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We report on a simple, rapid, and room-temperature undergraduate-level experiment for gold nanoparticle synthesis, analysis, and utilization as a catalyst for the sodium-borohydride-assisted reduction of methylene blue and Congo red dyes. Typical procedures toward gold nanoparticle formation require an elaborate, lengthy synthesis (some requiring 1 h for completion of nanoparticle formation and ripening), whereas faster methods frequently yield inhomogeneous or catalytically inferior gold nanoparticles. This situation limits the usefulness of gold nanoparticles as rudimentary nanochemistry teaching tools in time-restricted undergraduate laboratories. The rapid gold nanoparticle synthesis presented herein utilizes ascorbic acid or sodium borohydride as dual reducing/capping agents to produce catalytically active gold nanoparticles at the "speed of mixing" under ambient conditions, allowing preparation and characterization to be performed within a single laboratory period. Furthermore, whereas most gold nanoparticle syntheses require rigorously cleaned glassware to avoid contamination and irreproducibility, the devised undergraduate experiment reported here alleviates this burden by employing disposable reaction vessels. Thus, this undergraduate-level laboratory experiment is designed to provide a meaningful introduction to metal nanoparticle synthesis and application while simultaneously being accommodated by a typical 2-4 h laboratory period, providing much-needed teaching assistance in the growing field of nanomaterials education.

A simple, low‐cost and portable sensor for colorimetric determination of As(III) was developed. The sensing is carried out using a microcentrifuge tube as a mini‐reactor, where an Fe(III)‐1,10‐phenanthroline doped polyvinyl alcohol thin film is cast on the underside of the cap. Once Fe(III)‐1,10‐phenanthroline is reduced by arsine gas generated in situ from As(III), yielding the Fe(II)‐1,10‐phenanthroline complex, the red coloured product can be detected using colour analysis software. The As(III) content is then determined based upon the colour intensity of Fe(II)‐1,10‐phenanthroline on the film. Experimental conditions were optimised, and parameters affecting the complex formation and arsenic speciation were investigated. The method developed proved to be a selective colorimetric sensor for As(III). More significantly, the device could be directly used to detect As(III) in the field without any sample preparation requirements. The recovery for industrial wastewater and groundwater was found to be 97.5%‐104.0%. Hence, the thin film‐based test kit is easy to operate, portable and practical for the measurement of As(III) in the field. [ABSTRACT FROM AUTHOR]

Ensuring the integrity of quality control and assurance of consumable products across consumer goods distribution and supply chains is pertinent to ensure consumer products of high quality to guarantee public health. Several analytical strategies, and technological innovations have been developed over the years for the quality control and assurance of consumable products. However, the simplicity and the noninvasive and nondestructive properties of Raman, near-infrared (NIR), and Fourier-transform infrared (FTIR) spectrometers, coupled with the low-cost and portability make these instrumental techniques excellent tools of choice for quality control and assurance of consumable products. This review article examines recent technological innovations and advances in Raman, NIR and FTIR spectroscopic instrument development and multivariate analyses used in consumer product analysis. New innovations in Raman, NIR, and FTIR spectroscopies as applied to analytical method development for purity analysis, quality control and assurance of consumable food products between January 2015 and December 2018 are discussed. Applications of data processing strategies and multivariate analyses of spectral data for instrumental and sample calibration, chemical analysis, and pattern recognition of consumable products are presented. The review also provides insight into the future trajectory of innovative technological developments in molecular spectroscopy, and multivariate analyses pertaining to general applications for consumer product analysis. [ABSTRACT FROM AUTHOR]

Ensuring the integrity of quality control and assurance of consumable products across consumer goods distribution and supply chains is pertinent to ensure consumer products of high quality to guarantee public health. Several analytical strategies, and technological innovations have been developed over the years for the quality control and assurance of consumable products. However, the simplicity and the noninvasive and nondestructive properties of Raman, near-infrared (NIR), and Fourier-transform infrared (FTIR) spectrometers, coupled with the low-cost and portability make these instrumental techniques excellent tools of choice for quality control and assurance of consumable products. This review article examines recent technological innovations and advances in Raman, NIR and FTIR spectroscopic instrument development and multivariate analyses used in consumer product analysis. New innovations in Raman, NIR, and FTIR spectroscopies as applied to analytical method development for purity analysis, quality control and assurance of consumable food products between January 2015 and December 2018 are discussed. Applications of data processing strategies and multivariate analyses of spectral data for instrumental and sample calibration, chemical analysis, and pattern recognition of consumable products are presented. The review also provides insight into the future trajectory of innovative technological developments in molecular spectroscopy, and multivariate analyses pertaining to general applications for consumer product analysis. [ABSTRACT FROM AUTHOR]

To develop ionic liquid/porous silicon (IL/pSi) microarrays we have contact pin-printed 20 hydrophobic and hydrophilic ionic liquids onto as-prepared, hydrogen-passivated porous silicon (ap-pSi) and then determined the individual IL spot size, shape and associated pSi surface chemistry. The results reveal that the hydrophobic ionic liquids oxidize the ap-pSi slightly. In contrast, the hydrophilic ionic liquids lead to heavily oxidized pSi (i.e., ox-pSi). The strong oxidation arises from residual water within the hydrophilic ILs that is delivered from these ILs into the ap-pSi matrix causing oxidation. This phenomenon is less of an issue in the hydrophobic ILs because their water solubility is substantially lower., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)