Ramos Jose R, Howard Rick D, Pleasant R Scott, Moll H David, Blodgett Dennis J, Magnin Geraldine, Inzana Thomas J
Department of Large Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Vet Surg. 2003 May-Jun;32(3):251-61. doi: 10.1053/jvet.2003.50024.
To characterize the elution and bioactivity of metronidazole and gentamicin sulfate polymerized, individually and in combination, with polymethylmethacrylate (PMMA).
In vitro experimental study.
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 or 21 days, and antibiotic concentrations were measured by high-performance liquid chromatography. Changes in antibiotic bioactivity attributable to polymerization or copolymerization of the antibiotics with PMMA, ethylene oxide sterilization, and storage of AIPMMA beads containing metronidazole were evaluated.
Antibiotic elution patterns were similar for all groups. Day 1 elution for groups containing metronidazole or gentamicin individually represented a mean 63%-66% and 79%, respectively, of the 21-day total. Approximately 50% of the day 1 elution occurred during the first hour. The elution of metronidazole was dose dependent. The elution of metronidazole (day 3-21) and gentamicin (all days) was significantly greater when metronidazole and gentamicin were combined (P <.05). The addition of metronidazole delayed polymerization of PMMA. 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 elution from PMMA was dose dependent. Copolymerization of metronidazole and gentamicin sulfate in PMMA resulted in increased rates of elution. Intraoperative preparation of metronidazole-impregnated PMMA beads is not practical, but sterilization and storage for 2 months should not affect efficacy.
The local delivery of biologically active metronidazole and gentamicin by elution from PMMA is feasible.
分别及联合表征甲硝唑和硫酸庆大霉素与聚甲基丙烯酸甲酯（PMMA）聚合后的洗脱情况及生物活性。
体外实验研究。
含甲硝唑（3种浓度）、硫酸庆大霉素或甲硝唑与硫酸庆大霉素的PMMA珠粒一式三份浸入5 mL磷酸盐缓冲盐水中。在指定时间间隔更换洗脱液，持续1天或21天，并用高效液相色谱法测量抗生素浓度。评估了抗生素与PMMA聚合或共聚、环氧乙烷灭菌以及含甲硝唑的AIPMMA珠粒储存对抗生素生物活性的影响。
所有组的抗生素洗脱模式相似。含甲硝唑或硫酸庆大霉素的组在第1天的洗脱量分别平均占21天总量的63% - 66%和79%。约50%的第1天洗脱发生在最初1小时内。甲硝唑的洗脱呈剂量依赖性。当甲硝唑和硫酸庆大霉素联合使用时，甲硝唑（第3 - 21天）和庆大霉素（所有天数）的洗脱量显著增加（P <.05）。甲硝唑的添加延迟了PMMA的聚合。甲硝唑和硫酸庆大霉素与PMMA的聚合或共聚、气体灭菌或含甲硝唑珠粒储存2个月均未显著影响抗菌生物活性。
PMMA中甲硝唑的洗脱呈剂量依赖性。甲硝唑和硫酸庆大霉素在PMMA中共聚导致洗脱率增加。术中制备含甲硝唑的PMMA珠粒不实用，但灭菌和储存2个月不应影响疗效。
通过从PMMA中洗脱进行生物活性甲硝唑和庆大霉素的局部递送是可行的。
