Impact of Particle Size on the Nonlinear Magnetic Response of Iron Oxide Nanoparticles during Frequency Mixing Magnetic Detection.

Magnetic nanoparticles (MNPs), particularly iron oxide nanoparticles (IONPs), play a pivotal role in biomedical applications ranging from magnetic resonance imaging (MRI) enhancement and cancer hyperthermia treatments to biosensing. This study focuses on the synthesis, characterization, and application of IONPs with two different size distributions for frequency mixing magnetic detection (FMMD), a technique that leverages the nonlinear magnetization properties of MNPs for sensitive biosensing. IONPs are synthesized through thermal decomposition and subsequent growth steps.

Impact of device design on the electronic and optoelectronic properties of integrated Ru-terpyridine complexes.

The performance of nanoelectronic and molecular electronic devices relies strongly on the employed functional units and their addressability, which is often a matter of appropriate interfaces and device design. Here, we compare two promising designs to build solid-state electronic devices utilizing the same functional unit. Optically addressable Ru-terpyridine complexes were incorporated in supramolecular wires or employed as ligands of gold nanoparticles and contacted by nanoelectrodes.

Single Interdigital Transducer Approach for Gravimetrical SAW Sensor Applications in Liquid Environments.

Surface acoustic wave (SAW) devices are well known for mass-sensitive sensor applications. In biosensing applications, chemical and biochemically evoked binding processes on surfaces are detected in liquid environments using delay line or resonator sensor configurations, preferably in combination with the appropriate microfluidic devices. All configurations share the common feature of analyzing the transmission characteristic of the propagating SAW.

Directed Self-Assembly and Infrared Reflection Absorption Spectroscopy Analysis of Amphiphilic and Zwitterionic Janus Gold Nanoparticles.

Here, we report an approach to use infrared reflection absorption spectroscopy (IRRAS) for the unambiguous proof of the presence as well as the spatial distribution of organic ligands on the Janus gold nanoparticle (AuNP) surface. For this purpose we synthesized amphiphilic and zwitterionic Janus AuNPs and immobilized these on pretreated gold surfaces by directed self-assembly, exploiting hydrophilic/hydrophobic or electrostatic interactions, respectively. Thus, we obtained macroscopic two-dimensional arrays of Janus AuNPs exhibiting a specific orientation.

Differential adsorption of gold nanoparticles to gold/palladium and platinum surfaces.

Integration of molecule-capped gold nanoparticles (AuNP) into nanoelectronic devices requires detailed knowledge about the AuNP-electrode interface. Here, we report the pH-dependent adsorption of amine or carboxylic acid-terminated gold nanoparticles on platinum or gold/palladium (30% Pd) alloy, respectively. We synthesized amine-terminated AuNP, applying a new solid phase supported approach, as well as AuNP exhibiting carboxylic acid as terminal groups.