I'm seeing a pattern here. Just as with vanadium, other molecules like zinc, quercetin, etc... aren't water soluble or dissolve poorly in water. Usually these will dissolve well with alcohol, from what I've read.
If you buy some supplement, be sure that you buy an organically chelated one, that means, one that is bound to an organic molecule. That will make those molecular compounds water soluble. They will be a lot better absorbed than their pure counterparts, depending on your absorption effectiveness and the compounded organic molecule up to 20x better absorption.
Hydorphobic means "fear from water", like all cats excepting tigers.
And hydrophylic is the opposite "loves water". Stuff that is hydrophylic will be better absorbed by our bodies.
A little list of some substances and their solubility I've found while googling around:
Vanadium/Vanadyl Sulfate = hydrophobic
BMOV, BEOV, BPOV, BAOV = hydrophylic
Zink = hydrophobic (depending on temperature and/or PH)
Zink gluconate = hydrophylic
Chromium = mostly hydrophobic
Chromium hexavalent salts = hydrophylic (WARNING! CARCERIGENOUS!)
Chromium trivalent salts = hydrophylic (WARNING! POSSIBLY CARCERIGENOUS!)
Chromium Picolinate = hydrophylic/fat soluble (The best combo you can have)
resveratrol = hydrophobic / alcohol soluble
resveradox(tm) = hydrophylic
quercetin = hydrophobic
bio-quercetin = hydrophylic
L-Carnitine = hydrophylic
Biotin = hydrophylic
Benfotiamine = fat soluble
Aminoguanidine = hydrophylic
You can say that hydrophylic will be better absorbed into the bloodstream and fat soluble will easily penetrate the cells.
The literature that I've read so far suggests that; if you're looking for a special supplement, make sure that it is either fat soluble or hydrophylic (water soluble)
AND NOT TOXIC, like with the chromium example, where one molecule may be ineffective the other may be effective but toxic. If you get the hydrophobic one, look if it is alcohol soluble, but then you have to pour the powder into some alcohol and drink it, to get enough of the substance into your bloodstream to see any effect.