Magnetically Responsive Carboxylated Magnetite-Polydipyrrole/Polydicarbazole Nanocomposites of Core−Shell Morphology. Preparation, Characterization, and Use in DNA Hybridization

Abstract

Novel bis-heterocyclic mono- and dicarboxylated dipyrrole and dicarbazole monomers have been synthesized in a modular manner. Their oxidative polymerization around magnetite nanosized particles has been investigated and optimized toward new magnetic magnetite-polydipyrrole/polydicarbazole nanocomposites (NCs) of a core-shell morphology. These NCs were thoroughly characterized by FT-IR, TGA (Thermal Gravimetric Analysis), low- and high-resolution TEM/HR-TEM microscopies, and Mössbauer spectroscopy along with magnetization studies. Exploiting the versatile COOH chemistry (activation by water-soluble diimides) introduced by the polymeric shell, DNA hybridization experiments have been conducted onto NC surfaces using an efficient blue-colored HRP-based enzymatic screening biological system. Highly parallel NC-supported DNA hybridization experimentations revealed that these NCs presented an interesting potential for DNA-based diagnostic applications.

Electrical impedance spectroscopy investigation of surfactant–magnetite–polypyrrole particles

“…Similar techniques can be applied to prepare hybrid (conducting polymer)/(iron oxide) particles that, among other desired properties, possess promising EMI characteristics [11,18] and can be used for electrochemical storage [19] or DNA hybridization [20]. Because of its environmental stability, PPY has been one the conducting polymers most used for obtaining such binary composites through different preparation methods such as the sol-gel [20,21] and emulsion polymerization [19] techniques, and chemical polymerization on colloidal silica-coated magnetite particles [22]. Also, PPY-coated Fe 3 O 4 fillers have been added to epoxy blends as a means of conferring the right amount of electrical conductivity to the composite material [23].…”

A facile strategy for covalent binding of nanoparticles onto carbon nanotubes

“…Functionalization of the water-soluble MNP surface allows the formation of MNP bioconjugates that can bind specifically to target molecules and form stable conjugate complexes. As such, MNPs have already been used successfully in cellular imaging [29], immunoassays [30], DNA hybridization [31], and barcoding [32]. Our results have direct implications for self-assembly of carbon nanotube nanodevices using chemical attachment strategies.…”

Magnetic colloid by PLA: Optical, magnetic and thermal transport properties

“…Ferrofluids or magnetic nanofluids are the colloidal suspensions related to the surface modified magnetic nanoparticles (2-20 nm) dispersed in the base fluid. Ferrofluids have numerous applications in biomedical categories: the cancer treatment by hyperthermia [5], MRI contrast agent [6], drug delivery [7], DNA hybridization [8] and cell separation [9]. The thermal transport properties of colloidal magnetic ferrofluids nanoparticles were reported previously [10].…”