Chromatography Forum

Does anyone have practical experience with filtering solvent extracts (in methanol or dichloromethane etc) through filters designed to remove viruses - which have 20 nm pores ? The smallest pore size that I have ever used was 0.22 micron. Since I am working at trace levels in horribly complex mixtures contamination with plasticizers etc, and absorptive or adsorptive losses are a concern. Ideally a syringe tip format would fit the bill.

Thanks in advance.

Peter

Check ultra-filters from amicon (Millipore-Merck?), Whatman, etc.

Check ultra-filters from amicon (Millipore-Merck?), Whatman, etc.

Thanks, Hans

These nearly all seem to be aimed at large molecules in aqueous systems - have you ever used them with organic solvents ?

Peter

Also not been under 0,22µm, but we have used some filters from like whatman for organic solvent such as methanol etc for sample prep before UV-VIS analysis or mix aqua/organic for LC analysis or even some nylon filters after dervitsings to GC analysis.

Sadly it is not allways easy without contacting suppliers to find exatly which solvents has been tested with filter of intrest.

Thanks Krickos, Anopore syringe tip filters (and possibly others that I have not found yet) come with 0.02 um pores so I'll drop an e-mail to Whatman.

Peter

I have used H2O/org. mixtures on amicon membrane filters, probably never pure organic solvents. Whatman has inorganic filters which should have no problem with organic solvents used in HPLC.

Does anyone have practical experience with filtering solvent extracts (in methanol or dichloromethane etc) through filters designed to remove viruses - which have 20 nm pores ? The smallest pore size that I have ever used was 0.22 micron. Since I am working at trace levels in horribly complex mixtures contamination with plasticizers etc, and absorptive or adsorptive losses are a concern. Ideally a syringe tip format would fit the bill.

Thanks in advance.

Peter

I've used these for small molecues:

6809-2102 Anotop 25 Syringe Filter, sterile 0.02 µm, 50/pk

http://www.whatman.com/AnotopSyringeFilters.aspx

In my case I was doing a dissolution assay for a nanoparticle drug delivery system to remove the particles and measure what was in solution.

- Karen

Thanks Karen

What were your samples dissolved in ?

I have e-mailed Whatman - still waiting for a reply.

Peter

Thanks Karen

What were your samples dissolved in ?

Aqueous media with a surfactant. The membrane is alumina based so it should be fine with most organic solvents.

- karen

Thanks Karen

Extractables from the housing are also a potential problem with organic solvents.

Peter