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This mini review chronicles the role of Ru(edta) (edta4− = ethylenediaminetetraacetate) towards catalysing the electrochemical transformation of nitrogen cycle reactions, elucidating the complex mechanistic schemes.

Abstract: Photocatalytic transformation of small substrate molecules to useful products through an environmentally benign and economically viable pathway is a challenging area of research of continual importance. This review focuses on our perception of the application of ruthenium(III) complexes comprising ‘edta’ ligand (edta4- = ethylenediaminetetraacetate) as a ‘redox mediator’ or ‘relay’ in photocatalytic electron transfer reaction pertaining to the conversion of small substrate molecules viz. hydrazine to ammonia, bicarbonate to formate, dioxygen to hydrogen peroxide. In this article, the prospect of [RuIII(edta)(H2O)]- and [RuIII(edta)(pz)]- to act as ‘redox mediator’ or ‘molecular catalysts’ in photocatalytic transformations of aforesaid small molecules are assessed systematically.

Learning outcomes The learning outcomes are as follows: Understand the concept and characteristics of Bottom of Pyramid (BoP) markets; understand the concept and characteristics of frugal innovations; understand the Design Thinking approach to product design and how it might be useful to develop frugal innovations for BoP markets. Case overview/Synopsis The case details the journey of a group of students at a premier engineering college in India. The group aimed to develop and implement a social innovation that addressed a serious and important health issue – menstrual hygiene practices among urban slum dwellers in India. The case begins with how a chance visit to an NGO inspired a pair of students to take up this issue, how the project unfolded at their college, the challenges faced in their journey and, finally, an outcome that was only a partial success. It raises important questions of challenges that are specific to bottom of pyramid markets in emerging economies. The case can provide a context for discussions on approaching frugal innovations from a Design Thinking perspective. Complexity academic level This case can be used in social innovation courses/modules at an undergraduate or graduate level in social innovation and social entrepreneurship courses. The case is best positioned towards the beginning of the course as an overview of the process of Social Innovation, and to discuss the relevance of concepts of BoP markets and frugal innovation. Supplementary materials Teaching Notes are available for educators only. Subject code CSS 7: Management Science.

The reduction of molecular oxygen (O2) and hydrogen peroxide (H2O2) by [RuII(edta)(pz)]2− (edta4− = ethylenediaminetetraacetate; pz = pyrazine) has been studied spectrophotometrically and kinetically in aqueous solution. Exposure of the aqua-analogue [RuII(edta)(H2O)]2− to O2 and H2O2 resulted in the formation of [RuIII(edta)(H2O)]− species, with subsequent formation of the corresponding RuVO complex. A working mechanism for the O2 and H2O2 reduction reactions mediated by the RuII(edta) complexes is proposed. The role of the coordinated water molecule (by its absence or presence in the primary coordination sphere) in controlling the mechanistic pathways, outer-sphere or inner-sphere, is discussed.

Reduction of carbon dioxide into formic acid using transition metal complexes as catalysts is a research area of abiding importance. Although ruthenium(II) complexes as ‘molecular catalysts’ have received much attention, use of ruthenium(III) complexes in the selective reduction of carbon dioxide into formic acid has recently been explored. This review focuses on the recent research progress in the use of a ruthenium(III) complex containing the ‘edta’ ligand (edta4- = ethylenediaminetetraacetate) as catalyst or mediator in the catalytic, electro-catalytic and photocatalytic conversion of bicarbonate to formate selectively. Details of the reaction mechanism pertaining to the overall catalytic process are discussed.

Most of the extant studies on social enterprises have taken a static view of institutional complexity and assumed conflict between social and market logics as given. In this study, by taking a dynamic perspective and examining the conflict between social and professional logics, we examine the process of their hybridization and how institutional complexity evolves as they grow and professionalize. Based on our study of a hospital in India, we find that social enterprises operating in highly professionalized fields pass through phases of hybridization and professionals play a crucial role as carriers of alternative logics to social enterprises.

This review covers highlights of the work performed in the van Eldik group on inorganic reaction mechanisms over the past two decades in the form of a personal journey. Topics that are covered include, from NO to HNO chemistry, peroxide activation in model porphyrin and enzymatic systems, the wonder-world of RuIII(edta) chemistry, redox chemistry of Ru(iii) complexes, Ru(ii) polypyridyl complexes and their application, relevant physicochemical properties and reaction mechanisms in ionic liquids, and mechanistic insight from computational chemistry. In each of these sections, typical examples of mechanistic studies are presented in reference to related work reported in the literature.

This report provides our research progresses exploring the use of Ru(edta) complexes (edta4− = ethylenediaminetetraacetate) as a small-molecule model for mimicking the activity of the oxidoreductase family of enzymes (viz. oxidases, peroxidases, oxygenases, and reductases) in regard to small molecule activation (or transformation) with a focus on incorporating mechanistic information for a better understanding of the reaction pathways of such enzymatic reactions. Our research contributions reported herein show how the presence and absence of water molecule in the primary coordination sphere of the Ru(edta) complex governs the inner-sphere and outer-sphere pathways for the aforesaid enzyme mimicking activity of Ru(edta). Efforts were made to place our achievements into perspective along with the accomplishment of others.

The advancement of Ru(edta) complexes (edta4− = ethylenediamineteraacetate) mediated reactions, including NO generation and its utilization, has not been systematically reviewed to date. This review aims to report the research progress that has been made in exploring the application of Ru(edta) complexes in trapping and generation of NO. Furthermore, utilization of the potential of Ru(edta) complexes to mimic NO synthase and nitrite reductase activity, including thermodynamics and kinetics of NO binding to Ru(edta) complexes, their NO scavenging (in vitro), and antitumor activity will be discussed. Also, the role of [Ru(edta)(NO)] in mediating electrochemical reduction of nitrite, S-nitrosylation of biological thiols, and cross-talk between NO and H2S, will be covered. Reports on the NO-related chemistry of Fe(edta) complexes showing similar behavior are contextualized in this review for comparison purposes. The research contributions compiled herein will provide in-depth mechanistic knowledge for understanding the diverse routes pertaining to the formation of the [Ru(edta)(NO)] species, and its role in effecting the aforementioned reactions of biochemical significance.

The nitrite anion (NO2−) is an important source of nitric oxide (NO) or nitrosonium cations (NO+). In the present study, we have shown that [RuIII(edta)(NO+)] (edta4− = ethylendiaminetetraacetate) generated via decomposition of [RuIII(edta)(NO2)]2− at lower pH (3.5) could react with H2S to form a putative thionitrous acid (HSNO) bound Ru(edta) complex in aqueous solution. The reaction product [RuIII(edta)(NOSH)]− was characterized by IR, EPR and ESI-MS spectroscopy. Formation of N-coordinated [RuIII(edta)(NOSH)]− was further corroborated by DFT calculations.

The reduction of molecular oxygen (O

Electrochemistry of Ru(edta) complexes (edta4− = ethylenediaminetetraacetate) progressed over a period of several decades, with significant increase in understanding of the electro-catalytic processes involving the substrate coordinated to the metal center. While electrochemistry studies of many Ru(edta) complexes were published in several papers, no attempt has been made to provide a comprehensive and systematic overview of its electrochemical properties, evaluating its application to catalytic electrochemical transformation of small molecules. In this article, results of the electrochemical studies of both mononuclear and binuclear complexes of Ru(edta) are reviewed with regard to electron-transfer reaction mechanism and activity. Their potential to act as redox mediators or catalysts in electrochemical transformations of small molecules and enzymatic reactions, are highlighted. This review aims to contribute to the mechanistic understanding of Ru(edta) complexes in catalysis of such electrochemical transformations.

Soft-robotics is gradually emerging as one of the promising fields of research and innovation. Owing to the blend of material-chemistry and conventional mechanics, complex motions have been successfully generated by flexible polymeric composites that act upon external activation stimuli. However, lack of robust deterministic models which can command reliable actuator performance, hinder their widespread deployments in diverse paradigms. The present article seeks to address the argument by modelling Ionic Polymer Metal Composites (IPMC) as multi-segmented chains of connected rigid bodies. A Cyclic-Coordinate-Descent (CCD) based Inverse Kinematic solver is employed to resolve the redundancy, by minimizing an objective function in joint space at gradual iterative steps. The algorithm is validated for its ability to model dissimilarly doped polymeric curvatures bearing distinct spatial postures. The 2-D shape estimation problem is addressed to generate patterns akin to original IPMCs for deployment on potential applications that anticipate a foresight of actuator geometry.

The reaction of [RuIII(EDTA)(H2O/OH)]−/2− (EDTA4− = ethylenediaminetetraacetate) with bisulfide (HS−) and persulfide (HSS−) leading to the formation of a dinuclear disulfur-bridged [(EDTA)R...

In this article, we examine how leading business schools in India orient themselves locally and globally while pursuing conformity and distinctiveness. We expect that these dynamics are particularly complex in ‘emerging’ economies such as India where liberalization and subsequent economic resurgence have led to more intense global exposure for business schools. By exploring changes in the way these responses are applied over time, we identify four globalization routes in the field. Furthermore, we show that these routes make up two broad zones of global–local interaction. In one, we point to the ability of global practices to serve both global and local compulsions, leading to the diffusion of global norms and practices. In the other, we point to how inherent paradoxes lead to possibilities for moderate and radical global distinctiveness.

Ionic Polymer Metal Composites (IPMC) have emerged as an actuator for gripping soft as well as rigid objects, owing to their compliance and good scalability. Their use in precision gripping necessitates the absence of any ambivalence in its characterization to ensure grasp stability. This article proposes an alternative approach to model IPMCs, contrary to prior attempts that have employed cantilever deflection theories. The bending patterns of the actuator soaked in distilled water and LiCl solution are studied using a Tractrix based hyper-redundant kinematic algorithm. Two distinct gripper designs comprising of a conventional two jaw as well as a modified passive jaw gripper have been investigated to ascertain their traversed workspaces in the aforementioned mediums. A prior knowledge of this working-area ensures an effective design of target-specific gripper configurations adept to negotiate objects with varied surface profiles. The results obtained after experiments indicate that IPMCs infused in LiCl solution exhibit a characteristic curvilinearity, suited for ensuring surface contact with the object. However the ones hydrated in de-ionized water demonstrate linear bending, apt for generating point contact. Though the passive-jaw gripper showcases a smaller workspace with respect to the active ones, yet it conveys a vital information regarding the contact force exerted on an object surface by the polymer jaw.

[RuIII(EDTA)(H2O)]− (EDTA4− = ethylenediaminetetraacetate) catalyzes the oxidation of biological thiols, RSH (RSH = cysteine, glutathione, N-acetylcysteine, penicillamine) using H2O2 as precursor oxidant. The kinetics of the oxidation process were studied spectrophotometrically as a function of [RuIII(EDTA)(H2O)]−, [H2O2], [RSH], and pH (4–8). Spectral analyses and kinetic data are suggestive of a catalytic pathway in which the RSH reacts with [RuIII(EDTA)] catalyst complex to form [RuIII((EDTA)(SR)]2− intermediate species. In the subsequent reaction step the oxidant, H2O2, reacts directly with the coordinated S of the [RuIII((EDTA)(SR)]2− intermediate leading to formation of the disulfido (RSSR) oxidation product (identified by HPLC and ESI-MS studies) of thiols (RSH). Based on the experimental results, a working mechanism involving oxo-transfer from H2O2 to the coordinated thiols is proposed for the catalytic oxidation.

Ionic Polymer Metal Composites (IPMCs) has established itself as an ionomer rendering wide-ranging applications spanning the paradigm of robotics to medical appliances, thereby drawing significant research interests. Prior studies to characterize IPMCs have been conducted over several years but efforts on its kinematic modeling have remained inchoate. The bending profile of IPMC changes when placed in different ionic solutions. The IPMC trace along with its tip location characterizes its complete behavior upon low level actuation. This article aims at identifying the bending patterns of an IPMC actuator, decomposing it as a 20-link hyper-redundant serial manipulator. The Tractrix based inverse kinematics engine is used to study the polymer profile in distilled water, 1.5 N LiCl and NaCl solutions respectively. The proposed algorithm yields a natural curve (Tractrix) which resembles the profile traced by an actuated IPMC strip — enabling its use in potential applications which would require a foresight of the actuator workspace.

The reaction of hydrogen sulfide (H2S) and nitric oxide (NO) is of great physiological significance in human organisms. Our present studies show that Ru(III)(edta) (edta(4-) = ethylenediaminetetraacetate) mediates the S-nitrosylation of bisulfide ion (HS(-)) using NO to form [Ru(III)(edta)(SNO)](2-), the first-ever example of a ruthenium complex containing thionitrite (SNO(-)) in aqueous solution. The reaction product [Ru(III)(edta)(SNO)](2-) was characterized by IR, electron paramagnetic resonance, and electrospray ionization mass spectroscopy. Our studies further show that formation of the putative thionitrous acid coordinated to Ru(III)(edta) does not occur via the reaction of [Ru(III)(edta)NO](-) with HS(-).

The [RuIII(EDTA)(H2O)]− (EDTA4− = ethylenediaminetetraacetate) complex is shown to mediate the oxidation of thiols, RSH (RSH = cysteine, glutathione, N-acetylcysteine, and penicillamine), with peroxomonosulfate ion (HSO5−). The kinetics of the catalytic oxidation process were studied using stopped-flow and rapid scan spectrophotometry as a function of [RuIII(EDTA)(H2O)−], [HSO5−], and [RSH] at a constant pH (6.2). Spectral analyses and kinetic data are suggestive of a catalytic pathway in which the RSH reacts with the [RuIII(EDTA)] catalyst complex to form [RuIII(EDTA)(SR)]2− intermediate species. In a subsequent step the HSO5− ion reacts directly with the coordinated S-atom of [RuIII(EDTA)(SR)]2− yielding the disulfido species, RSSR, as a major oxidation product (as identified using HPLC and ESI-MS analyses) under the employed conditions. Based on the experimental data, a working mechanism is proposed for the [RuIII(EDTA)] catalyzed oxidation of thiols.

Reported in this paper is the first example of a ruthenium(III) complex, [RuIII(edta)] (edta4− = ethylenediaminetetraacetate), that catalyzes the conversion of bicarbonate to formate selectively over a visible light irradiated surface of carbon, nitrogen and sulfur doped TiO2 (represented as C–TiO2, N–TiO2 and S–TiO2, respectively) semiconductor photocatalyst particles. Formation of formate, the only reduction product, was identified by 13C NMR analysis of the reaction mixture. Based on the experimental findings a working mechanism involving activation of bicarbonate (HCO3−) through the formation of a [RuIII(edta)(HCO3)]2− intermediate complex followed by the photochemical reduction of the coordinated bicarbonate to produce formate at the surface of non-metal (C, N, S) doped TiO2 semiconductor particles is proposed. The efficacy of bicarbonate reduction over such photocatalysts decreased in the following order C–TiO2 > N–TiO2 > S–TiO2.

Although a substantial literature on the management of technological innovation exists, several scholars argue that much of this research has been rooted in Western contexts, where key assumptions are very different from those in emerging economies. Building on this viewpoint, we investigate the current state of knowledge on technological innovation in two of the largest and fastest growing emerging economies: China and India. We undertook a bibliometric analysis of author keywords and combined different quantitative approaches – frequency analysis, cluster analysis, and co-word analysis – to review 162 articles on technological innovation published about China and India for the period 1991–2015. From the analyses, the trends in technological innovation research in the two countries and the dominant themes of discussion were identified. These themes were further classified into eight sub-themes. Our key findings indicate a near absence of research on the management of technological innovation based on India, limited volume of research on indigenous aspects of innovation, and a lack of theory-building based on these countries’ contexts. Several suggestions for future research are offered based on the gaps identified.

The complex [RuIII(edta)(H2O)]− (edta4− = ethylenediaminetetraacetate) catalyzes the oxidation of captopril (CapSH) using primary oxidants, hydrogen peroxide (H2O2) and peroxomonosulfate ( $$ {\text{HSO}}_{5}^{ - } $$ ). The kinetics of the oxidation reaction were studied as a function of both oxidant (H2O2, $$ {\text{HSO}}_{5}^{ - } $$ ) and substrate (CapSH) concentrations using stopped-flow and rapid scan stopped-flow techniques. Spectral and kinetic data are suggestive of a pathway involving rapid formation of the intermediate complex [RuIII(edta)(CapS)]2− followed by direct attack of the oxidant (H2O2 or $$ {\text{HSO}}_{5}^{ - } $$ ) at the S atom of the coordinated CapS−. ESI–MS and HPLC analysis of the reaction products showed that captopril disulfide (CapSSCap) is the major oxidation product. A probable mechanism in agreement with the spectral and kinetic data is presented.

The reaction of [RuIII(edta)(SCN)]2− (edta4− = ethylenediaminetetraacetate; SCN− = thiocyanate ion) with the peroxomonosulfate ion (HSO5−) has been studied by using stopped-flow and rapid scan spectrophotometry as a function of [RuIII(edta)], [HSO5−], and temperature (15–30oC) at constant pH 6.2 (phosphate buffer). Spectral analyses and kinetic data are suggestive of a pathway in which HSO5− effects the oxidation of the coordinated SCN− by its direct attack at the S-atom (of SCN−) coordinated to the RuIII(edta). The high negative value of entropy of activation (ΔS≠ = −90 ± 6 J mol−1 deg−1) is consistent with the values reported for the oxygen atom transfer process involving heterolytic cleavage of the O-O bond in HSO5−. Formation of SO42−, SO32−, and OCN− was identified as oxidation products in ESI-MS experiments. A detailed mechanism in agreement with the spectral and kinetic data is presented.

Palash Eye Hospital was established with the aim of providing free eye care to the poor and affordable treatment to individuals with paying capacity in Calicut district of the State of Kerala in Southern India. Starting as the only specialty eye hospital of its kind in 1999, the hospital had grown over the last 10 years. It was operated on a cross-subsidy model where revenues from paid services were used for providing free treatment and funding expansion plans. The hospital was being managed by Palash Eye Care Trust while its community outreach activities were being handled by Palash Eye Care Society. With the entry of new commercial eye hospitals in the region, the hospital was facing competition for skilled resources and was falling behind on efficiency. The growth of the hospital was not accompanied with a corresponding development of structures and processes. The hospital was being run on the basis of informal relationships which could not be depended upon to manage a growing enterprise. Administrative control of the hospital lay in the hands of the Trust and Society members and was not shared with the medical staff. This had resulted in dissatisfaction on the part of doctors who wanted to be involved in the hospital administration in order to professionalize and increase hospital efficiency. Consequently, a conflict of interests emerged between the Trust and Society members on the one hand and the doctors on the other. Lack of established operating processes, career growth avenues, and reward and recognition systems was also creating discontent among the paramedical staff. At the same time, the failing health of the founder chairman was not allowing him to be actively involved in the hospital activities. Being a member of both the Trust and the Society, he was managing the interests of both groups in the hospital. In view of his decreased role, the problem of developing new interlocking mechanisms between the Trust and the Society was surfacing.

The complex [RuIII(edta)(H2O)]− (edta4− = ethylenediaminetetraacetate) catalyzes the oxidation of thiourea (TU) by peroxomonosulfate ion (HSO5 −). The kinetics of the catalytic oxidation process was studied by using stopped-flow and rapid-scan spectrophotometry as a function of [RuIII(edta)(H2O)−], [HSO5 −] and [TU] at a constant pH of 6.2 (phosphate buffer) and temperature of 25 °C. Spectral and kinetic data are suggestive of a catalytic pathway involving rapid formation of a [RuIII(edta)(TU)]− intermediate complex by reaction of [RuIII(edta)(H2O)]− with TU, followed by the oxidation of the coordinated TU in which HSO5 − reacts directly with the S atom of TU coordinated to the RuIII(edta) complex. Analysis of the reaction mixture at the end of the reaction revealed the formation of formamidine disulfide (TU2) as a major product; however, thiourea dioxide (TUO2) and sulfate were also observed if the reaction mixture was kept for longer time periods. A detailed mechanism in agreement with the spectral and kinetic data is presented.

Reaction of [RuIII(EDTA)(CyS)]2− (edta4− = ethylenediaminetetraacetate; CySH = cysteine) with molecular oxygen (O2) have been studied as a function of pH (4.0-8.0) and cysteine concentration (0.2-2.0 mM) at room temperature (25 °C). Biological activities of the [Ru(EDTA)]/CySH/O2 system pertaining to cleavage of supercoiled plasmid DNA to its nicked open circular form has been explored in this work. Results are discussed in regard to the reaction of the ruthenium(III)-complex with molecular oxygen) and a working mechanism is proposed for the biological activities of the ruthenium(III)-complex in the presence of O2.

Evidence suggests that in several emerging economies, technology commercialization by universities is not quite institutionalized. Given this backdrop, we studied how research commercialization co-varied with two aspects of organizational identities: their definitions and their orientations. Adopting a case methodology with a grounded approach, and using semi-structured interviews and archival data, we studied a specialized higher education institution in India which is involved in the research and commercialization of biomedical innovations. We found that the effectiveness of their research commercialization efforts appeared to co-vary with how organizational identities were defined, while their efforts directed towards public or private goods appeared to co-vary with how organizational identities were oriented. We suggest a set of propositions for future studies. We also suggest that policies in this field need to account for how organizational identity impacts research into public goods in these economies and the need to encode policy changes in the organizational identities of universities.

An effective procedure for selective reduction of O2 to H2O2 exploring the use of hydrogen sulfide, an obnoxious industrial pollutant as reductant is reported herein. The reduction of [Ru(III)(EDTA)pz](-) (EDTA(4-) = ethylenediaminetetraacetate; pz = pyrazine) by hydrogen sulfide resulting in the formation of a red [Ru(II)(EDTA)pz](2-) complex (λmax = 462 nm) has been studied spectrophotometrically and kinetically using both rapid scan and stopped-flow techniques. The time course of the reaction was followed as a function of [HS(-)]i, pH (5.5-8.5), and temperature. Alkali metal ions were found to have a positive influence (K(+) > Na(+) > Li(+)) on the reaction rate. Kinetic data and activation parameters are interpreted in terms of a mechanism (admittedly speculative) involving outer-sphere electron transfer between the reaction partners. Reaction of the red [Ru(II)(EDTA)pz](2-) complex with molecular oxygen regenerates the [Ru(III)(EDTA)pz](-) species in the reacting system along with the formation of H2O2, a partially reduced product of dioxygen (O2) reduction. A detailed reaction mechanism in agreement with the spectral and kinetic data is presented.

The different RuIII(EDTA) complexes (EDTA4− = ethylenediaminetetraacetate) formed in aqueous solution are prospective in many ways and have unique features that make them significant for biochemical applications. The advancement of RuIII(EDTA) mediated bioinorganic reactions in terms of unravelling their mechanistic information has not been systematically reviewed to date. Hence, the subject of this review comprises the most recent advances in RuIII(EDTA) chemistry with regard to bioinorganic reaction mechanisms involving RuIII(EDTA) complexes. This review mainly covers the application of RuIII(EDTA) complexes as catalysts or mediators in homogeneous reaction systems for the activation of redox signalling molecules, viz. H2O2, thiols (RSH), NO and H2S, highlighting the authors’ own recent studies on such catalytic systems. Details of the reaction mechanisms have been revealed for peroxide activation, thiol oxidation, S-nitrosylation of thiols, and dioxygen activation involving RuIII(EDTA) complexes. This review also covers progress in unravelling the mechanism of RuIII(EDTA) mediated oxidation of thiols using KHSO5 as a precursor oxidant.

In this paper, we present the first example of a ruthenium(III) complex, [RuIII(edta)] (edta = ethylenediaminetetraacetate), that catalyzes the electrochemical conversion of hydrogen carbonate to formate selectively. The formation of an [RuIII(edta)(HCO3)]2– species through the reaction of the [RuIII(edta)(H2O)]– catalyst and hydrogen carbonate (HCO3–) was studied kinetically by using the stopped-flow technique. The value of the second-order rate constant for the formation of the [RuIII(edta)(HCO3)]2– complex was 82 ± 7 M–1 s–1 at 25 °C and pH = 6.4. Electrochemical reduction of hydrogen carbonate (HCO3–) was achieved by carrying out constant-potential bulk electrolysis at –0.4 V (vs. SCE) with a mercury-pool cathode at pH = 6.4. The formation of formate as the only reduction product was evidenced by a 13C NMR analysis of the reaction mixture obtained after electrolysis.

Reported here is the first example of a ruthenium(iii) complex [Ru(III)(EDTA)(H2O)](-) (EDTA(4-) = ethylenediaminetetraacetate) that mediates S-nitrosylation of cysteine in the presence of nitrite at pH 4.5 (acetate buffer) and results in the formation of [Ru(III)(EDTA)(SNOCy)](-). The kinetics of the reaction was studied by stopped-flow and rapid-scan spectrophotometry as a function of [Cysteine], [NO2(-)] and pH (3.5-8.5). Formation of [Ru(III)(EDTA)(SNOCy)](-), the product of the S-nitrosylation reaction, was identified by ESI-MS experiments. A working mechanism in agreement with the spectroscopic and kinetic data is presented.

The Fe(III) complex, [FeIII(HQS)3] (HQS = 8-hydroxyquinoline-5-sulfonic acid), is found to effect sensitization of the large band gap semiconductor, TiO2. The role of interfacial electron transfer in sensitization of TiO2 nanoparticles by surface adsorbed [FeIII(HQS)3] was studied using femtosecond time scale transient absorption spectroscopy. Electron injection has been confirmed by direct detection of the electron in the conduction band. A TiO2-based dye-sensitized solar cell (DSSC) was fabricated using [FeIII(HQS)3] as a sensitizer, and the resulting DSSC exhibited an open-circuit voltage value of 425 mV. The value of the short-circuit photocurrent was found to be 2.5 mA/cm2. The solar to electric power conversion efficiency of the [FeIII(HQS)3] sensitized TiO2-based DSSC device was 0.75 %. The results are discussed in the context of sensitization of TiO2 by other Fe(II)-dye complexes.

Catalytic ability of [RuIII(edta)(H2O)]− (edta4− = ethylenediaminetetraacetate) complex toward oxidation of thiosulfate (S2O32−) in presence of H2O2 has been explored in the present work. The kinetics of the catalytic oxidation of thiosulfate (S2O32−) has been studied spectrophotometrically as a function of [RuIII(edta)], [H2O2], [S2O32−] and pH. Spectral analyses and kinetic data indicate a catalytic pathway involving activation of both substrate (S2O32−) and oxidant (H2O2). Substrate activation pathway involves the formation of a red [RuIII(edta)(S2O3)]3− species through the reaction of the [RuIII(edta)(H2O)]− catalyst complex and the substrate (S2O32−). Hydrogen peroxide reacts directly with thiosulfate coordinated to the RuIII(edta) complex to yield sulfite as immediate oxidation product. Peroxide activation pathway is governed by the formation of [RuV(edta)(O)]− catalytic intermediate which oxidize thiosulfate, however, at slower rate ( k ox 2 = 0.012 M − 1 s − 1 at 25 °C) as compared to the rate of oxidation of the coordinated thiosulfate ( k ox 1 = 0.93 M − 1 s − 1 at 25 °C). Sulfite and sulfate were found to be the oxidation products of the above described catalytic oxidation process. A detailed mechanism in agreement with the spectral and kinetic data is presented.

Nafion based IPMC (Ion Polymeric Metal Composites) has been prepared by using a tetraaquaplatinum (II) complex, [Pt (H2O)4])ClO4)2. Fabrication of a robotic mini-hand comprising five micro-fingers of 5 mm length, 400 μm width at a pitch of 600 μm has been achieved by adopting mechanicalmicro milling' technique. The micro-fingers prepared from the IPMC material were found to actuate successfully under operating voltage of 2.5 V.

The interaction of a RuIII(edta) complex (edta4− = ethylenediaminetetraacetate) with human apo-transferrin (apo-hTf) has been investigated using fluorescence spectroscopic techniques. The results of fluorescence spectral studies point towards static quenching involving binding of RuIII(edta) with apo-hTf. The value of the apparent binding constant (KA) estimated at physiological buffer is 4.72 × 104 M−1. Antiproliferative activity of RuIII(edta) in MCF-7 (breast carcinoma) cells was evidened by microculture tetrazolium test (MTT). Our results taken together are suggestive of the fact that the RuIII(edta) complex can bind to apo-hTf, and induce cell death by inhibiting NF-κB activation. The results of the computational based in silico analysis studies further suggest that the RuIII(edta) that binds apo-hTf to form the [Ru-edta-hTf] complex, for which the binding of [Ru-edta-hTf] complex with transfrrin receptor (TfR) takes place not at the usual binding domain, but in the other domain of the receptor. The alteration of the binding domain of transferrin with its receptor may inactivate the observed transferrin-transferrin receptor mediated biological functions.

This work introduces the concept of a novel thiocyanate ion (SCN-) detecting device. We show proof-of-principle of the device, namely IPMC film prepared by surface modification of the ionic-polymer film. In this work, naked-eye detection of thiocyanate ion (SCN-) by using iron exchanged ionic polymer-metal composites (IPMC) strip has been achieved. It was successfully applied to direct determination of thiocyanate at micro-molar level in water samples. The response time of the sensor in whole concentration ranges is very short (

Selective hydrogenation of bicarbonate to formate catalyzed by a ruthenium(III) complex, [RuIII(edta)] (edta4− = ethylenediaminetetraacetate), at moderate H2 pressure (2–8 atm) and temperature (30–40 °C) is reported. Formation of formate, the only reduction product, was identified by 13C NMR analysis of the resultant reaction mixture. Based on the spectral data, a working mechanism (admittedly speculative) involving the formation of ruthenium(III)-bicarbonate complex, [RuIII(edta)(HCO3)]2−, is proposed for the catalytic reaction.

In this work, we have developed a wrist band using Nafion based ionic polymer-metal composites (IPMC) for sensing the rhythm of human pulse bits. Each pulse bit produces dynamic deformation of IPMC band, and signals (voltage) are generated due to endo-ionic mobility inside the IPMC strip wrapped around the wrist. This work introduces the concept of a novel pulse bits rhythm sensing device. We show proof-of-principle of the mechano-electrical functions of the device, namely IPMC film prepared by surface platinization of the ionic-polymer film.