title: Elution profiles of tobramycin and vancomycin from high-purity calcium sulphate beads incubated in a range of simulated body fluids.
abstract: The aim of this study was to characterise the elution profiles of antibiotics in combination with pharmaceutical grade calcium sulphate beads in phosphate buffered saline and other physiological solutions which more closely mimic the in vivo environment. Synthetic recrystallised calcium sulphate was combined with vancomycin hydrochloride powder and tobramycin sulphate solution and the paste was formed into 3 mm diameter hemispherical beads. Then 2 g of beads were immersed in 2 ml of either phosphate buffered saline, Dulbecco's Modified Eagle Medium or Hartmann's solution and incubated at 37℃ for up to 21 days. At a range of time points, eluent was removed for analysis by liquid chromatography-mass spectrometry (LC-MS). Tobramycin sulphate and vancomycin hydrochloride release was successfully quantified against standard curves from solutions eluted in all three physiological media (phosphate buffered saline, Dulbecco's Modified Eagle Medium and Hartmann's solution) during incubation with calcium sulphate beads. One hour eluate concentrations were high, up to 2602 µg/ml for tobramycin in phosphate buffered saline and 7417 µg/ml for vancomycin, whereas in DMEM, the levels of tobramycin were 2458 µg/ml and 4401 µg/ml for vancomycin. The levels in HRT were 2354 µg/ml for tobramycin and 5948 µg/ml for vancomycin. The results show highest levels of antibiotic elution over the first 24 h, which gradually diminish over the following 21 days.
authors: Biocomposites Ltd., Keele Science Park, Staffordshire, UK.
authors: J J
authors: JJ
authors: Cooper
authors: Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, UK Exeter Mass Spectrometry Facility, Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
authors: H
authors: H
authors: Florance
authors: Biocomposites Ltd., Keele Science Park, Staffordshire, UK.
authors: J L
authors: JL
authors: McKinnon
authors: Biocomposites Ltd., Keele Science Park, Staffordshire, UK pl@biocomposites.com.
authors: P A
authors: PA
authors: Laycock
authors: Biocomposites Ltd., Keele Science Park, Staffordshire, UK.
authors: S S
authors: SS
authors: Aiken
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000737:chemistry; D040761:Biomimetic Materials / Q000737:chemistry; D001826:Body Fluids / Q000737:chemistry*; D002133:Calcium Sulfate / Q000737:chemistry*; D004058:Diffusion; D004343:Drug Implants / Q000008:administration & dosage / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D014031:Tobramycin / Q000008:administration & dosage / Q000737:chemistry*; D014640:Vancomycin / Q000008:administration & dosage / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D004343:Drug Implants; D014640:Vancomycin; D014031:Tobramycin; D002133:Calcium Sulfate
keywords: Antibiotics; calcium sulphate; elution