Release of vancomycin and teicoplanin from a plasticized and resorbable gelatin sponge: in vitro investigation of a new antibiotic delivery system with glycopeptides.
BACKGROUND
The aim of this study was to evaluate the efficacy of sustained release of vancomycin and teicoplanin from a resorbable gelatin glycerol sponge, in order to establish a new delivery system for local anti-infective therapy.


METHODS
60 plasticized glycerol gelatin sponges containing either 10 or 20% gelatin (w/v) were incubated in vancomycin or teicoplanin solution at 20 degrees C for either 1 or 24 h. In vitro release properties of the sponges were investigated over a period of 1 week by determining the levels of vancomycin and teicoplanin eluted in plasma using fluorescent polarization immunoassay. The rate constant and the half-life for the antibiotic release of each group were calculated by linear regression assuming first order kinetics.


RESULTS
Presoaking for 24 h was associated with a significant increase in the total antibiotic release in all groups opposed to 1 h of incubation, except for the 10% sponges presoaked in teicoplanin. Doubling the gelatin content of the sponges from 10 to 20% significantly increased the total release of antibiotic load only in teicoplanin-containing sponges after 24 h incubation. In all corresponding groups investigated, release of vancomycin was more prolonged compared to teicoplanin, which allowed a gradual release beyond 5 days. The half-life (h +/- SEM) of both types of vancomycin-containing sponges was significantly prolonged by 24 h incubation in comparison to 1 h incubation (29.1 +/- 5.9 vs 5.9 +/- 1.0; p < 0.001, 30.0 +/- 2.1 vs 11.1 +/- 1.9; p < 0.001). However, neither doubling the gelatin content of the sponges nor a prolonged incubation was associated with a significantly prolonged delivery of teicoplanin.


CONCLUSIONS
This study demonstrated a better diffusion-controlled release of vancomycin-impregnated glycerol gelatin sponges compared to those pretreated with teicoplanin. The plasticized glycerol gelatin sponge may be a promising carrier for the application of vancomycin to infected wounds for local anti-infective therapy.
Drognitz
O
O
Universitätsklinikum Freiburg, Klinik und Poliklinik für Chirurgie, Abteilung für Allgemein- und Viszeralchirurgie, Hugstetter Str. 55, 79106 Freiburg i. Brsg., Germany. oliverdrognitz@web.de
Thorn
D
D
Krüger
T
T
Gatermann
S G
SG
Iven
H
H
Bruch
H-P
HP
Muhl
E
E
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems / Q000379:methods*; D005780:Gelatin / Q000737:chemistry*; D006020:Glycopeptides / Q000008:administration & dosage / Q000493:pharmacokinetics; D006207:Half-Life; D010969:Plastics / Q000737:chemistry; D017334:Teicoplanin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D014640:Vancomycin / Q000008:administration & dosage / Q000493:pharmacokinetics*
D000900:Anti-Bacterial Agents; D003692:Delayed-Action Preparations; D006020:Glycopeptides; D010969:Plastics; D017334:Teicoplanin; D014640:Vancomycin; D005780:Gelatin