I'm not familiar with particular formaldehyde removal method in vaccine production but an efficient way for removing CH2O is by using polymers containing NH2 groups. These polymers can remove CH2O in gas form [1]and also if it is dissolved in water [2] (in form of methylene glycol). how it works is as follows: CH2O reacts with NH2 through nucleophilic addition reaction and hemiaminal will form and if you remove water from hemiaminal it will turn into imine which is colorful (due to its double bond). The interesting thing here is that if you add acid to hemiaminal and/or imine the formaldehyde will be desorbed from the NH2 group (since the reaction is reversible) and you can have the formaldehyde and can be useful if you want to detect the amount of formaldehyde that is sorbed by the NH2 polymer. you can check out the below pubs for further info.

Thanks

[1]http://pubs.acs.org/doi/abs/10.1021/ja910366p

[2]http://www.sciencedirect.com/science/article/pii/S0021967300004064

In case a vaccine, to remove residual formalin is necessary to add sodium bisulfite to a final concentration of 0.2-0.25% (must be equivalent to the proposed content of formaldehyde in the product)

By reacting CH2O with Sodium sulfite, NaOH will be a byproduct, again I'm not familiar with vaccine production just wanted to clarify that you will produce base when you use sodium sulfite with formaldehyde.

This method of getting rid of formaldehyde, we used in the preparation of an inactivated vaccine against avian influenza N5N1 for veterinary medicine. By itself, the sodium bisulfite is harmless to organism. A formation of such a secondary product as a NaOH may affect only the pH and then only slightly. This method of neutralization of formaldehyde in the vaccine is widely known, so feel free to use it.

Ultracentrifugation method or addition of Sodium bi sulphite (0.25 %) are well known for removal of formalin from the final product in vaccine production

You can try to use dialisis membarne vs water or sline solutions. "perfusion" should be work 

I have used para-formaldehyde many times for vaccine inactivation in repeated efficacy trials and have removed it from the final preparation by dialysis.  Make sure you get the proper size (MWCO) dialysis tubing (so as to not loose any of your sample/vaccine) and perform multiple buffer changes to remove all remaining formaldehyde.  You can place your sample in the tubing, close off at both ends (they have clips for this), and suspend the tubing with a string (or tubing) in the buffer so all of the dialysis tubing is submerged.  Place the bucket with your suspended sample at 4C (or room temp depending on the sample) on a stir plate with the magnetic stir bar and stir gently enough to provide continual flow of buffer against the dialysis tubing. Replace buffer with fresh buffer until formaldehyde is removed.  You can test the final sample against most relevant cell lines to determine if there is any effect on cell viability.  If your vaccine has a color or tinge to it, you will see the color gradually disappear as it is dialyzed.  Your vaccine may take on extra volume, so you can concentrate it back to its original volume if need be (PEG, spin-concentrators, or ultra-concentrators at 4C).  It may take hours to remove all of the formaldehyde (depending on your final sample volume), so you can perform your buffer changes before you leave for overnight, then in the morning, and at lunch.

Also you can use cellophane membrane tubing, these is no scientific prduct, you can find it in many supermarker, these membrane is used in sausages foods, just remove glycerin with alcohol or cetone per 5 minutes and thats it. After that you can dialisis you material vaccine .. good look!!!

Dialysis or diafiltration is not a efficient way of removing formalin in case of whole cell vaccine like Cholera. where our study proof that it might stuck in cell. Can any one confirm me about bio safety of using sodium bi sulphite?

Dear Mr Kaissar Tabynov.

In regard to your comment: "This method of getting rid of formaldehyde, we used in the preparation of an inactivated vaccine against avian influenza N5N1 for veterinary medicine. By itself, the sodium bisulfite is harmless to organism. A formation of such a secondary product as a NaOH may affect only the pH and then only slightly. This method of neutralization of formaldehyde in the vaccine is widely known, so feel free to use it."

After adding formaldehid to the bulk, when should we add the sodium bisulfite? how long and in what temperature should we incubate the bulk?

Thank you for your kind response

I can answer a part of it. Formaldehyde is a very reactive compound and it can readily react with sodium bisulfite at room temperature. There are ways that you can actually measure how much formaldehyde you have in your solution. You can refer to Formaldehyde book by Walker for more details.

Remember to test your final product on relevant cell lines or PBMC to see if it effects viability.