Matière et Systèmes Complexes, UMR 7057 CNRS Université Denis Diderot Paris-VII, Bâtiment Condorcet, 10 rue Alice Domon et Léonie Duquet, 75205 Paris, France.
Matière et Systèmes Complexes, UMR 7057 CNRS Université Denis Diderot Paris-VII, Bâtiment Condorcet, 10 rue Alice Domon et Léonie Duquet, 75205 Paris, France.
Colloids Surf B Biointerfaces. 2019 Jun 1;178:337-345. doi: 10.1016/j.colsurfb.2019.03.020. Epub 2019 Mar 11.
The role of pulmonary surfactant is to reduce the surface tension in the lungs and to facilitate breathing. Surfactant replacement therapy (SRT) aims at bringing a substitute by instillation into the airways, a technique that has proven to be efficient and lifesaving for preterm infants. Adapting this therapy to adults requires to scale the administered dose to the patient body weight and to increase the lipid concentration, whilst maintaining its surface and flow properties similar. Here, we exploit a magnetic wire-based microrheology technique to measure the viscosity of the exogenous pulmonary surfactant Curosurf® in various experimental conditions. The Curosurf® viscosity is found to increase exponentially with lipid concentration following the Krieger-Dougherty law of colloids. The Krieger-Dougherty behavior also predicts a divergence of the viscosity at the liquid-to-gel transition. For Curosurf® the transition concentration is found close to the concentration at which it is formulated (117 g Lversus 80 g L). This outcome suggests that for SRT the surfactant rheological properties need to be monitored and kept within a certain range. The results found here could help in producing suspensions for respiratory distress syndrome adapted to adults. The present work also demonstrates the potential of the magnetic wire microrheology technique as an accurate tool to explore biological soft matter dynamics.
肺表面活性剂的作用是降低肺部的表面张力，促进呼吸。表面活性剂替代疗法（SRT）旨在通过滴注将替代物引入气道，这一技术已被证明对早产儿有效且能救命。将这种疗法应用于成人需要根据患者体重来调整给药剂量，并增加脂质浓度，同时保持其表面和流动特性相似。在这里，我们利用基于磁丝的微流变技术来测量外源性肺表面活性剂 Curosurf®在各种实验条件下的粘度。Curosurf®的粘度随着脂质浓度呈指数增加，符合胶体的 Krieger-Dougherty 定律。Krieger-Dougherty 行为还预测了在液体到凝胶转变时粘度的发散。对于 Curosurf®，转变浓度接近其配方浓度（117 g/L 对 80 g/L）。这一结果表明，对于 SRT，需要监测和保持表面活性剂流变性能在一定范围内。这里的结果可以帮助生产适用于成人的呼吸窘迫综合征混悬剂。本工作还展示了磁丝微流变技术作为探索生物软物质动力学的精确工具的潜力。
