My God,

I have been doing research on protein adsorption since the 70th.

If you find a sustainable solution to this problem, please Contact me. We will solve the problem of marine biofouling, Biomaterial infections and all problematics related to biofilm formation ! A multi billion USD industry

You asked for advice. Adams suggestion of using non-ionic detergent like Brij, Triton and Tweens is the most straight forward (and inexpensive) way. The non ionic detergents are mild to proteins (Eg antibodies) and does not destroy them. They are very effecting preventing protein adhesion to most kind of hydrophobic polymers, but they are ineffective to prevent protein adsorption to hydrophilic Surfaces as glass. Some of the long chains detergents like the Brij serie also adsorbe to hydrophobic plolymers and by making a precoating with Brij detergent you got a protein repellent Surfaces (to some extent) without addition of detergents in the proteins. All of those non-ionic detergents containing PEG as the principal protein repellent agents.

The glass Surface is a problem, as most metal oxide Surfaces. Sodium dodecyl sulphate (SDS) is very effective on glass due to electrostatic repusion, but SDS binds very firmly to proteins and destroy most of them. Modifications of glass with PEG is a possibility but it is not very easy (or inexpensive) to make such a modification on glass.   Be also aware of that proteins undergo conformational change (denaturation)  adsorption to most solid Surfaces. this is a Time dependent phenomen wich mean that the protein will be increasingly more difficult to wash away from the Surface with time.  (minutes to weeks). I will visit Rio de Janeiro in July. Maybe we can meet over a beer or something to have a chat about this.

There are several concepts to reduce unspecific protein adsorption.

Most prominent is the modification by polyethyleneglycol (PEG) related compounds chemically attached to the material of choice.

But also polyelectrolyte multilayers (PEM) adsorbed by the layer-by-layer technique can prevent the adsorption of proteins, which are due to their isoelectrical point like charged to the outermost (last) adsorbed polyelectrolyte layer. E.g. cationic lysozyme (IEP~11)   is repelled by an outermost polycation layer or anionic human serum albumin is repelled by an outermost polyanion layer. If you are interested you my want to look into these papers:

Biomacromolecules 2006, 7, 1285-1294

Macromol. Rapid Commun., 22 (6), 390-395 (2001)

Macromol. Rapid Commun. 20, 607–611 (1999)

or patents by Cibavision (Winterton, Vogt, Lally, Stockinger etc.), in which contact lenses are modified by PEM to prevent protein adsorption (from tear fluid).

Best regards,

Martin Müller

Dear Martin, thank you for your valuable comments.

Best regards,

Gustavo

If it is compatible with your procedures, addition of a low concentration (e.g. 0.005%) of a non-ionic detergent such as Brij-35, Tween-20, or Triton X-100 to the solution will help prevent protein adsorption to hydrophobic plastic surfaces. Glass could be treated with a solution of polyethylene glycol (PEG) and dried, but I wouldn't recommend using glass. Polysulfone ultrafiltration filters are low protein binding. Plastic containers should be made of polypropylene.

Dear Adam, thank you for the tips!

Another way to overcome this problem is to add a small amount of BSA to the reaction mixtures (like 0.1% or a little bit more if okay with your experiments). (Even if you run a protein gel, BSA band is clearly identifiable around 60 KDa so, it's easy to differentiate that from the rest of the bands) This might also help you to minimize the adsorption/loosing of the desired protein.

However, it might not be as effective as adding a chemical such as triton-x etc. But, in case if you can't use such chemicals, BSA can be a friendlier option :)

My God,

I have been doing research on protein adsorption since the 70th.

If you find a sustainable solution to this problem, please Contact me. We will solve the problem of marine biofouling, Biomaterial infections and all problematics related to biofilm formation ! A multi billion USD industry

You asked for advice. Adams suggestion of using non-ionic detergent like Brij, Triton and Tweens is the most straight forward (and inexpensive) way. The non ionic detergents are mild to proteins (Eg antibodies) and does not destroy them. They are very effecting preventing protein adhesion to most kind of hydrophobic polymers, but they are ineffective to prevent protein adsorption to hydrophilic Surfaces as glass. Some of the long chains detergents like the Brij serie also adsorbe to hydrophobic plolymers and by making a precoating with Brij detergent you got a protein repellent Surfaces (to some extent) without addition of detergents in the proteins. All of those non-ionic detergents containing PEG as the principal protein repellent agents.

The glass Surface is a problem, as most metal oxide Surfaces. Sodium dodecyl sulphate (SDS) is very effective on glass due to electrostatic repusion, but SDS binds very firmly to proteins and destroy most of them. Modifications of glass with PEG is a possibility but it is not very easy (or inexpensive) to make such a modification on glass.   Be also aware of that proteins undergo conformational change (denaturation)  adsorption to most solid Surfaces. this is a Time dependent phenomen wich mean that the protein will be increasingly more difficult to wash away from the Surface with time.  (minutes to weeks). I will visit Rio de Janeiro in July. Maybe we can meet over a beer or something to have a chat about this.