, dichloromethane, acetonitrile, and others.

What do I do with samples that need special storage or treatment?

Light-sensitive

Samples that are sensitive to light can be placed in a vial covered with aluminum foil.

Low temperature storage

If a sample needs to be kept at low temperatures (refrigeration or freezing), please find a mass spec personnel or, place it in one of the trays on the refrigerator or freezer and write down your sample ID on the sample vial and write down the location of your sample tray number (1, 2, or 3) and row (A, B, C, etc.) on the sample submission form.

Air sensitive

Samples that are air sensitive or unstable samples need special attention. Please contact us in advance to make arrangements before submitting the sample.

Acid/base sensitive

Some samples can degrade if an acid or base is added to the sample. If you are submitting a sample that is sensitive to acid or base, please indicate so.

Aprotic solvents

Generally all ESI samples are diluted and run in methanol. If your sample is sensitive to aprotic solvents, please indicate so.

Do I need to provide a chemical structure?

Please provide us with a chemical structure and formula of your analyte. The structure helps us to determine the ionization method and interpret data.

What is unit mass or accurate mass? Which one should I request?

Unit mass

In unit or nominal mass, the mass is generally accurate to within a few tenths of a Da. Mass spectrometers that are labeled as low resolution normally provide unit mass.

Accurate mass

In accurate mass measurement, mass is accurately determined to four decimal places using a high-resolution mass spectrometer. Typically, mass accuracy below 5 ppm is provided. Accurate mass is only provided for samples submitted for ESI and APCI.

Data

When should I expect MS data?

Typically we provide data within 24 hours of sample submission. ESI samples are run frequently throughout the day and results may be available within the same day. Unless otherwise noticed, we run MALDI samples every day at 3:30 PM. and results may be available after 5:00 PM of the same day.

Where can I pick up my analysis result?

You can pick up your analysis result from room 41 Chemistry. We normally print results and attach to the sample submission form, unless an electronic copy is requested.

Can I get an electronic copy?

We provide a text file of the MS data for all researchers upon request. We can only provide a PowerPoint presentation of the MS analysis results for researchers who are located outside the Chemistry building if requested. We don't provide a PowerPoint presentation for researchers located in the Chemistry building.

How long can my data be stored with the MSF lab?

Data will be stored within MSF for only two years. It is your responsibility to obtain a copy of your data within the time frame.

Publication

What are the rules or policy for publication or presentation of data obtained from MSF?

Research carried out in part or in full using MSF services with services and/or contributions requires acknowledgements of facility, facility and staff, or co-authorship and acknowledgment of facility. Details are given in the acknowledgment policy.

What should we include in our experimental or results section?

If you are writing a manuscript and you are going to include data obtained from MSF, please contact us and we will provide experimental details.

Should we send our publication once it is accepted?

If you publish a paper that includes data obtained by MSF, it is mandatory that you send us citation of the publication or a PDF file once your work is published on the web.