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Chemical sensor arrays provide a simple but powerful means of creating detection specificity through pattern recognition of the responses from an array of highly cross‐reactive sensor elements. Optically responsive nanoparticles have emerged as a useful class of chemical sensors and enabled the development of real‐time, sensitive, cost‐effective and portable microdetectors for targeting biochemical analytes of interest. The unique and fascinating physicochemical properties of nanoparticles play a key role in building promising array‐based sensing platforms. This perspective will describe the principles, fabrication, and applications of various nanoparticle‐based optical sensor arrays. Choice of nanomaterials, optical signal transduction, array substrate and fabrication, as well as statistical data analyses will be elaborately discussed. As two major areas of applications, the detection of environmentally related volatiles and clinical use for biomedical diagnosis will be discussed in detail. Finally, the remaining challenges and future perspectives within this analytical topic will be highlighted. [ABSTRACT FROM AUTHOR]

A low-cost yet highly sensitive colorimetric sensor array for the detection and identification of toxic industrial chemicals (TICs) has been developed. The sensor consists of a disposable array of cross-responsive nanoporous pigments whose colors are changed by diverse chemical interactions with analytes. Clear differentiation among 20 different TICs has been easily achieved at both their IDLH (immediately dangerous to life or health) concentration within 2 min of exposure and PEL (permissible exposure limit) concentration within 5 min of exposure with no errors or misclassifications. Detection limits are generally well below the PEL (in most cases below 5% of PEL) and are typically in the low ppb range. The colorimetric sensor array is not responsive to changes in humidity or temperature over a substantial range. The printed arrays show excellent batch to batch reproducibility and long shelf life (greater than 3 months). 10.1021/ac1020886

The analysis of complex mixtures presents a difficult challenge even for modern analytical techniques, and the ability to discriminate among closely similar such mixtures often remains problematic. Coffee provides a readily available archetype of such highly multicomponent systems. The use of a low-cost, sensitive colorimetric sensor array for the detection and identification of coffee aromas is reported. The color changes of the sensor array were used as a digital representation of the array response and analyzed with standard statistical methods, including principal component analysis (PCA) and hierarchical clustering analysis (HCA). PCA revealed that the sensor array has exceptionally high dimensionality with 18 dimensions required to define 90% of the total variance. In quintuplicate runs of 10 commercial coffees and controls, no confusions or errors in classification by HCA were observed in 55 trials. In addition, the effects of temperature and time in the roasting of green coffee beans were readily observed and distinguishable with a resolution better than 10[degrees]C and 5 min, respectively. Colorimetric sensor arrays demonstrate excellent potential for complex systems analysis in real-world applications and provide a novel method for discrimination among closely similar complex mixtures. 10.1021/ac902823w

A disposable, low-cost colorimetric sensor array has been created by pin-printing onto a hydrophilic membrane 16 chemically responsive nanoporous pigments that are comprised of indicators immobilized in an organically modified silane (ormosil). The array has been used to detect and identify 14 different natural and artificial sweeteners at millimolar concentrations, as well as commonly used individual-serving sweetener packets. The array has shown excellent reproducibility and long shelf life and has been optimized to work in the biological pH regime.

The development of a low-cost, sensitive colorimetric sensor array for the detection and identification of volatile organic compounds (VOCs) is reported. Using an array composed of chemoresponsive dyes, enormous discriminatory power is possible in a simple device that can be imaged easily with an ordinary flatbed scanner. Excellent differentiation of closely related organic compounds can be achieved, and a library of 100 VOCs is presented. The array discriminates among VOCs by probing a wide range of intermolecular interactions, including Lewis acid/base, Bronsted acid/base, metal ion coordination, hydrogen bonding, and dipolar interactions. Importantly, by proper choice of dyes and substrate, the array is essentially nonresponsive to changes in humidity.

An inexpensive high-frequency ultrasound generator is used from a household humidifier to create a useful source for ultrasonic spray pyrolysis and produced submicrometer silica particles that are porous on the nanometer scale. Demonstrations reveal that the use of an inexpensive high frequency ultrasound generator from a household humidifier allows the creation of nanocomposite materials composed of metal nanoparticles and metal oxide matrix.

Author(s): David J. Flannigan [1]; Kenneth S. Suslick (corresponding author) [1] Single-bubble sonoluminescence (SBSL [1, 2, 3, 4, 5]) results from the extreme temperatures and pressures achieved during bubble compression; [...]

Synthetic hosts capable of binding porphyrins is produced by a mixed-covalent-noncovalent molecular imprinting process, where a single binding site is created inside cross-liked dendrimers, which is used for producing synthetic hosts capable of binding porphyrins. The results indicate a high yield of imprinted sites that display high selectivity for binding of porphyrins and are capable of making at least four hydrogen bonds but have only a moderate degree of shape selectivity.

Author(s): Yuri T. Didenko; Kenneth S. Suslick (corresponding author) It is extremely difficult to perform a quantitative analysis of the chemistry [1, 2] associated with multibubble cavitation: unknown parameters include [...]

Author(s): Steven C. Zimmerman (corresponding author) [1, 2]; Michael S. Wendland [1]; Neal A. Rakow [1]; Ilya Zharov [2]; Kenneth S. Suslick [1, 2] Synthetic host systems capable of selectively [...]