Establishing structure-function relationships in semiconducting polymer-surfactant nanoparticle blends

Semiconducting polymer nanoparticles (SPNs) have been widely investigated for applications in biosensing, biological imaging, cancer therapeutics due to their unique optoelectronic properties. Due to the inherent hydrophobicity of many common SPNs, surfactants are often co-precipitated with polymer to increase colloidal stability, reduce biofouling and add functional elements. While some trends in surfactant choice and preparation methods can be correlated with optical performance and hydrodynamic size of these SPN systems, little is known about the impact these design choices have on structure and morphology. With extensive experience working with nanoparticles for biosensing and imaging applications, the Stevens group aims to establish a structure-function relationship for common SPN-surfactant systems by combining single-particle and bulk analyses. This proposal aims to conduct a full study of surfactant-polymer blends, using the F8BT polymer as a model system and extending the analysis to establish more general trends with two widely used polymers in the photo-therapeutic space (PCPDTBT and DPPT). Furthermore, we hope to investigate structural changes to SPNs that may occur in a protein-rich environment, with an aim to engineer more robust, efficient and stable imaging and therapeutic agents that can perform well in-vivo.

半导体聚合物纳米颗粒（semiconducting polymer nanoparticles，SPNs）凭借其独特的光电特性，已被广泛研究用于生物传感、生物成像及癌症治疗等领域。由于多数常见SPNs具有固有疏水性，通常需将表面活性剂与聚合物共沉淀，以提升胶体稳定性、降低生物污损并引入功能元件。尽管表面活性剂选择与制备方法的部分趋势可与这类SPN体系的光学性能及流体动力学尺寸建立关联，但目前对这些设计选择对其结构与形貌的影响仍知之甚少。斯蒂文斯研究团队（Stevens group）凭借在生物传感与成像用纳米颗粒领域的丰富研究经验，计划结合单颗粒分析与体相分析手段，为常见的SPN-表面活性剂体系建立构效关系。本项目拟对表面活性剂-聚合物共混体系开展全面研究：以F8BT聚合物作为模型体系，并将分析拓展至光治疗领域中两种常用聚合物（PCPDTBT与DPPT），以总结更具普适性的规律。此外，本研究还将探究SPNs在富蛋白环境中可能发生的结构变化，以期开发出在体内可实现优异性能的更稳健、高效且稳定的成像与治疗制剂。