
Hyaluronic acid does not hold a thousand times its weight in water - apsec112
https://www.oumere.com/blogs/news/hyaluronic-acid-does-not-hold-1000-times-its-weight-in-water-not-even-close
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MoZeus
This is on the commercial website of a company that wants me to buy their non-
HA containing $150/bottle eye serum.

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eghad
Not only that, but the assumptions are poor to begin with. Most skincare
products containing sodium hyaluronate are either micronized or in a
crosspolymer so that it can penetrate the skin, not HA on its own (something
I'd expect a chemist/dermatologist to know). Cursory googling it seems the
writer/owner was attaching her name to reddit submissions of scientific
articles unrelated to her to game SEO and give her credibility that it it's
painfully obvious she doesn't have.

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b34r
“Daltons are used to measure something very low in mass”

Why not just use nanograms or picograms?

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b34r
Apparently picograms are still orders of magnitude bigger and thus not useful
for this type of measurement. Science!

Looking further into it, yoctagrams or zetograms would be small enough to
express the measurement. I suspect daltons are used because they’re pegged to
a 1/12 of a carbon atom and that makes the math easier to reason about or
something like that.

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dmurray
Yeah, one Dalton = one neutron or one proton [0], so it's a convenient unit if
you're literally adding up atomic weights to find the weight of a single
molecule.

[0] This is true for chemists, but not for physicists, who pay more attention
to the mass defect rounding error.

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contravariant
To expand on that, for physicists Carbon-12 is exactly 12 daltons also denoted
12 Da or 12 u. All other isotopes deviate slightly from a whole number of
daltons. If I recall correctly the number of nucleons minus the daltons
continues to decrease until you get to iron, which has the lowest nuclear
binding energy, after which it continues to increase again (although there's
some variation between isotopes so this is more of a general trend).

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dmurray
And that's why you can have nuclear power either from combining really small
atoms (fusion) or splitting big ones (fission) but nobody would propose a
nuclear reactor that runs on iron?

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mimac
I skimmed the article and I think the author should have used CaCl2 to improve
the gelling strenght. Ca-alginate which is comparable in structure forms gels
in very low concentrations when Ca ions are present.

