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Abstract Spatial structure in biology, spanning molecular, organellular, cellular, tissue, and organismal scales, is encoded through a combination of genetic and epigenetic factors in individual cells. Microscopy remains the most direct approach to exploring the intricate spatial complexity defining biological systems and the structured dynamic responses of these systems to perturbations. Genetic screens with deep single‐cell profiling via image features or gene expression programs have the capacity to show how biological systems work in detail by cataloging many cellular phenotypes with one experimental assay. Microscopy‐based cellular profiling provides information complementary to next‐generation sequencing (NGS) profiling and has only recently become compatible with large‐scale genetic screens. Optical screening now offers the scale needed for systematic characterization and is poised for further scale‐up. We discuss how these methodologies, together with emerging technologies for genetic perturbation and microscopy‐based multiplexed molecular phenotyping, are powering new approaches to reveal genotype–phenotype relationships.

Spatial structure in biology, spanning molecular, organellular, cellular, tissue, and organismal scales, is encoded through a combination of genetic and epigenetic factors in individual cells. Microscopy remains the most direct approach to exploring the intricate spatial complexity defining biological systems and the structured dynamic responses of these systems to perturbations. Genetic screens with deep single‐cell profiling via image features or gene expression programs have the capacity to show how biological systems work in detail by cataloging many cellular phenotypes with one experimental assay. Microscopy‐based cellular profiling provides information complementary to next‐generation sequencing (NGS) profiling and has only recently become compatible with large‐scale genetic screens. Optical screening now offers the scale needed for systematic characterization and is poised for further scale‐up. We discuss how these methodologies, together with emerging technologies for genetic perturbation and microscopy‐based multiplexed molecular phenotyping, are powering new approaches to reveal genotype–phenotype relationships. [ABSTRACT FROM AUTHOR]

Combinatorial optical screening of aprotic electrocatalysts has not yet been achieved primarily due to H+-associated mechanisms of fluorophore modulation. We have overcome this problem by using fluorophore metal-organic complexes. In particular, eosin Y and quinine can be coordinated with various metallic cations (e.g., Li+, Na+, Mg2+, Zn2+, and Al3+) in aprotic solvents, triggering changes in their fluorescent properties. These interactions have been used in a reliable screening method to determine oxygen reduction/evolution reaction activities of 100 Mn-based binary catalysts for the aprotic Li-air battery. [ABSTRACT FROM AUTHOR]

A series of combinatorial optical screening analysis was operated, first for the selection of metal candidates for the ternary Ru-based catalyst and later for the selection of optimized compositions with high performance towards ORR. Among the binary Ru-based catalysts, combinations with Co and Se exhibited the highest performance towards ORR. To investigate a possible synergic effect from the selected metals, the ternary Ru-based combinatorial optical screening was preceded. Among the various combinations and compositions, the optimum composition towards ORR for ternary Ru–Se–Co based catalyst was chosen at 73:12:15 = Ru:Se:Co at. % (named RSC-1). The RSC-1 catalyst measured a current density of −1.28 mAcm −2 at 0.75 V ( vs . RHE), which was about 5 times higher than that of Ru/C (−0.26 mA cm −2 ). The mass activity of RSC-1 (12.20 mA mg −1 ) had an enhanced performance of about 6.8 times than that of Ru/C (1.78 mA mg −1 ) at 0.75 V ( vs . RHE). It was deduced that a synergic effect between the repulsion of oxy-species on the Ru atoms by Se and the alternation of electron configuration by Co, the adequate amounts of Co and Se in the ternary Ru–Se–Co based catalyst could have induced the enhanced ORR performance of the RSC-1 catalyst. [ABSTRACT FROM AUTHOR]

Combinatorial high-throughput optical screening method was developed to find the optimum composition of highly active Pd-based catalysts at the cathode of the hybrid Li-air battery. Pd alone, which is one-third the cost of Pt, has difficulty in replacing Pt; therefore, the integration of other metals was investigated to improve its performance toward oxygen reduction reaction (ORR). Among the binary Pd-based catalysts, the composition of Pd-Ir derived catalysts had higher performance toward ORR compared to other Pd-based binary combinations. The composition at 88:12 at. % (Pd: Ir) showed the highest activity toward ORR at the cathode of the hybrid Li-air battery. The prepared Pd88Ir12/C catalyst showed a current density of -2.58 mA cm-2 at 0.8 V (vs RHE), which was around 30% higher compared to that of Pd/C (-1.97 mA cm-2). When the prepared Pd88Ir12/C catalyst was applied to the hybrid Li-air battery, the polarization of the cell was reduced and the energy efficiency of the cell was about 30% higher than that of the cell with Pd/C. [ABSTRACT FROM AUTHOR]

A combinatorial library having 66 different ternary composi-tions of Pd--Ir--Ce was prepared via the impregnation method to find the optimum ternary composition with the highest performance toward oxygen reduction reaction (ORR) in acid media. Its performance in ORR activity of the combinatorial array was evaluated through two different combinatorial high-throughput screening methods to gain validity: (l) multielectrode half-cell method and (2) optical screening method. From the combinatorial results, the spot at 79:12:9 for Pd--Ir--Ce (at. %) in the array showed the highest ORR activity. The electrochemical characterizations of the single catalyst demonstrates that the optimized Pd79Ir12Ce9/C catalyst shows 1.5 times the ORR activity compared to that of Pd/C catalyst at 0.85 V (vs. RHE). In the Pd--Ir--Ce based catalysts, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results reveal that Ir and Ce are present in the form of Ir02 and CeOy respectively, and the electron configuration of Pd is effectively modified through the decoration with Ir02 and Ce02. From the results, we suggest that the electro-modification of Pd through strong metal--metal oxide interaction with Ir02--Ce02 was a reason for the enhanced ORR activity. [ABSTRACT FROM AUTHOR]

Abstract: We describe here the development of an optical high-throughput screening method for direct methanol fuel cell catalysts based on the fluorescence of protonated quinine generated during electro-oxidation of methanol. The design of the working electrode allows the parallel quantification of the fluorescence development for up to 60 materials. For the preparation of the working electrode a coating routine has been developed, which allows the use of sol–gel derived materials. Due to the required stability of the electrode catalysts towards the acidic polymer membrane, a fast optical pre-screening method for acid stable materials has been developed. The electrochemical high-throughput system has been validated with Pt-Ru catalysts. Automation of data acquisition and data processing led to a fast and reliable high-throughput screening setup. [Copyright &y& Elsevier]