0000000000034686
AUTHOR
Phillip Daniel
showing 5 related works from this author
Fibrous Nanozyme Dressings with Catalase-Like Activity for H2O2 Reduction To Promote Wound Healing
2017
The concentrations of the redox pair hydrogen peroxide (H2O2) and oxygen (O2) can promote or decelerate the progression and duration of the wound healing process. Although H2O2 can reach critically high concentrations and prohibit healing, a sufficient O2 inflow to the wound is commonly desired. Herein, we describe the fabrication and use of a membrane that can contemptuously decrease H2O2 and increase O2 levels. Therefore, hematite nanozyme particles were integrated into electrospun and cross-linked poly(vinyl alcohol) membranes. Within the dual-compound membrane, the polymeric mesh provides a porous scaffold with high water permeability and the nanozymes act as a catalyst with catalase-li…
Amine functionalized ZrO2 nanoparticles as biocompatible and luminescent probes for ligand specific cellular imaging
2015
Surface functionalized ZrO2 nanoparticles show strong photoluminescence and are a versatile tool for cellular targeting due to their chemical functionality. They are highly photostable, biocompatible and amenable to coupling with bioligands (e.g. secondary goat anti-rabbit antibody (GAR) and tri-phenyl phosphine (TPP)) via carbodiimide chemistry. Antibody (GAR) functionalized ZrO2 nanoparticles were used to image the nuclear protein Sirt6, whereas triphenyl phosphonium ion (TPP) functionalized ZrO2 nanoparticles specifically targeted the mitochondria. The versatility and easiness of the ZrO2 surface modification opens up new possibilities for designing non-toxic water dispersible and photos…
Liquid crystalline phases from polymer functionalized ferri-magnetic Fe3O4nanorods
2017
Here, we present the surface functionalization of anisotropic in form ferri-magnetic Fe3O4-nanorods (NRs) with a diblock copolymer, having a PMMA- or PDEGMEMA-block, for solubilization, and a dopamine anchor block. These polymers were synthesized through RAFT polymerization via a macro-initiator approach. The successful surface functionalization, performed via a grafting-to method, was monitored using TGA, IR and TEM measurements. The NRs were very soluble in organic solvents after functionalization. Afterwards, the liquid crystalline (LC) behavior was investigated. During solvent evaporation, birefringent domains were formed. The self-assembly into lyotropic LC structures could be observed…
The surface chemistry of iron oxide nanocrystals: surface reduction of γ-Fe2O3 to Fe3O4 by redox-active catechol surface ligands
2018
The effect of surface functionalization on the structural and magnetic properties of catechol-functionalized iron oxide magnetic (γ-Fe2O3) nanocrystals was investigated. γ-Fe2O3 nanocrystals (NCs) were synthesized from iron acetyl acetonate in phenyl ether with 1,2-tetradecanediol, oleic acid, and oleylamine. X-ray powder diffraction in combination with Mossbauer spectroscopy revealed the presence of γ-Fe2O3 (maghemite) particles only. Replacement of oleic acid (OA) with catechol-type 3,4-dihydroxyhydrocinnamic acid (DHCA) or polydentate polydopamine acrylate (PDAm) surface ligands leads to a pronounced change of the magnetic behavior of the γ-Fe2O3 nanocrystals and separated them into two …
Ultrastrong composites from dopamine modified-polymer-infiltrated colloidal crystals
2015
Although strong and stiff synthetic composites have long been developed, the microstructure of today's most advanced composites has yet to achieve the sophisticated hierarchy of hybrid materials built up by living organisms. We have assembled hard and tough multilayered nanocomposites, which contain alternating layers of Fe3O4 nanoparticles and a 3-hydroxy-tyramine (dopamine) substituted polymer (dopamine modified polymer), strongly cemented together by chelation through infiltration of the polymer into the Fe3O4 mesocrystal. With a Young's modulus of 17 ± 3 GPa and a hardness of 1.3 ± 0.4 GPa the nanocomposite exhibits high resistance against elastic as well as plastic deformation. Key fea…