I am preparing some lipids in solution CHCl3/CH3OH but i can't use gilson pipette to avoid the plastic and I use only Hamilton Syringe. Do you know if there are some special tips for CHCl3?
Hi Anna,
if you work with small volumes up to 1 ml then as you wrote, Hamilton syringes is the best choice, if you want to use larger volumes, there is also some syringes made out of glass or use small glass beakers. and you should make sure that your glass wares you work with is cleaned by organic solvants otherwise you have a contamination in your lipids.
i hope i got you write,
wasim
You could use a positive displacement pipette from Gilson (MICROMAN) adapted for organic solvent (including CHCl3) ; specific tips are avalilable for such pipettes. Be cautious to use high quality tips (Gilson)
see at http://www.analiticaweb.com.br/informe/microman2012/catalogo_microman.pdf
I use Glass Pasteur Pipettes. I think you can try it. it might be helpful
Drummond sells some microdispensers with glass capillary tips that I use for work with CHCl3. They work well and you can dial the volume that you need.
Use glass pipets. There is no plastic suitable for organic solvents.
Polypropylene is resistant to CHCl3 and I believe most tips are made of polypropylene. Glass capillary tips work well also.
Depending on the volume, Hamilton syringes, glass graduated pipettes, and for volumes above 10ml (eg. making solvent mixes for HPLC) we use glass cylinders pre-rinsed with methanol and chloroform sequentially to avoid contamination. Also, if you're working with PIP2 or PIP3 you might want to consider silanating glassware such as small glass tubes and pasteurs to prevent the lipids sticking to the glass.
You could use glass pipettes, there are available for different volumes.
in my own experience all tips made in polypropilene are resistant to chloroform. I analyze lipids with MALDI MS and I have never seen contaminations or differences in the profiles when I use polypropilene tips. the only problem is when using colored tips, in that case you will see a clear signal due to colored compound. someone here suggested positive displacement pipettes, that's the best choice in my opinion too
I agree with Roberto, most clear tips are fine for short term exposure to chloroform mixtures. We generally prewet the tip to ensure more accurate measurements. However, you should use only glass to mix the solvents and for storage purposes. Make sure you always use the same manufacturer for the chloroform and the same product number. Different product numbers are stabilized with different products, so stick to the same product for consistency. Never store samples with chloroform in anything but glass, long term storage can bring chemicals out of the plastics.
I agree with all aforementioned. However I would like to show my personal experience. In our lab we use Folch extraction and other variations in the isolation of lipids from foodstuffs to biological samples. The main analysis is HPLC-ELSD and here comes the problem: during isolation we cannot use nothing but glass if not we get ghost peaks. Falcons and vials have to be always made on glass. On the other hand, for short time exposure (pippetting) plastic seems not to have any effect. Even more, we have found (as other have previously published) that dichloromethane is avery good alternative to chloroform.
However I am currently finding many papers changing chlorofom/dichloromethane by MTBE with very good results. Please check attachment.
Article Lipid Extraction by Methyl-Tert-Butyl Ether for High-Through...
1. Any plastic (including polypropylene) contains plasticizers, normally phthalates. Anyone who works with GC-MS has this experience. They appear as ghost peaks possessing the intense ions at m/z 149. Thus, only glass should be used with organic solvents.
2. There is one specific issue with chloroform. It slowly degrades to phosgene and HCl, which are harmful for many lipids.
I never used anything different from metal and glass for lipid solutions. CHCl3 must be stabilized with 0,5% ethanol (see the label). Distilled, anhydrous CHCl3 is unstable and is oxidized to COCl2 in a week or so.
In our practice, pipetting and short-term storage of lipid solutions in chloroform at -20 C in PP "eppendorf" tubes is fine. As for stabilizers, for TLC and extraction we always use the freshly distilled CHCl3 due to batch-to-batch variations in EtOH stabilizer amounts.
There are special tips which can fit to ordinary pipettes. I attached links for couple of them below. They are carbon fiber tips and safe to use it with organic solvents. I would avoid using ordinary tips for at least important experiments. I heard a case where a contamination from the tips lead to lipid membrane fusion. I used positive displacement pipettes, they are great but if you pipette different kind of solutions many times, using a positive displacement pipette and changing its tips will be time consuming. These carbon fiber tips are handy and most of the cases more affordable than glass tips for the positive displacement pipettes.
http://www.sigmaaldrich.com/catalog/product/sigma/s8064?lang=en®ion=US
https://www.fishersci.com/shop/products/thermo-scientific-art-solvent-safe-carbon-filtered-pipette-tips-2/p-162082
We used glass pipettes for our work on lipid extraction using chloroform.
- Badges
- Science topic
- Similar topics
- Biological Science
- Molecular Cell Biology
- Culture Cells
- Cell Line