A Highly Selective Chemosensor for Cyanide Derived from a Formyl-Functionalized Phosphorescent Iridium(III) Complex

A new phosphorescent iridium­(III) complex, bis­[2′,6′-difluorophenyl-4-formylpyridinato-<i>N</i>,<i>C</i>4′]­iridium­(III) (picolinate) (<b>IrC</b>), was synthesized, fully characterized by various spectroscopic techniques, and utilized for the detection of CN^– on the basis of the widely known hypothesis of the formation of cyanohydrins. The solid-state structure of the developed <b>IrC</b> was authenticated by single-crystal X-ray diffraction. Notably, the iridium­(III) complex exhibits intense red phosphorescence in the solid state at 298 K (Φ_PL = 0.16) and faint emission in acetonitrile solution (Φ_PL = 0.02). The cyanide anion binding properties with <b>IrC</b> in pure and aqueous acetonitrile solutions were systematically investigated using two different channels: i.e., by means of UV–vis absorption and photoluminescence. The addition of 2.0 equiv of cyanide to a solution of the iridium­(III) complex in acetonitrile (<i>c</i> = 20 μM) visibly changes the color from orange to yellow. On the other hand, the PL intensity of <b>IrC</b> at 480 nm was dramatically enhanced ∼5.36 × 10²-fold within 100 s along with a strong signature of a blue shift of the emission by ∼155 nm with a detection limit of 2.16 × 10^–8 M. The cyanohydrin formation mechanism is further supported by results of a ¹H NMR titration of <b>IrC</b> with CN^–. As an integral part of this work, phosphorescent test strips have been constructed by impregnating Whatman filter paper with <b>IrC</b> for the trace detection of CN^– in the contact mode, exhibiting a detection limit at the nanogram level (∼265 ng/mL). Finally, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed to understand the electronic structure and the corresponding transitions involved in the designed phosphorescent iridium­(III) complex probe and its cyanide adduct

A Highly Selective Chemosensor for Cyanide Derived from a Formyl-Functionalized Phosphorescent Iridium(III) Complex

A new phosphorescent iridium­(III) complex, bis­[2′,6′-difluorophenyl-4-formylpyridinato-<i>N</i>,<i>C</i>4′]­iridium­(III) (picolinate) (<b>IrC</b>), was synthesized, fully characterized by various spectroscopic techniques, and utilized for the detection of CN^– on the basis of the widely known hypothesis of the formation of cyanohydrins. The solid-state structure of the developed <b>IrC</b> was authenticated by single-crystal X-ray diffraction. Notably, the iridium­(III) complex exhibits intense red phosphorescence in the solid state at 298 K (Φ_PL = 0.16) and faint emission in acetonitrile solution (Φ_PL = 0.02). The cyanide anion binding properties with <b>IrC</b> in pure and aqueous acetonitrile solutions were systematically investigated using two different channels: i.e., by means of UV–vis absorption and photoluminescence. The addition of 2.0 equiv of cyanide to a solution of the iridium­(III) complex in acetonitrile (<i>c</i> = 20 μM) visibly changes the color from orange to yellow. On the other hand, the PL intensity of <b>IrC</b> at 480 nm was dramatically enhanced ∼5.36 × 10²-fold within 100 s along with a strong signature of a blue shift of the emission by ∼155 nm with a detection limit of 2.16 × 10^–8 M. The cyanohydrin formation mechanism is further supported by results of a ¹H NMR titration of <b>IrC</b> with CN^–. As an integral part of this work, phosphorescent test strips have been constructed by impregnating Whatman filter paper with <b>IrC</b> for the trace detection of CN^– in the contact mode, exhibiting a detection limit at the nanogram level (∼265 ng/mL). Finally, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed to understand the electronic structure and the corresponding transitions involved in the designed phosphorescent iridium­(III) complex probe and its cyanide adduct

A Highly Selective Chemosensor for Cyanide Derived from a Formyl-Functionalized Phosphorescent Iridium(III) Complex

A new phosphorescent iridium­(III) complex, bis­[2′,6′-difluorophenyl-4-formylpyridinato-<i>N</i>,<i>C</i>4′]­iridium­(III) (picolinate) (<b>IrC</b>), was synthesized, fully characterized by various spectroscopic techniques, and utilized for the detection of CN^– on the basis of the widely known hypothesis of the formation of cyanohydrins. The solid-state structure of the developed <b>IrC</b> was authenticated by single-crystal X-ray diffraction. Notably, the iridium­(III) complex exhibits intense red phosphorescence in the solid state at 298 K (Φ_PL = 0.16) and faint emission in acetonitrile solution (Φ_PL = 0.02). The cyanide anion binding properties with <b>IrC</b> in pure and aqueous acetonitrile solutions were systematically investigated using two different channels: i.e., by means of UV–vis absorption and photoluminescence. The addition of 2.0 equiv of cyanide to a solution of the iridium­(III) complex in acetonitrile (<i>c</i> = 20 μM) visibly changes the color from orange to yellow. On the other hand, the PL intensity of <b>IrC</b> at 480 nm was dramatically enhanced ∼5.36 × 10²-fold within 100 s along with a strong signature of a blue shift of the emission by ∼155 nm with a detection limit of 2.16 × 10^–8 M. The cyanohydrin formation mechanism is further supported by results of a ¹H NMR titration of <b>IrC</b> with CN^–. As an integral part of this work, phosphorescent test strips have been constructed by impregnating Whatman filter paper with <b>IrC</b> for the trace detection of CN^– in the contact mode, exhibiting a detection limit at the nanogram level (∼265 ng/mL). Finally, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed to understand the electronic structure and the corresponding transitions involved in the designed phosphorescent iridium­(III) complex probe and its cyanide adduct

Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970–2016: a systematic analysis for the Global Burden of Disease Study 2016

Background: Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016

Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

Background: The Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) provides a comprehensive assessment of risk factor exposure and attributable burden of disease. By providing estimates over a long time series, this study can monitor risk exposure trends critical to health surveillance and inform policy debates on the importance of addressing risks in context

Global, regional, and national incidence, prevalence, and years lived with disability for 328 diseases and injuries for 195 countries, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

Background: As mortality rates decline, life expectancy increases, and populations age, non-fatal outcomes of diseases and injuries are becoming a larger component of the global burden of disease. The Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) provides a comprehensive assessment of prevalence, incidence, and years lived with disability (YLDs) for 328 causes in 195 countries and territories from 1990 to 2016