title: Influence of the Molecular Weight and Charge of Antibiotics on Their Release Kinetics From Gelatin Nanospheres.
abstract: In this study, we investigated the fundamental relationship between the physicochemical characteristics of antibiotics and the kinetics of their release from gelatin nanospheres. We observed that antibiotics of high molecular weight (colistin and vancomycin) were released in a sustained manner from oppositely charged gelatin carriers for more than 14 d, as opposed to antibiotics of low molecular weight (gentamicin and moxifloxacin) which were released in a burst-like manner. The release kinetics of positively charged colistin strongly correlated with the rate of the enzymatic degradation of gelatin. To elucidate the differences among release kinetics of antibiotics, we explored the mechanism of interactions between antibiotics and gelatin nanospheres by monitoring the kinetics of release of antibiotics as a function of pH, ionic strength, and detergent concentrations. These studies revealed that the interactions between antibiotics and gelatin nanospheres were mainly dominated by (i) strong electrostatic forces for colistin; (ii) strong hydrophobic and electrostatic forces for vancomycin; (iii) weak electrostatic and hydrophobic forces for gentamicin; and (iv) weak hydrophobic forces for moxifloxacin. These results confirm that release of antibiotics from gelatin nanospheres strongly depends on the physicochemical characteristics of the antibiotics.
authors.affiliation: Department of Biomaterials, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Jiankang
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Orthopedic Surgery, Laboratory for Experimental Orthopedics, CAPHRI School for Public Health and Primary Care, Maastricht University Medical Centre, The Netherlands.
authors.forename: Jim C E
authors.initials: JC
authors.lastname: Odekerken
authors.affiliation: Department of Bio-Organic Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, The Netherlands.
authors.forename: Dennis W P M
authors.initials: DW
authors.lastname: Löwik
authors.affiliation: Department of Biomaterials, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Paula M
authors.initials: PM
authors.lastname: López-Pérez
authors.affiliation: Department of Orthopedic Surgery, Laboratory for Experimental Orthopedics, CAPHRI School for Public Health and Primary Care, Maastricht University Medical Centre, The Netherlands.
authors.forename: Tim J M
authors.initials: TJ
authors.lastname: Welting
authors.affiliation: Department of Biomaterials, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Fang
authors.initials: F
authors.lastname: Yang
authors.affiliation: Department of Biomaterials, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: John A
authors.initials: JA
authors.lastname: Jansen
authors.affiliation: Department of Biomaterials, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands. sander.leeuwenburgh@radboudumc.nl.
authors.forename: Sander C G
authors.initials: SC
authors.lastname: Leeuwenburgh
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000493:pharmacokinetics*; D065546:Drug Liberation; D005780:Gelatin; D057927:Hydrophobic and Hydrophilic Interactions; D008970:Molecular Weight; D054118:Nanospheres / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D000900:Anti-Bacterial Agents; D005780:Gelatin
keywords: antibiotics; bone infection; controlled release; gelatin nanospheres