Liawrungrueang Wongthawat, Ungphaiboon Suwipa, Jitsurong Arnurai, Ingviya Natnicha, Tangtrakulwanich Boonsin, Yuenyongviwat Varah
Department of Orthopedics, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, 90110, Thailand.
Department of Pharmaceutical Technology, Faculty of Pharmaceutical Science, Prince of Songkla University, Hat Yai, Thailand.
BMC Musculoskelet Disord. 2021 Jan 4;22(1):5. doi: 10.1186/s12891-020-03923-w.
Antibiotic-loaded bone cement, or antibiotic-impregnated polymethylmethacrylate (PMMA), were developed to prevent and treat bone and joint infections. Gentamicin is an antibiotic that is commonly used in combination with PMMA; however, gentamicin powder is hard to obtain in many countries. This study aimed to evaluate the elution characteristics of gentamicin-impregnated PMMA made with lyophilized liquid gentamicin, compared with PMMA; which is made from commercial gentamicin powder.
The experimental sample was divided into 2 groups: the gentamicin power group (PG-PMMA) and the lyophilized liquid gentamicin group (LG-PMMA). Ten cement spacers were prepared in each group. These were produced by mixing gentamicin powder, or lyophilized liquid gentamicin, with a powder polymer before adding the liquid monomer (2 g of gentamicin and 40 g of PMMA). The volume and surface area of the antibiotic-impregnated cement spacers were 50 cm and 110 cm, respectively. Each spacer was immersed in phosphate-buffered saline, which was changed daily under sterile conditions. The solutions were collected to measure the level of gentamicin using the enzyme multiplied immunoassay technique (EMIT), at days 1, 2, 3, 4, 5, 6, 7, 14, 21, 28, 35 and 42.
The collections from both groups had high concentrations of gentamicin on day 1 (113.63 ± 23.42 mg/dL in LG-PMMA and 61.7 ±8.37 mg/dL in PG-PMMA), but experienced a continuous decrease over time. The PMMA spacers from both groups could release gentamicin for up to 6 weeks (3.28 ± 1.17 mg/dL in LG-PMMA and 1.21 ± 0.28 mg/dL in PG-PMMA). However, there were significantly higher levels of gentamicin concentrations in the LG-PMMA group compared to the PG-PMMA group at all time points (P< 0.05).
Gentamicin-impregnated PMMA made with lyophilized liquid gentamicin had approximately a two times higher rate of antibiotic elution in preliminary in vitro studies, as compared with PMMA made with premixed gentamicin powder.
载抗生素骨水泥，即抗生素浸渍聚甲基丙烯酸甲酯（PMMA），被开发用于预防和治疗骨与关节感染。庆大霉素是一种常与PMMA联合使用的抗生素；然而，在许多国家庆大霉素粉末难以获取。本研究旨在评估与由市售庆大霉素粉末制成的PMMA相比，用冻干液态庆大霉素制成的庆大霉素浸渍PMMA的洗脱特性。
实验样本分为2组：庆大霉素粉末组（PG-PMMA）和冻干液态庆大霉素组（LG-PMMA）。每组制备10个骨水泥间隔物。这些是通过在加入液态单体之前将庆大霉素粉末或冻干液态庆大霉素与粉末状聚合物混合制成的（2克庆大霉素和40克PMMA）。载抗生素骨水泥间隔物的体积和表面积分别为50立方厘米和110平方厘米。每个间隔物浸入磷酸盐缓冲盐水中，在无菌条件下每天更换。在第1、2、3、4、5、6、7、14、21、28、35和42天收集溶液，使用酶放大免疫分析技术（EMIT）测量庆大霉素水平。
两组在第1天的收集液中庆大霉素浓度都很高（LG-PMMA组为113.63±23.42毫克/分升，PG-PMMA组为61.7±8.37毫克/分升），但随着时间持续下降。两组的PMMA间隔物都可释放庆大霉素长达6周（LG-PMMA组为3.28±1.17毫克/分升，PG-PMMA组为1.21±0.28毫克/分升）。然而，在所有时间点，LG-PMMA组的庆大霉素浓度水平均显著高于PG-PMMA组（P<0.05）。
在初步体外研究中，与用预混庆大霉素粉末制成的PMMA相比，用冻干液态庆大霉素制成的庆大霉素浸渍PMMA的抗生素洗脱率大约高出两倍。
