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- Protein Sample Preparation
- Protein Gel Separation and Recovery
- Mass Spec Standards

Protein Sample Preparation (click a post below to read)
Tips for overcoming problems with MALDI protein identification
           So, you have gone through days of grueling lab work and tomes of protocols to prepare a sample for the all telling MALDI analysis. When the...
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author: matthew.maust | date created: Jun 01, 2012 | comments: 0
Quantifying protein in samples containing SDS
Question from the forums:
Hi everybody,
I...
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author: matthew.maust | date created: May 23, 2011 | comments: 0
Unique uses for albumin and IgG depletion
Many researchers today are interested in the proteomes of tissue samples from many sources. One problem that is faced when analyzing samples derived from various types of sera is the presence of album...
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author: matthew.maust | date created: May 06, 2011 | comments: 0
Are there any special considerations when using the cell lysis kits?

 It is important to pay careful attention not to damage the cells before the actual cell lysis step.  Severe sample loss can occur by damaging the cells prior to lysis.  During th...
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author: haddon.goodman | date created: Mar 17, 2011 | comments: 0

Are urea and glycerol compatible with your Titanium Dioxide tips?

The presence of urea, ampholytes and glycerol is problematic for TiO2 selective enrichment. There has to be some form of sample clean-up before en...
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author: haddon.goodman | date created: Mar 17, 2011 | comments: 0

I’ve heard that when using functionalized pipette tips for cleanup or enrichment that pipetting speed can directly affect the results. Is this true?

For our Titanium Dioxide ProteaTips (SP-124 and SP-125), it is best to go up and down very slow while pipetting.  The slower the better, because the phosphopeptides have a weak interaction ...
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author: haddon.goodman | date created: Mar 17, 2011 | comments: 0

Does centrifugation of samples for longer times or higher centrifuge speeds add any benefit using your Protea SpinTip products?

All of our SpinTip products (SP-150, SP-151, SP-152, SP-155, and SP-154) have the fritted tips.  The SpinTip protocols recommend centrifugation at 4,000 rpm for 3 minutes. The frits are tes...
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author: haddon.goodman | date created: Mar 17, 2011 | comments: 0

Are there any reagents that will inhibit the performance of your enzymes?

When using Glu-C, acetonitrile cannot be used during digestion. The presence of the organic solvent will denature the enzyme and yield poor digestion.  Our digestion buffer contains 1% acet...
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author: haddon.goodman | date created: Mar 17, 2011 | comments: 0

Monolith Products - Product selection

Q: Which Polymeric Monolith Chemistry is appropriate for my sample? Should I use the single use tips, the chromatographic columns, or the plates for my sample(s)?

A: Single tips are u...
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author: haddon.goodman | date created: Mar 01, 2011 | comments: 0

After serum samples are depleted of albumin or IgG using your depletion sample prep kits, are the samples ready for further downstream analysis such as SDS-PAGE, 2D gel electrophoresis or mass spectrometry?

It may be necessary to desalt samples using a centrifugal ultrafiltration unit (SP-021 and SP-022) to remove serum salts, buffer salts and small molecular weight species from the sample.


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author: haddon.goodman | date created: Feb 14, 2011 | comments: 0
What is the total amount of serum I can put in a single Albumin or IgG Depletion Sample Prep SpinTube? Diluted amount?

We recommend no more than 10 μL of serum (diluted to 400 μL with our activation buffer) be added to the SpinTube.


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author: haddon.goodman | date created: Feb 14, 2011 | comments: 0
After degrading the surfactant, I get a precipitate forming in my tube? Why?

This is due to the fact that your proteins are no longer being solubilized by the surfactant present. Instead of degrading the surfactant you may need to try an alternative clean-up method, poss...
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author: haddon.goodman | date created: Feb 14, 2011 | comments: 0

What is the heat stability of our Progenta Surfactants, do we know the heat stability of them?

The surfactants are organic molecules, so they can be combusted if the heat is too high (somewhere higher than 200 °C – we have never tested it). Heating the surfactants in an aqueous ...
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author: haddon.goodman | date created: Feb 14, 2011 | comments: 0

Is it normal to get a white solution when the surfactant is dissolved at 0.5% in a solution of TEAB -TriEthylAmmonium Bicarbonate 0.5M?

There is a white precipitate forming which is the surfactant triethylammonium salt. The triethylammonium cation adds six hydrophobic carbons to the surfactant anion which already has twelve hydr...
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author: haddon.goodman | date created: Feb 14, 2011 | comments: 0

What products can be used to help dissolve my samples for in-solution digestion?
You can add our Anionic Acid Labile Surfactants in a concentration of 0.05% - 0.1% to help in resuspension of your sample.
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author: haddon.goodman | date created: Feb 10, 2011 | comments: 0
How do I know which Progenta Surfactant is the appropriate choice for my sample?
We make an assortment of Progenta acid labile surfactants to provide a safe alternative to detergents (e.g. SDS and CHAPS) that are commonly used in proteomics work. Below is a list of our acid labile...
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author: haddon.goodman | date created: Feb 10, 2011 | comments: 0
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