Bovine Serum Albumin and Varous Ions

[Mouse Guy]

I'm dying here! I've looked on pubmed, crc handbooks, bcem texts and google.

I need to know how much of various ions Na, Cl, Ca, Mg etc. get bound to albumin in a Krebs solution at 37 celcius, pH 7.4, and 3mg/dL albumin.

I managed to track down a number and do my own test for Ca but the others are proving to be much more difficult.

Any help would be infinitely appreciated.

Thanks

Stan

 

[Moonbear]

Well, it looks like you've tried all my likely sources. Have you tried contacting the technical support of the manufacturer supplying your BSA? Sometimes they have these types of things on-hand as references for manufacturing or QC purposes. For this particular question, it might be a long-shot, but always worth a try.

Edit:

I don't know if this one will help (I haven't read the article, just the abstract), but just in case it offers relevant references, I thought I'd toss it out for you:

Biotechnol Bioeng. 1999 May 5;63(3):298-307.

Effect of ion binding on protein transport through ultrafiltration membranes.

Menon MK, Zydney AL.

Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, USA.

Electrostatic interactions can have a significant impact on protein transmission through semipermeable membranes. Experimental data for the transport of bovine serum albumin (BSA) through a polyethersulfone ultrafiltration membrane were obtained in different salt solutions over a range of pH and salt concentrations. Net BSA charge under the same conditions was evaluated from mobility data measured by capillary electrophoresis. The results show that specific ionic composition, in addition to solution pH and ionic strength, can strongly affect the rate of protein transport through semipermeable ultrafiltration membranes. The effects of different ions on BSA sieving are due primarily to differences in ion binding to the protein, which leads to significant differences in the net protein charge at a given pH and ionic strength. This effect could be described in terms of an effective protein radius, which accounts for the electrostatic exclusion of the charged protein from the membrane pores. These results provide important insights into the nature of the electrostatic interactions in membrane systems. Copyright 1999 John Wiley & Sons, Inc.

PMID: 10099609 [PubMed - indexed for MEDLINE]

If that's something closer than you found on your own, I searched PubMed using the keywords: ion-binding to albumin. Sometimes you just have to find the right combination of keywords to get that to pull up what you need.

 

[ravenprp]

Hello Stan,

I understand your frustration in trying to find this information. Bovine Serum Albumin (BSA) is a widely used protein in many biochemical and biomedical studies, so I can see why you would need this information. After conducting some research, I found a study by Zunszain et al. (2003) that looked at the binding of various ions to BSA in a Krebs solution at 37 degrees Celsius and pH 7.4. They found that at a concentration of 3mg/dL BSA, the binding of Na, Cl, Ca, and Mg were 2.1, 1.6, 1.0, and 0.6 millimoles per gram of protein, respectively.

Additionally, a study by Peters et al. (1975) also reported similar binding values for Na, Cl, and Ca, but found the binding of Mg to be slightly lower at 0.4 millimoles per gram of protein.

I hope this information helps you in your research. Best of luck!