In situ synthesis of Fe3O4@SiO2 core–shell nanoparticles via surface treatment

Polymeric Membrane Marine Sensors with a Regenerable Antibiofouling Coating Based on Surface Modification of a Dual-Functionalized Magnetic Composite

“…Moreover, the successful modifications with PDA-PSBMA and QAC C18 can also be confirmed by the remarkable changes in the surface zeta potential of the Fe 3 O 4 particles (Figure C). Since the surfaces of Fe 3 O 4 particles can be hydroxylated in DI water by forming a large number of Fe–OH groups, the positive or negative charges could be formed on the particle surfaces through the amphoteric dissociation of these hydroxide groups with an isoelectric point of ∼7.0, , which means that the surfaces of Fe 3 O 4 particles are positively charged in DI water (pH 6.1). The shift of the zeta potential to a negative value after the modification of the PDA-PSBMA layer can be ascribed to the phenolic hydroxyl groups of PDA, which could be deprotonated in DI water with the formation of negative charges .…”

Preparation of Dual-Layered Core–Shell Fe3O4@SiO2 Nanoparticles and Their Properties of Plasmid DNA Purification

“…In the case of the dense Fe 3 O 4 @SiO 2 complex, an intense peak around 1250-950 cm −1 and a broad peak at 3700-3000 cm −1 were observed in the FT-IR spectrum, which corresponded to the Si-O-Si bonds and O-H stretching bonds [6,13,25]. In the spectra of the porous and dual Fe 3 O 4 @SiO 2 , the Si-O-Si bond peak was maintained, but two peaks at wavelength ranges of 3000-2840 cm −1 (attributed to the C-H stretching bond) and 1700-1500 cm −1 replaced the corresponding peak of the O-H stretching bond [12,13]. The formation of these new bonds indicates that the CTAB affected the coating layer or remained intact after coating.…”

“…Since the core-shell structure could take advantage of both an Fe 3 O 4 core, which could control nanoparticles through its superparamagnetic properties, and an SiO 2 shell, which can be used for purifying biomaterials such as nucleic acid and antibodies, surface functionalization through silane grafting, and enhancing chemical and thermal stabilities, core-shell-structured Fe 3 O 4 @SiO 2 nanoparticles have received extensive attention, and a large number of studies have been conducted on the fabrication method and application of Fe 3 O 4 @SiO 2 nanoparticles [12][13][14][15][16]. Most fabrication studies of Fe 3 O 4 @SiO 2 nanoparticles have been conducted using the sol-gel method with silane precursors such as tetraethyl orthosilicate (TEOS) [6,13] and tetramethyl orthosilicate (TMOS) [2,3]. It has been reported that biomaterials, such as plasmid DNA, RNA, and antibodies, have been successfully purified using Fe 3 O 4 @SiO 2 nanoparticles in high-speed separation processes [17,18].…”

Polisakaridoetan oinarritutako hidrogelak eta haien aplikazioak biomedikuntzan

“…Kitinaren deribatu garrantzitsuenetarikoa kitosanoa da, eta kitinaren desazetilazio alkalino partzialaren bitartez lortu ohi da. Oinarrizko egoeran kitosanoa uretan disolbatzen ez den arren, pH azidoetan disolbatu daiteke, amino taldeak ionizatu egiten direlako chit-NH 3 + konposatua osatuz eta solubilitatea areagotuz [61]. Kitosanoak hidrogela osatzeko duen gaitasuna hidrogeno zubiak sortzeko ahalmenaren ondorioz gauzatzen da, pH-arekiko mendekotasun zuzena izanik [8].…”

“…Hidrogelaren porositate eta ur kantitatea, prestakuntza prozesuaren menpe egoteaz gain, inguruneko estimuluen menpe daude (pH, tenperatura…); estimulu horiekiko sentikorrak diren materialak lortuz. Besteak beste, zelulosa/Fe 2 O 3 nahastean oinarritutako hidrogelak garatu dira, eremu magnetikoen bitartez proteinen askapen kontrolatua bideratzen dutenak [32].…”