Re: MIT 3D printed key components of mass-spectrometer

On 08/04/2024 15:28, John Larkin wrote:

On Mon, 8 Apr 2024 10:23:24 +0100, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
 

On 08/04/2024 05:47, Jan Panteltje wrote:

Researchers 3D print key components for a point-of-care mass spectrometer
   https://www.sciencedaily.com/releases/2024/04/240404113429.htm
pdf:
   https://pubs.acs.org/doi/10.1021/jasms.3c00409
>
Massachusetts Institute of Technology
Summary:
Researchers 3D printed a miniature ionizer, a key component of a mass spectrometer. Their device could someday enable an affordable, in-home mass spectrometer for health monitoring.

>
It is complete nonsense. Making the hard vacuum needed for ions to move
freely in mass spectrometry and sample handling to introduce the sample
into the unit without losing vacuum are fundamentals that won't go away.
>
The closest to a quick dirt cheap MS is time of flight laser ablation if
your sample is a solid or can be put on one. Liquid samples are really
messy and water vapour is the bane of vacuum systems.
>
Selective ion probes offer a much better alternative for bio samples (I
suppose the MIT PR department has to justify its existence somehow).

 I'd expect 3D printed stuff to outgas forever.

Some of the exotic very crosslinked UV polymers from resin baths might not outgas but the sintered stuff would be very problematic. Using 3D printing for a variant of lost wax metal casting would be OK though.
Back when I was involved the only polymers allowed in hard vacuum were PTFE (which creeps) and PEEK (which is a good engineering plastic). Nothing else could stand up to the aggressive baking procedures needed to dry them out to hard vacuum.

 3D is super slow, too. I've heard of modestly complex parts taking
days to fab. The upside is that it can make things that are impossible
to machine or mold.

My favourite toy demo on 3D printers is a digital sundial which shows the time in a 7 segment style display with 10 minute resolution. Adjusting it for summertime is a trivial rotation.
--
Martin Brown