Plasticizers in polyvinyl chloride (PVC) are not covalently bound to the polymer and can thus migrate into the contact medium. The presented study investigated the potential effects of phospholipid-lining as anti-coagulation coating(s) (ACC) on the migration rate of plasticizers from PVC tubing into blood.

For the in-vitro study, five different groups of tubing sets in six replicates were perfused with sheep blood (Group A: PVC plasticized with di-(2-ethylhexyl) phthalate (DEHP) without ACC, Group B: DEHP-plasticized PVC with ACC, Group C: PVC plasticized with tri-(2-ethylhexyl) trimellitate (TOTM) without ACC, Group D: TOTM-plasticized PVC with ACC, Group E (control group): polyolefin material with ACC but without plasticizers). Both the levels of the unchanged plasticizers in blood and the concentration levels of their primary degradation products were assessed. For DEHP, the primary metabolite MEHP (mono-(2-ethylhexyl) phthalate) was determined. The isomers of MEHTM (mono-(2-ethylhexyl) trimellitate) and DEHTM (di-(2-ethylhexyl) trimellitate), respectively, were investigated as primary metabolites of TOTM.

The calculated DEHP equivalents (sum of determined levels of DEHP and MEHP) after 24 h of perfusion displayed a tendency towards lower levels in the tubing sets without ACC (Group A (201 ± 56.4 µmol/L)) compared to the tubing sets with ACC (Group B (253 ± 369 µmol/L)). Significantly different DEHP equivalents between Group A and Group B were found after a perfusion time of 6 h and 10 h, respectively. A similar effect was observed for the TOTM-containing tubing sets. However, the absolute plasticizer migration rate of TOTM (TOTM equivalents) after 24 h of perfusion was found to be significantly lower compared to that of DEHP (with a factor of over 200).

The results indicate that phospholipid coating (ACC) rather enhances the migration of plasticizers and of their primary degradation products from PVC tubing into streaming blood. The enhancement effect was found to be slightly greater for TOTM, but as TOTM migrates in significantly lower levels than DEHP in all experimental settings, TOTM is confirmed to be a recommendable alternative plasticizer to DEHP in medical devices.

聚氯乙烯（PVC）中的增塑剂未与聚合物共价键合，因此可以迁移到接触介质中。本研究调查了磷脂衬里作为抗凝涂层（ACC）对增塑剂从PVC管到血液的迁移速率的潜在影响。

对于体外研究，用羊血灌注六组重复的五组不同的油管组（A组：不含ACC的邻苯二甲酸二-（2-乙基己基）邻苯二甲酸酯（DEHP）增塑的PVC，B组：含ACC的DEHP增塑的PVC ACC，C组：用不带ACC的三（2-乙基己基）偏苯三酸酯（TOTM）增塑的PVC，D组：带ACC的TOTM增塑的PVC，E组（对照组）：带ACC但无增塑剂的聚烯烃材料。评估了血液中不变的增塑剂的水平及其主要降解产物的浓度水平。对于DEHP，测定了主要代谢物MEHP（邻苯二甲酸单-（2-乙基己基）酯）。研究了MEHTM（单-（2-乙基己基）偏苯三酸酯）和DEHTM（二-（2-乙基己基）偏苯三酸酯）的异构体作为TOTM的主要代谢产物。

与不带ACC的管组相比，灌注24 h后计算出的DEHP当量（确定的DEHP和MEHP的水平之和）显示出在不具有ACC的管组（A组（201±56.4 µmol / L））中存在较低水平的趋势。 （B组（253±369 µmol / L））。分别在6 h和10 h的灌注时间后，发现A组和B组之间的DEHP当量存在明显差异。对于含TOTM的油管套件，观察到了类似的效果。但是，与DEHP相比，灌注24小时后TOTM的绝对增塑剂迁移速率（TOTM当量）显着低于DEHP（系数超过200）。

结果表明，磷脂涂层（ACC）可以增强增塑剂及其主要降解产物从PVC管到流动血液的迁移。发现TOTM的增强效果稍强，但由于TOTM在所有实验设置中的迁移量均远低于DEHP，因此在医疗器械中，TOTM被证实是DEHP的推荐替代增塑剂。