Flow hydrodynamics-dependent assembly of polymer-tethered gold nanoparticles in microfluidic channels. (16th September 2020)

• Record Type: Journal Article
• Authors: Mao, Xi; Tan, Zhengping; Lan, Wei; Wang, Huayang; Tan, Haiying; Li, Fan; Wang, Ke; Wu, Ming; Luo, Xiaobing; Zhang, Lianbin; Xu, Jiangping; Zhu, Jintao
• Is Part Of: Materials chemistry frontiers. Volume 4:Number 11(2020)
• Page Start: 3240
• Page End: 3250
• Publication Date: 2020-09-16
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/d0qm00456a
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : Recently, self-assembly of polymer-tethered inorganic nanoparticles (NPs) in microfluidic chips has been employed as an effective approach to fabricate novel assemblies. Abstract : Recently, self-assembly of polymer-tethered inorganic nanoparticles (NPs) in microfluidic chips has been employed as an effective approach to fabricate novel assemblies. Herein, we systematically studied the self-assembly of polystyrene-grafted gold NPs (AuNP@PS) in microfluidic chips into various structures by changing the organic/aqueous flow rate ratio ( R Q ), the total flow rate ( Q tot ), the molecular weight of PS ligands ( M n ), and the radius of the AuNP core ( r 0 ). Morphological transitions of the assemblies were demostrated to be dependent on the hydrodynamic conditions, i.e., R Q and Q tot . We then employed the effective softness ( λ eff ) to describe the structural features of AuNP@PS and the formation of assemblies. The results indicated that the morphology of the AuNP@PS assemblies was affected by λ eff . When λ eff ≤ 2.96, lamellar structures ( e.g., nanosheets and bowl-like assemblies) were captured by varying R Q and Q tot . When λ eff > 2.96, only spherical assemblies were obtained with the increase of R Q and Q tot . We further found that the AuNP@PS assemblies showed an excellent photothermal conversion performance. These findings not only demonstrate the kinetics dependent assembly behavior of polymer-tethered NPs in microfluidic chips, but also provide a convenient way to prepare NP assemblies with well-ordered structures, potentially useful in drug delivery, photothermal therapy, and others.