Abstract
Besides the multifunctionality, another equally important aspect of nanoparticles is their engineerability to control the geometrical and chemical properties during fabrication. In this work, we exploited this aspect to define asymmetric surface chemistry of an iron oxide nanosphere by controlling the topology of ligand expression on its surface resulting in a particle with two faces, one displaying only amines and the other only thiols. Specifically, amine-functionalized iron oxide nanospheres were attached on a solid support via a crosslinker containing a disulfide bridge. Liberation of the nanosphere using thiolytic cleavage created thiols on the portion of the particle's surface that interacted with the solid support. Employing a solid-phase strategy and a step-by-step addition of particles, the two unique faces on the same nanosphere served as fittings to assemble them into linear nano-chains. Assembly of chains with various lengths and aspect ratios was controlled by the size and number of the added nanospheres. The characteristics of those chains showed a high degree of uniformity indicating the exceptional control of the synthetic process. Notably, one of the unique properties of the iron oxide nano-chains was an increased magnetic relaxivity, indicating their potential use as contrast agents for magnetic resonance imaging.
Highlights
Nanoparticles [1,2] are excellent delivery vehicles for therapeutic and imaging agents with improved biodistribution and increased delivery efficiency to solid tumors [3,4]
Once the amine-functionalized iron oxide nanospheres were attached to the solid support via DTSSP, the disulfide bond in DTSSP could be cleaved with the addition of a mild reducing agent such as TCEP
The functional group density and swellability of the solid support are important parameters that dictate the number of functional groups available for binding to the nanosphere
Summary
Nanoparticles [1,2] are excellent delivery vehicles for therapeutic and imaging agents with improved biodistribution and increased delivery efficiency to solid tumors [3,4]. Nanomedicine’s greatest advantage over conventional therapies is its ability to combine more than one function by enabling the design of multifunctional nanoparticles that target, image, and destroy tumors [5]. This has led to the development of various nanoparticle delivery systems such as liposomes, dendrimers, other lipidic and polymeric nanoparticles, and metal nanoparticles (e.g. iron oxide and gold) [6]. While the shape of the majority of these particles is spherical due to the methods of preparation, recent advances have fabricated oblate- and rod-shaped nanostructures suitable for biomedical applications such as gold nanorods [7], gold nanochains [8], nanoworms [9,10], and nanonecklaces [11]. A nanonecklace was formed by attaching monofunctionalized gold nanoparticles onto polylysine [11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
