ScreenTape® P200

Can I run non-reducing analyses of proteins?

Yes, ScreenTape is provided with a range of buffers allowing for both reducing and non-reducing analysis.

How does the Protein stain work?

The stain is a novel amine reactive fluorescent stain.

What is the sensitivity of the Protein platform?

ScreenTape can detect less than 1 nanogram per band.

What is the linear dynamic range of ScreenTape P200?

2ng to 200ng per band.

Do I have to use the P200 loading buffer?

Yes, the system is supplied with all the reagents required for standard protein analysis, and these should not be replaced.

What is the resolution of the P200 platform?

The resolution is similar to a good slab gel. Two bands differing by 15% in size should be easily distinguished. For example, two bands of 39 and 36kDa can be separated by P200, and two bands of 113 and 101kDa are also resolved.

What is the sizing accuracy of the protein platform?

ScreenTape displays an accuracy of ±10%.

How much does the instrument load onto P200?

0.5µl.

Which range of proteins can I run on P200?

Proteins between 10 and 200kDa.

Do I need any additional specialist laboratory equipment to increase the efficiency of ScreenTape P200 sample preparation?

There is no essential additional equipment required. Certain pieces of equipment will however make sample preparation easier and faster.

• An accurate heating block or thermocycler, that can accommodate 0.2ml tubes, would be recommended for sample preparation as an alternative to a traditional water bath.

• A mini centrifuge used to spin down samples before transfer to the TapeStation, will ensure that all liquid is collected at the base of the tubes without any bubbles and will ensure efficient sample loading.

• A 16 channel pipettor to fit the MBP Robotix tips used within the instrument would also be beneficial to the process.

What is the average sample preparation time for 16 protein samples?

12 minutes

What are the storage conditions for the P200 ScreenTape and RNA loading buffer?

ScreenTape P200 should be stored at 4°C. All the reagents for sample preparation should be stored at -20°C.

Can I batch-prepare my samples prior to running multiple ScreenTape?

Yes – batch-prepare your samples according the Lab901 sample preparation protocol. Load and run the first set of samples on ScreenTape and keep the remaining samples on ice, with tube lids on, until ready to run the next ScreenTape. Do not keep samples for longer than 4 hours prior to analysis on ScreenTape.

What is the shelf life of P200 ScreenTape?

Current shelf life product is 4 months at 4°C but new protocols are currently under development which will extend this shelf life further.

Can I use more that 2µl of sample in my stain reaction?

No. The staining reaction has been optimised for this volume of sample, which should be between 0.1 to 1.0mg/ml.

Can I use the loading buffer I use in my slab gel analysis?

No, this is not compatible with ScreenTape analysis of stained protein samples.

My sample is not bright pink following staining, what’s wrong?

Depending on the concentration of sample used following staining, samples will vary in colour. For a sample which is nearer 0.1mg/ml the colour change will be very subtle, and still look blue. A sample used which is 1.0mg/ml will give a pink colour. You should still proceed to analyse samples which do not have a vivid colour change.

My Molecular Weight Standard is very poorly stained and looks weak?

Ensure you have heated the sample correctly for staining. We recommend a calibrated hot block to ensure the optimal temperature of 75°C is used for sample labelling.

Do I need to use the “Run further” option following sample electrophoresis?

No. This is not required for protein analysis. The TapeStation separates samples using a program which is optimally designed for P200 ScreenTape.

Why should I use diluent, is water fine instead?

The diluent has been designed to assist in titrating the sample to the correct pH for staining. It also contains reagents which should reduce sample degradation and improve analysis.

I left my reagents out overnight on the bench, will they be OK to use?

The quality of sample analysis may be compromised. We recommend that reagents are kept on ice during use, and stored correctly at -20°C. The efficiency of the loading buffer in particular may be compromised, and the Protein Stain Solution is sensitive to light and may therefore decrease in efficiency.

Can I run without In-lane Markers?

We advise against this. Molecular weight sizing will not be as accurate.

Can I reduce the time for sample staining from 7 minutes?

No. This time has been selected for optimal sample staining using the P200 Protein Stain solution.

My samples look different to those run on a slab gel and stained with Coomassie, why?

The Lab901 protein staining protocol uses a completely different staining mechanism to that of Coomassie. Furthermore, the amount loaded onto a slab gel is considerably more than with a ScreenTape. Highly comparable results can be obtained by following the Lab901 recommendations on sample buffer conditions and compatible reagents, as well as starting protein concentration.

Can I combine the sample preparation steps into a single heating step?

No, this will not work.

Can I compare the results from samples run on different tapes?

Yes, the GeneTools software allows this kind of analysis. Please refer to the manual for more information.