There are a number of possible causes for the noise in the spectrum. From the slice of the spectrum you uploaded it seems that the noise is located in a specific region: have you recorded a 1D of the sample? you could check if in the 1D, there are some sharp peaks corresponding to noise. Another thing you can change is the mixing time: the protein is small, you could use 120-150ms mix time. Double check also number of scans, it should be 8 or multiple of 8. A final comment that arise from what you wrote: you should always check who set up the PROSOL and double check the p1 cause often prosol are not updated and pulsecal not always work well.

Hope this help

Regards

Dear Chandrakala,

I see in your protocol, that you did not perform a adjustment of the receiver gain (rga command) which is crucial if you have huge e.g. buffer related signals. Otherwise I fully agree with Domenico and Clemens. ALWAYS run a 1D 1H!

What I normally do is to run the rga command which returns a receiver gain RG which I then multiply with 0.8. Sometimes I made bad experiences if I used the rga value.

Hope this helps

Alfred

I agree with previous answers.

According to your picture, I see that you have also a problem of phasing mainly in F2 dimension (green color at the left, red at the right) on the most intense peaks and also.

From my experience, to reduce the noise, I recommend :

-to calculate the noise in F1, from a selected band without signal in the diagonal, and remove it on the other regions (with Bruker software, type 'proj' and select a 'calculate positive projection' with raw numbers for the selection of the band; Then type 'sub2').

-In addition, I recommend (if not done) to add linear prediction points in F1 (in 'procpars' it is LPFc: linear prediction forward complex; you need to optimize the number of coefficients and the number of points to predict).

-try different functions of apodization, with a correct tuning of the parameters, in both dimensions.

Hope it helps,

Gildas

@Gildas Bertho @Alfred Ross @Clemens Anklin @Domenico Sanfelice Thank you all for the input. I shall check all the above mentioned possibilities to improve the spectrum. I appreciate the time taken by you to answer my querie....