Decoding the conductance of disordered nanostructures: a quantum inverse problem

Obtaining conductance spectra for a concentration of disordered impurities distributed over a nanoscale device with sensing capabilities is a well-defined problem. However, to do this inversely, i.e., extracting information about the scatters from the conductance spectrum alone, is not an easy task. In the presence of impurities, even advanced techniques of inversion can become particularly challenging. This article extends the applicability of a methodology we proposed capable of extracting composition information about a nanoscale sensing device using the conductance spectrum. The inversion tool decodes the conductance spectrum to yield the concentration and nature of the disorders responsible for conductance fluctuations in the spectra. We present the method for simple one-dimensional systems like an electron gas with randomly distributed delta functions and a linear chain of atoms. We prove the generality and robustness of the method using materials with complex electronic structures like hexagonal boron nitride, graphene nanoribbons, and carbon nanotubes. We also go on to probe distribution of disorders on the sublattice structure of the materials using the proposed inversion tool.

A tetrahedral DNA nanorobot with conformational change in response to molecular trigger

Dynamic DNA origami nanostructures that respond to external stimuli are promising platforms for cargo delivery and nanoscale sensing. However, the low stability of such nanostructures under physiological conditions presents a...

Fluorescent Nanodiamond–Nanogels for Nanoscale Sensing and Photodynamic Applications

Fluorescent nanodiamonds (NDs) are carbon-based nanoparticles with various outstanding magneto-optical properties. After preparation, NDs have a variety of different surface groups that determine their physicochemical properties. For biological applications, surface modifications are crucial to impart a new interphase for controlled interactions with biomolecules or cells. Herein, a straight-forward synthesis concept denoted "adsorption-crosslinking" is applied for the efficient modification of NDs, which sequentially combines fast non-covalent adsorption based on electrostatic interactions and subsequent covalent cross-linking. As a result, a very thin and uniform nanogel coating surrounding the NDs is obtained, which imparts reactive groups as well as high colloidal stability. The impact of the reaction time, monomer concentration, molecular weight, and structure of the cross-linker on the resulting nanogel shell, the availability of reactive chemical surface functions and the quantum sensing properties of the coated NDs has been assessed and optimized. Post-modification of the nanogel-coated NDs was achieved with phototoxic ruthenium complexes yielding ND-based probes suitable for photodynamic applications. The adsorption-crosslinking ND functionalization reported herein provides new avenues towards functional probes and traceable nanocarriers for high resolution bioimaging, nanoscale sensing and photodynamic applications. <br>

Fluorescent Nanodiamond–Nanogels for Nanoscale Sensing and Photodynamic Applications

Fluorescent nanodiamonds (NDs) are carbon-based nanoparticles with various outstanding magneto-optical properties. After preparation, NDs have a variety of different surface groups that determine their physicochemical properties. For biological applications, surface modifications are crucial to impart a new interphase for controlled interactions with biomolecules or cells. Herein, a straight-forward synthesis concept denoted "adsorption-crosslinking" is applied for the efficient modification of NDs, which sequentially combines fast non-covalent adsorption based on electrostatic interactions and subsequent covalent cross-linking. As a result, a very thin and uniform nanogel coating surrounding the NDs is obtained, which imparts reactive groups as well as high colloidal stability. The impact of the reaction time, monomer concentration, molecular weight, and structure of the cross-linker on the resulting nanogel shell, the availability of reactive chemical surface functions and the quantum sensing properties of the coated NDs has been assessed and optimized. Post-modification of the nanogel-coated NDs was achieved with phototoxic ruthenium complexes yielding ND-based probes suitable for photodynamic applications. The adsorption-crosslinking ND functionalization reported herein provides new avenues towards functional probes and traceable nanocarriers for high resolution bioimaging, nanoscale sensing and photodynamic applications. <br>

Fluorescent Nanodiamond–Nanogels for Nanoscale Sensing and Photodynamic Applications

Fluorescent nanodiamonds (NDs) are carbon-based nanoparticles with various outstanding magneto-optical properties. After preparation, NDs have a variety of different surface groups that determine their physicochemical properties. For biological applications, surface modifications are crucial to impart a new interphase for controlled interactions with biomolecules or cells. Herein, a straight-forward synthesis concept denoted "adsorption-crosslinking" is applied for the efficient modification of NDs, which sequentially combines fast non-covalent adsorption based on electrostatic interactions and subsequent covalent cross-linking. As a result, a very thin and uniform nanogel coating surrounding the NDs is obtained, which imparts reactive groups as well as high colloidal stability. The impact of the reaction time, monomer concentration, molecular weight, and structure of the cross-linker on the resulting nanogel shell, the availability of reactive chemical surface functions and the quantum sensing properties of the coated NDs has been assessed and optimized. Post-modification of the nanogel-coated NDs was achieved with phototoxic ruthenium complexes yielding ND-based probes suitable for photodynamic applications. The adsorption-crosslinking ND functionalization reported herein provides new avenues towards functional probes and traceable nanocarriers for high resolution bioimaging, nanoscale sensing and photodynamic applications. <br>