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A plasmonic sensing platform was developed as a noninvasive method to monitor gas-phase biomarkers related to cystic fibrosis (CF). The nanohole array (NHA) sensing platform is based on localized surface plasmon resonance (LSPR) and offers a rapid data acquisition capability. Among the numerous gas-phase biomarkers that can be used to assess the lung health of CF patients, acetaldehyde was selected for this investigation. Previous research with diverse types of sensing platforms, with materials ranging from metal oxides to 2-D materials, detected gas-phase acetaldehyde with the lowest detection limit at the µmol/mol (parts-per-million (ppm)) level. In contrast, this work presents a plasmonic sensing platform that can approach the nmol/mol (parts-per-billion (ppb)) level, which covers the required concentration range needed to monitor the status of lung infection and find pulmonary exacerbations. During the experimental measurements made by a spectrometer and by a smartphone, the sensing examination was initially performed in a dry air background and then with high relative humidity (RH) as an interferent, which is relevant to exhaled breath. At a room temperature of 23.1 °C, the lowest detection limit for the investigated plasmonic sensing platform under dry air and 72% RH conditions are 250 nmol/mol (ppb) and 1000 nmol/mol (ppb), respectively.

Artificial olfaction is a potential tool for noninvasive chemical monitoring. Application of 'electronic noses' typically involves recognition of 'pretrained' chemicals, while long-term operation and generalization of training to allow chemical classification of 'unknown' analytes remain challenges. The latter analytical capability is critically important, as it is unfeasible to pre-expose the sensor to every analyte it might encounter. Here, we demonstrate a biologically inspired approach where the recognition and generalization problems are decoupled and resolved in a hierarchical fashion. Analyte composition is refined in a progression from general (e.g., target is a hydrocarbon) to precise (e.g., target is ethane), using highly optimized response features for each step. We validate this approach using a MEMS-based chemiresistive microsensor array. We show that this approach, a unique departure from existing methodologies in artificial olfaction, allows the recognition module to better mitigate sensor-aging effects and to better classify unknowns, enhancing the utility of chemical sensors for real-world applications.

A series of C- and Z-shaped complexes of the form cis- and trans-[Re(CO)3(L)2BiBzlm, where L = 4-phenylpyridine, 2,4'-bipyridine, or pyridine and BiBzlm = 2,2'-bisbenzimidizolate, are synthesized. The compounds are acyclic analogues of studied tetraehenium molecular rectangles and are of interest, in part, due to their potential to form ligand-centered mixed-valence compounds upon reduction by one electron.

Effect of lithium intercalation on the transport dynamics and recombination kinetics in dye-sensitized solar cells at lithium densities below 5 atom% is presented. Results show that lithium insertion occurs under the normal operating conditions of a cell containing a lithium electrolyte.

The light harvesting efficiency of dye-sensitized photoelectrodes was enhanced, by coupling a TiO2 photonic crystal layer to a conventional film of TiO2 nanoparticles. The inverse opal photonic crystal caused a significant change in dye absorbance, which depended on the position of the stop band.

Tetrametallic molecular rectangles have been synthesized, based upon rhenium thiolate dimers combined with difunctional pyrazyl and pyridyl ligands. The composition of the proposed structure is supported by H NMR, IR and MS measurements. It is suggested that such molecules may be useful as a basis for further work, such as the creation of larger-cavitied molecular rectangles which could be used for separations and sieving.

The synthesis of a new class of tetracationic rectangular molecules, using transition metal corners, is reported. This new set of tetrametallic hosts were also characterized and their preliminary binding properties investigated. The synthesis proceeded with the creation of a stabilized bimetallic edge via a difunctional chelating bridge and the addition of difunctional pyridyl-based bridges. Both the first and second molecular rectangles bind a representative planar anionic guest molecule, although relatively weakly.