Eloi Camprubí Casas

12 Questions 15 Answers 0 Followers

Questions related from Eloi Camprubí Casas

What's the concentration saturation of H2 gas in water at 50 bar and 70 degrees C?

I'm trying to figure out the saturation concentration of H2 gas into water which has been presurised at 50 bar (and heated at 70 degrees C). I can't seem to find any relevant source of information...

03 March 2019 4,914 2 View

Does anyone know of any dialysis membrane NOT made of organics (e.g. cellulose, etc.)?

I am performing some experiments and I'd need to buy a dialysis membrane (not a filtration membrane) that is not made of organic molecules. Teflon (C-F) would work, but haven't been able to find...

10 October 2018 9,525 2 View

How could I dissolve/remove Fe(Ni)S precipitates?

I am developing a microfluidics chip most probably made of glass or polycarbonate polymers. My experimental plans will involve the precipitation of thin Fe(Ni)S minerals along some of the...

05 May 2018 6,271 4 View

Does the quantification of formaldehyde inevitably involve some sort of chemical derivatisation?

I am planning experiments which should produce formaldehyde and I aim to quantify it. The amount generated will be small (upper nano to micromolar range). Ideally, I'd like to use tests that...

05 May 2018 6,477 13 View

Which SPE cartridge would you recommend to get rid of charged ions?

I'd need to buy some SPE cartridges for a purification step of my samples (which are going to be analysed using GC-MS after derivatisation with TMS). Basically my samples contain sugars...

04 April 2017 5,345 3 View

Are phosphates dissolved in dichloromethane (DCM)?

I derivatise aqueous samples containting sugars for GC-MS analysis by acetylating the hydroxyle groups of the sugars (forming alditol acetates). I've tested this and it works just fine. Recently,...

03 March 2017 5,191 4 View

Is there any substance that can be used to aid in organic phosphate quantification in P-NMR?

In the past I have used internal standards (IS) for quantification of organic molecules in 1H-NMR. Simply by spiking exerimental samples with a few microliters of a internal standard solution (of...

10 October 2016 860 14 View

Why the 1H-NMR signal of N-acetylglycine appears as 3 peaks at low pH, but instead as 2 at high pH?

If I analyse by 1H-NMR (with water suppression) a solution of 200 mM N-acetylglycine in water (in 10% D2O-90% H2O) at pH 2, 3 major peaks appear: a doublet at 3.7 ppm and a singlet at 2 ppm. The...

08 August 2016 8,265 6 View

Is a fully (negatively) charged phosphate group a better or a worse leaving group compared to a protonated (neutral) phosphate group?

I have a reaction between an amine and acetyl phosphate. The results can be that the amine can be phosphorylated or acetylated. NMR experiments suggest that at high pH what happens mostly is...

07 July 2016 2,912 3 View

Can using methanol damage a freeze-drier machine?

I am trying to freeze-dry samples made of 0.1mL water and 0.5mL methanol. My freeze-drier only reaches -55C and methanol freezes at about -98C so the samples are never actually frozen. The vaccum...

07 July 2016 8,928 1 View

Is it possible to use an LCMS column that is too long to physically fit inside the instrument slot?

I bought a new LCMS column that is very long as I require of a very good analyte separation. Just realised the column doesn't physically fit inside the LCMS instrument slot but I would swear I've...

07 July 2016 5,994 3 View

How can I quickly detect the presence of dipeptide gly-gly in solution?

The LC-MS setup I currently dispose of wouldn't work and changing the column would require a long time so, for now, LC-MS is not an option. HPLC could be an option but the machine I dispose of is...

03 March 2016 6,650 4 View