title: Using water-solvent systems to estimate in vivo blood-tissue partition coefficients.
abstract: BACKGROUND
  Blood-tissue partition coefficients indicate how a chemical will distribute throughout the body and are an important part of any pharmacokinetic study. They can be used to assess potential toxicological effects from exposure to chemicals and the efficacy of potential novel drugs designed to target certain organs or the central nervous system. In vivo measurement of blood-tissue partition coefficients is often complicated, time-consuming, and relatively expensive, so developing in vitro systems that approximate in vivo ones is desirable. We have determined such systems for tissues such as brain, muscle, liver, lung, kidney, heart, skin, and fat.
  
  
  RESULTS
  Several good (p < 0.05) blood-tissue partition coefficient models were developed using a single water-solvent system. These include blood-brain, blood-lung, blood-heart, blood-fat, blood-skin, water-skin, and skin permeation. Many of these partition coefficients have multiple water-solvent systems that can be used as models. Several solvents-methylcyclohexane, 1,9-decadiene, and 2,2,2-trifluoroethanol-were common to multiple models and thus a single measurement can be used to estimate multiple blood-tissue partition coefficients. A few blood-tissue systems require a combination of two water-solvent partition coefficient measurements to model well (p < 0.01), namely: blood-muscle: chloroform and dibutyl ether, blood-liver: N-methyl-2-piperidone and ethanol/water (60:40) volume, and blood-kidney: DMSO and ethanol/water (20:80) volume.
  
  
  CONCLUSIONS
  In vivo blood-tissue partition coefficients can be easily estimated through water-solvent partition coefficient measurements.Graphical abstract:Predicted blood-brain barrier partition coefficients coloured by measured log BB value.
authors.affiliation: Computing and Mathematics Department, Oral Roberts University, Tulsa, OK 74171 USA.
authors.forename: Caitlin E
authors.initials: CE
authors.lastname: Derricott
authors.affiliation: Computing and Mathematics Department, Oral Roberts University, Tulsa, OK 74171 USA.
authors.forename: Emily A
authors.initials: EA
authors.lastname: Knight
authors.affiliation: Department of Chemistry, University of North Texas, 1155 Union Cir, Denton, TX 76203 USA.
authors.forename: William E
authors.initials: WE
authors.lastname: Acree
authors.affiliation: Computing and Mathematics Department, Oral Roberts University, Tulsa, OK 74171 USA.
authors.forename: Andrew Sid
authors.initials: AS
authors.lastname: Lang
keywords: Abraham model; Blood–brain barrier; Blood–tissue partition coefficients; Pharmacokinetics