Zinc monoglycerolate--a slow-release source of therapeutic zinc: solubilization by endogenous ligands.
A combination of 65Zn-tracer determinations, oxidative analyses for glycerol, and a bioassay for uncomplexed Zn2+ have shown that: (i) zinc monoglycerolate (ZMG) dissolves in aqueous salt solutions/physiological media by dissociation into zinc ions and glycerol, but the rate and extent of ZMG dissolution depend upon pH, and/or concentration and complexing efficiency of zinc-ligands; (ii) under physiological conditions certain ligands present in skin and blood (e.g. citrate, lactate, albumin, histidine, glutathione and other thiols and, to a lesser extent, amino acids) accelerate ZMG dissolution; and (iii) there is a general correlation between the conditional stability constants (pH 7.3, 25 degrees C) of zinc-ligand complexes and the ability of given ligands to (a) solubilize ZMG in vitro and (b) mask the irritancy of Zn2+ in vivo. These observations indicate a mechanism for the transformation of ZMG applied transdermally or subcutaneously, to bioactive zinc (anti-arthritic nutritional supplement, etc.).
Fairlie
D P
DP
Department of Pathology, University of Adelaide, South Australia.
Whitehouse
M W
MW
Taylor
R M
RM
D000818:Animals; D055598:Chemical Phenomena; D002626:Chemistry, Pharmaceutical; D002627:Chemistry, Physical; D003692:Delayed-Action Preparations; D005260:Female; D005990:Glycerol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D006863:Hydrogen-Ion Concentration; D007509:Irritants; D008024:Ligands; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D051381:Rats; D012995:Solubility; D015032:Zinc / Q000493:pharmacokinetics; D015037:Zinc Radioisotopes
D003692:Delayed-Action Preparations; D007509:Irritants; D008024:Ligands; D009942:Organometallic Compounds; D015037:Zinc Radioisotopes; C067226:zinc monoglycerolate; D015032:Zinc; D005990:Glycerol