Glass syringes when filtering samples?

Discussions about sample preparation: extraction, cleanup, derivatization, etc.

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Hi, we've always used glass syringes when needing to use syringe filters and I wondered if people viewed this as old school? Our samples are frequently in HPLC grade MeOH or ACN, hence the original decision to use glass rather than plastic. Our stock of sryinges is becoming tired with plungers freezing frequently and before I buy the lab news ones, figured the practice should be reviewed. We're in a research environment (university) so always working with different methods and samples. Any help is greatly appreciated! Thanks :)

Edit: I should have specified that all our samples are analysed by HPLC (UV detection)
For us it depends on solvent used and what we are analyzing for. If I am looking for Carbamate Pesticides or glyphosate in drinking water sample I will filter those using a simple disposable plastic syringe, since the water doesn't damage the black rubber plunger tip. If the solvent is more aggressive I prefer glass syringes with teflon plunger tips since those are more inert. If you use ethyl acetate or dichloromethane you will definitely have to use the glass/teflon because those solvent will dissolve the black rubber plunger tip of the disposables on contact.

If you are filtering water samples with nylon syringe filters you can easily get away with the cheapest BD disposable slip tip luer syringes, as the filters normally will not fall off even when using moderate pressure. If you are using teflon filters you may need luer lock tips because the pressure needed may be enough to cause the filters to pop off the tips.
The past is there to guide us into the future, not to dwell in.
James_Ball wrote:
... If you use ethyl acetate or dichloromethane you will definitely have to use the glass/teflon because those solvent will dissolve the black rubber plunger tip of the disposables on contact.
...

If the rubber plunger tip is the only concern then you may use 2-part disposable syringes: eg. http://polfa.pl/strzykawki-dwuczesciowe ... l/?lang=en
If filtering is the last step before injection, we prefer to use a compress filter vial for the solvents you mention. It saves a step/consumable.

If filtering is needed before injection for common GC solvents (dichloromethane, hexane,..), we typically combine filtering and drying; using a pipette tip filled a little bit of cotton wool with sodium sulfate on top of our GC vial.

Alternatively, centrifugation is also an option!
We used glass syringes and little stainless steel filter holders with replaceable membranes to filter samples - in the late 1970s. Yes, each had to be carefully cleaned before the next membrane and sample were used, pain in the butt!!!

Later on, we didn't really like the idea of the black rubber plunger on BD plastic syringes, so we obtained 5ml disposable plastic syringes made in Europe that did not have such rubber/plastic seal and used those with disposable filter units.

Later, we moved to Whatman Autovials, an all in one system.

Note that none of these is especially cheap. And of course disposable syringes with plastic/rubber seals could be checked out and validated not to interfere with said assays.
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