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Microarrays require high sensitivity and a broad dynamic range for high-throughput diagnostics and proteomic analysis. We present the fabrication of novel plasmonic protein microarrays using nanostructured ZnO-Nanorods (ZnO-NRs) on 50 nm Au film that exhibits an enhancement of fluorescence up to 200-fold. The as-prepared plasmonic protein microarrays were used for the detection of the carcinoembryonic antigen (CEA) cancer biomarker. The plasmonic enhancement resulted in a detection limit of 27 pg mL −1 in 0.01 M PBS and a dynamic range of 100 pg mL −1 to 100 μg mL −1 . The ZnO-NRs/Au substrates can be mass-manufactured, which is highly promising for the development of low cost, sensitive, and high-throughput protein assay platform for applications in clinical diagnosis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Rational assembly of hierarchical SnO 2 hollow cubes with well-aligned ultrathin primary nanorods. • Well-aligned nanorod-assembled cubic structure maintains highly porous and activated surfaces. • Ultrathin primary nanorods and less-agglomerated configuration promote n-butanol sensing characteristics. Abstract A new type of nonspherical hollow nanocubes functionalized with well-aligned rodlike building blocks have been successfully prepared via a facile one-pot hydrothermal approach in case of SnO 2. The structural and morphological characterization reveals that the dense rodlike SnO 2 subunits are vertically distributed on all of the six equivalent facets of cubic structure. The rodlike primary building blocks with a uniform diameter of about 5 nm exhibit a single-crystalline rutile structure. A two-step sequential growth model is proposed based on observation from a time-dependent evolution process, revealing that the initially formed of well-defined ZnSn(OH) 6 solid cubes can serve as sacrifice self-template for the interior hollowing and vertical growth of SnO 2 nanorods. Moreover, gas sensor based on SnO 2 nanocages exhibits the enhanced sensing performances to n-butanol. The significant decrease in response-recovery time can be attributed not only to the interior cavities combined with permeable shells for fast transfer of gas molecules, but also to these high-activated rodlike subunits with ultrathin diameter. [ABSTRACT FROM AUTHOR]

Pd-loaded SnO 2 hollow microspheres have been successfully prepared via a facile one-pot hydrothermal route and subsequent Pd-loaded treatment without involving any templates, surfactants, or capping agents. The morphological and structural characterization confirms that Pd-loaded SnO 2 hollow microspheres are hierarchically constructed of numerous well-aligned rodlike SnO 2 subunits with ultrathin diameter of about 5–10 nm and monodisperse Pd particles with several nanometers in size. The time-dependent investigation demonstrates that the formation of hierarchical SnO 2 hollow spheres is driven by Ostwald-ripening mechanism. Furthermore, gas sensors based on pure and Pd-loaded SnO 2 have been fabricated. The Pd-loaded SnO 2 hollow microspheres exhibit relatively lower operating temperature, higher response and selectivity to toluene in comparison with that of pure SnO 2 . Besides structural merits of ultrathin nanorod-assembled hollow and porous structure, the promotion of sensing performances can also be attributed to the contribution of catalytic Pd particles. [ABSTRACT FROM AUTHOR]

ZnSnO3 hollow microspheres with a hierarchical structure composed of small nanorods as building blocks are synthesized by a facile one-pot hydrothermal method at 160°C. The individual hierarchical ZnSnO3 microsphere ranges from 600 to 900nm in diameter. The time-dependent hollowing evolution of ZnSnO3 microspheres reveals that the preferential formation of solid ZnSnO3 microspheres and the subsequent dissolution of the interiors to form hollow architectures are performed via Ostwald ripening. Moreover, ZnSnO3 spheres with hollow interiors and permeable surfaces are exploited as gas sensors, exhibiting improved sensing performances to ethanol. The response-recovery times of sensor based on these ZnSnO3 hollow microspheres are 0.9 and 2.2s when the sensor is exposed in ethanol at the optimal operating temperature of 270°C. The significant decrease in response-recovery times are attributed not only to the surface accessibility obtained by the hierarchical hollow architectures, but also to these rodlike building blocks with ultra-thin diameters. [ABSTRACT FROM AUTHOR]