Dear Gube, Methanol is only recovering solvent of polymers, but if you want to purify the the polymers, first you have to dissolve the biopolymers in suitable solvent and then u have to precipitate the polymer. In case of biopolymers, most of them are soluble in aqueous media (water), so that you can dissolve them in water and you can precipitate either in Acetone or methanol
It totally depends on the nature of polymers. They are generally soluble water.So you can try with ether or acetone (cold condition) for precipitation. You can further purified it by slow evaporation technique.
Considering the application, you might face trouble due to traces of methanol in the final material.
I don't think it will be a problem using methanol, but yes the biopolymer should be free of its traces later on. Due to this reason I have used ethanol with a biopolymer (containing cellulose), which evaporated easily without affecting the polymer. You can at least try.
Methanol may not be advisable for bio-medical samples because if the methanol is not well washed out it may metabolized to formic acid or formate salts, which is poisonous to the central nervous system, and may cause blindness, coma, etc...
You can use ethanol for your precipitattion which solvent is less toxic than methanol unless you really have to use it. I guess it's OK to use methanol but make sure you completely remove it from your final product .
It is impossible to completely remove any solvents used for the precipitation of polymers by vacuum drying. However, if your polymer is soluble in water, which I presume it is, you can precipitate with methanol, remove most of the methanol under vacuum, disolve the polymer in water and then freeze dry it.
Methanol is a suitable solvent for biopolymers but you can use a mixture of water, methanol and acetic acid as well. For the purification purpose, you have to precipitate the biopolymers in a solvent.
For biomedical purpose, you can use ethanol as a solvent for biopolymers. Ethanol is the active principle in intoxicating drinks, in which ethanol can be produced by fermentation of sugar using yeast. It can be easily evaporated as well so it can be completely removed.
No. Methanol can be dangerous for health. You can use other solvents, such as, propanone or ethanol. Which polymer are you intending to use?
It is far better to use ethanol because first, you need get it out completely from the polymer you are making. ethanol can be taken out by rinsing it with MilliQ water or directly with distilled water. Second, due high volatility, you can take it out within a vacuum oven even without heating it ( after both rinsing methods. )
The purification of the biopolymers for biomedical applications in supercritical fluids is possible. The supercritical carbon dioxide is the most preferred solvent
Flush the methanol out with ethanol. Then if possible dialyse with MilliQ and lyophilize the polymer. If you dont have the option for lyophilization then a simple vacuum setup should suffice.
A method of purification without methanol as suggested by other replies will be preferred because of toxicity issues, even if there seems to be no residual methanol. A method of purification then depends upon the particular biopolymer. First a solvent is required and after dissolving filtration will remove insoluble impurities, then pour the solution into a cold non-solvent, maybe ethanol instead of methanol, with rapid stirring, to precipitate the biopolymer.
An example is purification of poly(3-hydroxybutyrate) (PHA) and its copolymers. Dissolve in dichloromethane, filter through a microporous filter such a a PTFE type (not filter paper), precipitate into ethanol, dry by atmosphere evaporation then in a vacuum oven. An impurity of protein can be removed by the filtration. The protein is present because PHA is formed by bacteria.
Well explained by Robert. If you use methanol, then you should purify it with other non toxic solvents. DCM can work as well. Or you better try ethanol as well.
Methanol is harmful and not suggested to use it. But selection a suitable solvent for this purpose is dependent of some parameter. These parameters are polymer type, purification process, reaction condition (if you had some modification on polymer), and etc.
There are many different solvent that used in polymer processing especially for biomedical application.
Solvent such as dicholoromethane, acetone, isopropanol, ethanol, dimethyl solfuxide, ethyl acetate, hexane, etc.
For any water soluble polymer, the method of choice to remove traces of organic solvents would be to disolve the polymer after purification in water and freeze-dry the solution. This gives a solid polymer free of water and organic solvents. Dialyis against water woild also remove the traces of organic solvents but one is left with an aqueous solution of the polymer. The use of another solvent, such as 2-propanol or ethanol, during polymer purification by precipitation may not be practical as their solubility parameters are much lower than methanol, which could lead to incomplete precipitation or clumping of the precipitate.
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