Jian Yihui, Zhu Yufang
School of Materials and Chemistry, University of Shanghai for Science and Technology, Shanghai 200093, China.
AccuPath Medical (Jiaxing) Co., Ltd., Jiaxing 314006, China.
Polymers (Basel). 2022 Jul 26;14(15):3018. doi: 10.3390/polym14153018.
Drug-eluting stents (DES) have become the main method of interventional therapy for coronary heart disease, because their drug coating can effectively reduce the incidence of restenosis after stent implantation. Biodegradable polymers for coatings are the latest development direction for coating polymers, because they can be degraded into small molecules in the human body. In this study, the polymer P34HB(P34HB-1:4HB% = 1 mol%, Mw: 225,000; P34HB-10:4HB% = 10 mol%, Mw: 182,000), the fourth generation of biodegradable Polyhydroxy alkanoates (PHAs), was coated on stents to evaluate the drug release properties of the DES. Both P34HB-1 and P34HB-10 coatings showed increased drug release rates, as the polymer concentrations were gradually increased from 8 mg/mL to 28 mg/mL. Both P34HB-1 and P34HB-10 coatings showed increased drug release rates as the drug polymer ratios were gradually changed from 1:10 to 1:2. The drug release rates of the P34HB-1 coatings became slower than P34HB-10, thus showing sustained drug release effects. The drug release rates of the P34HB-1 coatings decreased when Rates of solution flow increased, decreased when Focusing pressures decreased, and decreased when Mandrel moving speeds increased. P34HB-1 coatings prepared with CHCl/NPA (10:1) mixed solvents had better controlled drug release rates compared to Firebird2. The drug release rates of P34HB-1 coatings prepared with CHCl solutions decreased as the outer layer weights were increased from 0 to 800 μg. When the outer layer weights reached 800 μg, the drug release rates of P34HB-1 coatings were slower than Firebird2. P34HB-1 coatings prepared with both CHCl/NPA (10:1) mixed solvents and double layers had more effectively controlled drug release rates than P34HB-1 coatings prepared with only mixed solvents or double layers and these effects were far greater than Firebird2; thus, P34HB-1 represents a latent polymer for DES.
药物洗脱支架（DES）已成为冠心病介入治疗的主要方法，因为其药物涂层可有效降低支架植入后再狭窄的发生率。用于涂层的可生物降解聚合物是涂层聚合物的最新发展方向，因为它们可在人体内降解为小分子。在本研究中，将第四代可生物降解聚羟基脂肪酸酯（PHA）聚合物P34HB（P34HB - 1：4HB% = 1摩尔%，Mw：225,000；P34HB - 10：4HB% = 10摩尔%，Mw：182,000）涂覆在支架上，以评估药物洗脱支架的药物释放特性。随着聚合物浓度从8mg/mL逐渐增加至28mg/mL，P34HB - 1和P34HB - 10涂层的药物释放速率均增加。随着药物与聚合物比例从1：10逐渐变为1：2，P34HB - 1和P34HB - 10涂层的药物释放速率均增加。P34HB - 1涂层的药物释放速率比P34HB - 10慢，从而显示出药物缓释效果。当溶液流速增加时，P34HB - 1涂层的药物释放速率降低；当聚焦压力降低时，药物释放速率降低；当芯轴移动速度增加时，药物释放速率降低。与Firebird2相比，用CHCl/NPA（10：1）混合溶剂制备的P34HB - 1涂层对药物释放速率的控制更好。当外层重量从0增加到800μg时，用CHCl溶液制备的P34HB - 1涂层的药物释放速率降低。当外层重量达到800μg时，P34HB - 1涂层的药物释放速率比Firebird2慢。用CHCl/NPA（10：1）混合溶剂和双层制备的P34HB - 1涂层比仅用混合溶剂或双层制备的P34HB - 1涂层更有效地控制了药物释放速率，且这些效果远优于Firebird2；因此，P34HB - 1是一种潜在的药物洗脱支架聚合物。
