Anderson Erin M, Noble Misty L, Garty Shai, Ma Hongyan, Bryers James D, Shen Tueng T, Ratner Buddy D
Dept. of Bioengineering, University of Washington, Seattle, WA 98195, USA.
Biomaterials. 2009 Oct;30(29):5675-81. doi: 10.1016/j.biomaterials.2009.06.047. Epub 2009 Jul 23.
Intraocular lens implantation after opacified natural lens removal is the primary treatment for cataracts in developed countries. Cataract surgery is generally considered safe, but entails significant risks in countries where sophisticated sterile operating theaters are not widely available. Post-operative infection (endophthalmitis) is a potential blinding complication. Infection often results from bacterial colonization of the new lens implant and subsequent antibiotic-tolerant biofilm formation. To combat this risk, we developed a polymeric hydrogel system that can deliver effective levels of antibiotic over an extended period of time within the globe of the eye. Norfloxacin antibiotic was loaded into cross-linked poly(2-hydroxyethyl methacrylate) (pHEMA) gels, which were subsequently surface-modified with octadecyl isocyanate to produce a hydrophobic rate-limiting barrier controlling norfloxacin release. Octadecyl surface modification was characterized using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). A 15-min modification leads to a uniform surface coating and near zero order release of norfloxacin from the matrix. Norfloxacin released from coated pHEMA kills Staphylococcus epidermidis in suspension and on a simulated medical implant surface. With these data, we demonstrate a new and effective system for sustained drug release from a hydrogel matrix with specific application for intraocular lens surgery.
在发达国家，摘除混浊的天然晶状体后植入人工晶状体是治疗白内障的主要方法。白内障手术一般被认为是安全的，但在没有广泛配备先进无菌手术室的国家，该手术存在重大风险。术后感染（眼内炎）是一种潜在的致盲并发症。感染通常源于新植入晶状体的细菌定植以及随后形成的耐抗生素生物膜。为应对这种风险，我们开发了一种聚合物水凝胶系统，它能够在眼球内长时间递送有效剂量的抗生素。将诺氟沙星抗生素载入交联聚甲基丙烯酸2-羟乙酯（pHEMA）凝胶中，随后用异氰酸十八酯对其进行表面改性，以形成控制诺氟沙星释放的疏水限速屏障。使用扫描电子显微镜（SEM）和X射线光电子能谱（XPS）对十八烷基表面改性进行表征。15分钟的改性导致形成均匀的表面涂层，且诺氟沙星从基质中近乎零级释放。从包被的pHEMA释放的诺氟沙星可杀死悬浮液中和模拟医用植入物表面的表皮葡萄球菌。基于这些数据，我们展示了一种新型有效的系统，可实现水凝胶基质的持续药物释放，并特别适用于人工晶状体手术。
