Protein Measuring: Standard vs Sample Solutions

[mountain]

When I make the standard curve then each standard solution is prepared like this:
800ul water
20ul each standard solution
200ul dye concentrate


The samples are prepared like this:
800ul water
4ul each sample solution
200ul dye concentrate

I wonder if I for instance get 0.5mg/ml on one of my sample. Does this mean that this value is the concentration of the original sample or should I multiply with 5 since the volume of the standard is larger (20ul) then the volume of the sample (4ul)?

 

[detta]

Could you be more specific of how you are measuring your proteins?
Are you using a spec?
Usually the standards just standardize your samples, a ladder to measure against.
The only thing you should be compensating for is the volume you put in. You are measuring the concentration /4ul. This then should be calculated so you have a value either per ul or per ml. Its hard for me to say exactly because I'm not sure how you are measuring the protein concentration. Usually the standards tell you the amount of protein you are adding and everything should be calculated to be on the same scale (eg how many ug/ml and not ug/5ml for one and ug/3ml for another sample).

 

[ravenprp]

The concentration of the original sample should not be affected by the difference in volume between the standard and sample solutions. This is because the concentration of the standard solution is already known and used to create a standard curve, which is then used to calculate the concentration of the sample. Therefore, the concentration of the sample should be accurate regardless of the volume difference. However, it is always a good practice to double-check your calculations and make sure they are accurate.