Sub-100 nm gold nanomatryoshkas improve photo-thermal therapy efficacy in large and highly aggressive triple negative breast tumors

There is an unmet need for efficient near-infrared photothermal transducers for the treatment of highly aggressive cancers and large tumors where the penetration of light can be substantially reduced, and the intra-tumoral nanoparticle transport is restricted due to the presence of hypoxic or necrotic regions. We report the performance advantages obtained by sub 100 nm gold nanomatryushkas, comprising concentric gold–silica–gold layers compared to conventional ~ 150 nm silica core gold nanoshells for photothermal therapy of triple negative breast cancer. We demonstrate that a 33% reduction in silica–core–gold-shell nanoparticle size, while retaining near-infrared plasmon resonance, and keeping the nanoparticle surface charge constant, results in a four to five fold tumor accumulation of nanoparticles following equal dose of injected gold for both sizes. The survival time of mice bearing large (> 1000 mm3) and highly aggressive triple negative breast tumors is doubled for the nanomatryushka treatment group under identical photo-thermal therapy conditions. The higher absorption cross-section of a nanomatryoshka results in a higher efficiency of photonic to thermal energy conversion and coupled with 4–5 × accumulation within large tumors results in superior therapy efficacy

Raman Spectroscopy as a Probe of Surface Defects in Nb for SRF Cavities

Superconducting RF (SRF) cavities made of Nb are an enabling device for future linear accelerators. Recently it has been demonstrated that hot spots in SRF cavities, which diminish performance, are correlated with a high density of defects (etch pits) especially near grain boundaries. For a pit to cause local heating, it is likely that near-surface impurities, e.g. hydrides or oxides are leading to suppressed superconductivity. New probes are needed to measure such complexes. Here we present Raman spectroscopy. Raman is a fast, nonperturbative method that can measure the vibrational modes of Nb-O and Nb-H complexes by inelastic light scattering. These can then be compared to molecular dynamics simulations to identify oxide and hydride phases. The probing depth of Raman is estimated from the skin depth of the 785 nm laser in the bulk Nb ~ 10-20 nm. This is a reasonable fraction of the superconducting penetration depth ~ 45 nm. Simulating manufacturing processes of SRF cavities may shed light on the origins and composition of hot spots, and their relationship with defects in the material. Defects such as pits, whose origins are yet unknown, are found in the hot spots of completed cavities. Raman spectroscopy is used here to identify changes in the surface chemistry after manipulations such as creating artificial pits, exposing the material to chemical etching, or cold-working the material. BCP exposure and cold-working are common to the SRF manufacturing process

All optical nanoscale sensor

A composition comprising a nanoparticle and at least one adsorbate associated with the nanoparticle, wherein the adsorbate displays at least one chemically responsive optical property. A method comprising associating an adsorbate with a nanoparticle, wherein the nanoparticle comprises a shell surrounding a core material with a lower conductivity than the shell material and the adsorbate displays at least one chemically responsive optical property, and engineering the nanoparticle to enhance the optical property of the adsorbate. A method comprising determining an optical response of an adsorbate associated with a nanoparticle as a function of a chemical parameter, and parameterizing the optical response to produce a one-dimensional representation of at least a portion of a spectral window of the optical response in a high dimensional vector space

Au Nanomatryoshkas as Efficient Near-Infrared Photothermal Transducers for Cancer Treatment: Benchmarking against Nanoshells

Au nanoparticles with plasmon resonances in the near-infrared (NIR) region of the spectrum efficiently convert light into heat, a property useful for the photothermal ablation of cancerous tumors subsequent to nanoparticle uptake at the tumor site. A critical aspect of this process is nanoparticle size, which influences both tumor uptake and photothermal efficiency. Here, we report a direct comparative study of ∼90 nm diameter Au nanomatryoshkas (Au/SiO2/Au) and ∼150 nm diameter Au nanoshells for photothermal therapeutic efficacy in highly aggressive triple negative breast cancer (TNBC) tumors in mice. Au nanomatryoshkas are strong light absorbers with 77% absorption efficiency, while the nanoshells are weaker absorbers with only 15% absorption efficiency. After an intravenous injection of Au nanomatryoshkas followed by a single NIR laser dose of 2 W/cm2 for 5 min, 83% of the TNBC tumor-bearing mice appeared healthy and tumor free >60 days later, while only 33% of mice treated with nanoshells survived the same period. The smaller size and larger absorption cross section of Au nanomatryoshkas combine to make this nanoparticle more effective than Au nanoshells for photothermal cancer therapy

Combining Solar Steam Processing and Solar Distillation for Fully Off-Grid Production of Cellulosic Bioethanol

Conventional bioethanol for transportation fuel typically consumes agricultural feedstocks also suitable for human consumption and requires large amounts of energy for conversion of feedstock to fuel. Alternative feedstocks, optimally those not also in demand for human consumption, and off-grid energy sources for processing would both contribute to making bioethanol far more sustainable than current practices. Cellulosic bioethanol production involves three steps: the extraction of sugars from cellulosic feedstock, the fermentation of sugars to produce ethanol, and the purification of ethanol through distillation. Traditional production methods for extraction and distillation are energy intensive and therefore costly, limiting the advancement of this approach. Here we report an initial demonstration of the conversion of cellulosic feedstock into ethanol by completely off-grid solar processing steps. Our approach is based on nanoparticle-enabled solar steam generation, in which high-efficiency steam can be produced by illuminating light-absorbing nanoparticles dispersed in H₂O with sunlight. We used solar-generated steam to successfully hydrolyze feedstock into sugars; we then used solar steam-distillation to purify ethanol in the final processing step. Coastal hay, a grass grown for livestock feed across the southern United States, and sugar cane as a control are successfully converted to ethanol in this proof-of-concept study. This entirely off-grid solar production method has the potential to realize the long-dreamed-of goal of sustainable cellulosic bioethanol production

Post-combustion Capture of CO2: Results from the Solvent Absorption Capture Plant at Hazelwood Power Station Using Potassium Carbonate Solvent

Post-combustion capture of CO2 from flue gas generated in a 1600 MW brown-coal-fired power station has been demonstrated using a solvent absorption process. The plant, located at International Power’s Hazelwood power station in Victoria’s Latrobe Valley, was designed to capture up to 25 tons/day of CO2 (expandable to 50 tons/day of CO2). The design of the capture plant was based on a proprietary solvent (BASF PuraTreat F). The main focus of this work, however, is to describe the performance of the plant using an unpromoted 30 wt % potassium carbonate (K2CO3) solution. The CO2-capture plant was successfully operated using both BASF PuratTreat F and K2CO3, during which performance data were collected and analyzed. Although the plant only absorbed 20–25% of CO2 from the flue gas when using the potassium carbonate solvent, valuable operating data were collected, which enabled process simulations to be compared to real plant data. Aspen Plus software was used to predict the performance of the plant while operating with potassium carbonate. In general, the model shows a slight difference (within ±5%) compared to the pilot-plant results. This benchmarked model is an important part of the ongoing development of novel precipitating potassium carbonate processes for large-scale post-combustion CO2 capture

Demonstration of a Concentrated Potassium Carbonate Process for CO2 Capture

A precipitating potassium carbonate (K2CO3)-based solvent absorption process has been developed by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) for capturing carbon dioxide (CO2) from industrial sources, such as power plant flue gases. Demonstration of this process is underway using both a laboratory-based pilot plantlocated at The University of Melbourne and an industrial pilot plant located at the Hazelwood Power Station in Victoria, Australia. The laboratory-scale pilot plant has been designed to capture 4-10 kg/h CO2 from an air/CO2 feed gas rate of 30-55 kg/h. The power-station-based pilot plant has been designed to capture up to 1 tonne/day CO2 from the flue gas of a browncoal-fired power station. In this paper, results from trials using concentrated potassium carbonate (20-40 wt %) solvent are presented for both pilot plants. Performance data (including pressure drop, holdup, solvent loadings, temperature profile, and CO2 removal efficiency) have been collected from each plant and presented for a range of operating conditions. Plant data for thelaboratory-scale pilot plant (including temperature profiles, solvent loadings, and exit gas CO2 concentrations) have been used to validate and further develop Aspen Plus simulations, in anticipation of further work involving precipitation and the industry based pilot plant