Elution of Metronidazole and Gentamicin from Polymethylmethacrylate Beads

Abstract

(ABSTRACT)Ten polymethylmethacrylate (PMMA) beads containing metronidazole (3 concentrations); gentamicin sulfate; or metronidazole and gentamicin sulfate were immersed in 5 ml of phosphate buffered saline in triplicate. Eluent was replaced at specified time intervals for 1 day (1, 3, 6, 12 and 24 hours), daily, or weekly for 21 days.Antibiotic concentrations were measured by High Performance Liquid Chromatography.Changes in antibiotic bioactivity attributable to polymerization or co-polymerization of the antibiotics with PMMA, ethylene oxide sterilization, and storage of antibioticimpregnated PMMA (AIPMMA) beads containing metronidazole were evaluated.Antibiotic elution patterns were similar for all groups. Day-1 elution for groups containing either metronidazole (3 concentrations) or gentamicin represented a mean 63% to 66% and 79% respectively of the 21-day total elution. Approximately 50% of the day-1 elution occurred during the first hour. The elution of metronidazole was dosedependent. There was no significant difference in the total amount of antibiotic eluted from groups that had the saline changed daily versus weekly. The elution of metronidazole (day 3-21) and gentamicin (all days) was significantly greater when metronidazole and gentamicin were combined (p<0.05). Polymerization of PMMA was delayed in groups containing metronidazole.Neither polymerization nor copolymerization of metronidazole and gentamicin with PMMA, gas-sterilization, or 2-month storage of beads containing metronidazole significantly affected antimicrobial bioactivity.Metronidazole elutes from PMMA. The frequency at which the saline was changed did not affect the rate of antibiotic elution.

Evaluation of in vitro serial antibiotic elution from meropenem-impregnated polymethylmethacrylate beads after ethylene oxide gas and autoclave sterilization

“…55,56,57 Ramos et al reported that neither polymerization, gas sterilization, nor 2 month storage of AIPMMA with varied antibiotics affected the bioactivity of the antibiotic against a common pathogen. 10 In our study the MRT did differ significantly, suggesting that ethylene oxide sterilization resulted in slightly longer elution time, though there would likely be no clinical significance in this increase (7 hours).…”

“…Meropenem's elution pattern is biphasic, which is similar to patterns reported for other antibiotics. 10 This biphasic elution is suspected to be the result of initial antibiotic elution from the surface of the bead and a sustained release during the second phase of elution from the bead matrix. 54 Approximately 40% of the cumulative antibiotic elution occurred during the first hour.…”

“…Although this finding was not statistically significant it suggests that a higher success rate could be achieved with a treatment combination. 10 Prefabrication of antibiotic beads and gas sterilization for "off the shelf" availability has been reported, but no product has been approved for commercial use in the United…”

Newer Methods of Nanoparticle Synthesis: Nitroimidazole properties with Nanometal oxides in Polymer Cages as Drug-Biomarker Monitors

“…Nitroimidazole polymer complexes as hydrogels, beads used as colon targeted drug delivery systems is emerging [1,3,6,11,13,14,15,17,22]. Different polymers such as polyethylene glycol [9,20], poly vinyl alcohol [4,24], polymethylmethacrylate [16],polysaccharides [6,11]. Other uses of nitroimidazole polymer complexes as delivery systems are reported in periodontal diseases [2,21], amebiasis [6,13,22], helicobector pylori [7], gentamycin [16], vaginitis [8], gastritis [10,12], sprays [19], liposomes [25].…”

“…Of mention, gentamycin, helicobector pylori and amoeba microbes have been found as potential candidates as targeted nitroimidazole delivery [7,16,22]. Other options of liposomes as nitroimidazole delivery systems have been reported as minicapsular extrusion system [25].…”