A molecular dynamics (MD) computer simulation study is presented for the solvation of purine alkaloids (caffeine, theophylline, and theobromine) in supercritical CO2 at 313 K and density in the range 0.117-0.94 g/cm(3) using force fields that treat all atoms explicitly. The work discusses the local density augmentation effect in these systems and provides molecular-level details for the solvent density maps around each solute for different pressures. (c) 2004 Elsevier B.V. All rights reserved.