Re: [ccp4bb] Concentrating protein

[Guenter Fritz]

A mild and quick method is to use dry Sephadex G-25. The material will 
swell and take up all the liquid except molecules larger than ca. 5 kDa.

Dear All,
we have GCSF protein produced in inclusion bodies. we solubilise it refold 
it and then concentrate it using proflux system. still the concentration 
of the protein we get is less and volume is more for us to load in Ion 
exchange chromatography. is there any simple technique that can be 
performed in lab without using any hi-fi instrument to concentrate the 
protein in small volume of buffer. the protein we obtain is about 0.7 
mg/ml and we get 450 ml solution. our column is 110ml lab scale and we 
have to work in that only. i have heard of NH4SO4 precipitation. but it 
requires protein conc more than 1 mg/ml.

kindly help me to progress in my experiment.