Karabacak Soner, Palaniappan Alagappan, Tony Tsang Siu Hon, Edwin Teo Hang Tong, Gulyás Balázs, Padmanabhan Parasuraman, Yildiz Ümit Hakan
Department of Chemistry, Izmir Institute of Technology, Urla 35430, Izmir, Turkey.
School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Nanomaterials (Basel). 2022 Feb 14;12(4):642. doi: 10.3390/nano12040642.
A rapid and one-pot synthesis of poly 3-thiopheneacetic acid (PTAA) functionalized polyurea polymer dots (Pdots) using polyethyleneimine and isophorone diisocyanate is reported. The one-pot mini-emulsion polymerization technique yielded Pdots with an average diameter of ~20 nm. The size, shape, and concentration of the surface functional groups could be controlled by altering the synthesis parameters such as ultrasonication time, concentration of the surfactant, and crosslinking agent, and the types of isocyanates utilized for the synthesis. Colloidal properties of Pdots were characterized using dynamic light scattering and zeta potential measurements. The spherical geometry of Pdots was confirmed by scanning electron microscopy. The Pdots were post-functionalized by 1,4,7,10 tetraazacyclododecane-1,4,7,10-tetraacetic acid for chelating gadolinium nanoparticles (Gd) that provide magnetic properties to the Pdots. Thus, the synthesized Pdots possess fluorescent and magnetic properties, imparted by PTAA and Gd, respectively. Fluorescence spectroscopy and microscopy revealed that the synthesized dual-functional Gd-Pdots exhibited detectable fluorescent signals even at lower concentrations. Magnetic levitation experiments indicated that the Gd-Pdots could be easily manipulated via an external magnetic field. These findings illustrate that the dua- functional Gd-Pdots could be potentially utilized as fluorescent reporters that can be magnetically manipulated for bioimaging applications.
报道了一种使用聚乙烯亚胺和异佛尔酮二异氰酸酯快速一锅法合成聚3-噻吩乙酸（PTAA）功能化聚脲聚合物点（Pdots）的方法。一锅法微乳液聚合技术得到平均直径约为20 nm的Pdots。通过改变合成参数，如超声处理时间、表面活性剂浓度、交联剂以及用于合成的异氰酸酯类型，可以控制表面官能团的尺寸、形状和浓度。使用动态光散射和zeta电位测量对Pdots的胶体性质进行了表征。通过扫描电子显微镜确认了Pdots的球形几何形状。用1,4,7,10-四氮杂环十二烷-1,4,7,10-四乙酸对Pdots进行后功能化，以螯合钆纳米颗粒（Gd），从而赋予Pdots磁性。因此，合成的Pdots分别具有由PTAA和Gd赋予的荧光和磁性。荧光光谱和显微镜显示，即使在较低浓度下，合成的双功能Gd-Pdots也表现出可检测的荧光信号。磁悬浮实验表明，Gd-Pdots可以通过外部磁场轻松操控。这些发现表明，双功能Gd-Pdots有可能用作荧光报告分子，可通过磁场操控用于生物成像应用。
