Simultaneous determination of theophylline and caffeine on novel [Tetra-(5-chloroquinolin-8-yloxy) phthalocyanato] manganese(III)-Carbon nanotubes composite electrode

This work reports the synthesis of new symmetrically substituted manganese(III) phthalocyanine (2eOHMnPc) (2) containing tetra 5-chloroquinolin-8-yloxy group at the peripheral position for the first time. Manganese(III) phthalocyanine (2) was synthesized by cyclotetramerization of 4-(5-chloroquinolin-8-yloxy)phthalonitrile (1) in the presence of corresponding metal salt (manganese(II) chloride). This peripherally substituted phthalocyanine complex (2) was purified by column chromatography and characterized by several techniques such as IR, mass and UV-Visible spectral data. This novel synthesized phthalocyanine was mixed with multiwalled carbon nanotubes in order to prepare the novel catalytic surface on glassy carbon electrode for theophylline and caffeine detection in acidic medium. The novel composite electrode surfaces were characterized by scanning electron microscopy and electrochemical impedance spectroscopy. Individual and simultaneous determination of theophylline and caffeine were studied by differential pulse voltammetry. The detection limits were individually calculated for theophylline and caffeine as 6.6 x 10(-9) M and 5.0 x 10(-8) M, respectively. In simultaneous determination, LODs were calculated for theophylline and caffeine as 8.1 x 10(-9) M and 3.0 x 10(-7) M, respectively. The practical applicability of the proposed modified electrode was tested for the determination of theophylline and caffeine in green tea, cola and theophylline serum

Simultaneous determination of theophylline and caffeine on novel [Tetra-(5-chloroquinolin-8-yloxy) phthalocyanato] manganese(III)-Carbon nanotubes composite electrode

WOS: 000432234900058PubMed ID: 29674068This work reports the synthesis of new symmetrically substituted manganese(III) phthalocyanine (2eOHMnPc) (2) containing tetra 5-chloroquinolin-8-yloxy group at the peripheral position for the first time. Manganese(III) phthalocyanine (2) was synthesized by cyclotetramerization of 4-(5-chloroquinolin-8-yloxy)phthalonitrile (1) in the presence of corresponding metal salt (manganese(II) chloride). This peripherally substituted phthalocyanine complex (2) was purified by column chromatography and characterized by several techniques such as IR, mass and UV-Visible spectral data. This novel synthesized phthalocyanine was mixed with multiwalled carbon nanotubes in order to prepare the novel catalytic surface on glassy carbon electrode for theophylline and caffeine detection in acidic medium. The novel composite electrode surfaces were characterized by scanning electron microscopy and electrochemical impedance spectroscopy. Individual and simultaneous determination of theophylline and caffeine were studied by differential pulse voltammetry. The detection limits were individually calculated for theophylline and caffeine as 6.6 x 10(-9) M and 5.0 x 10(-8) M, respectively. In simultaneous determination, LODs were calculated for theophylline and caffeine as 8.1 x 10(-9) M and 3.0 x 10(-7) M, respectively. The practical applicability of the proposed modified electrode was tested for the determination of theophylline and caffeine in green tea, cola and theophylline serum.Ege University Research Funds (BAP project)Ege University [12 FEN/039]; Research Fund of Karadeniz Technical University (Trabzon-Turkey)Karadeniz Teknik University [2010.111.002.1]This work was supported by Ege University Research Funds (BAP project, 12 FEN/039) and the Research Fund of Karadeniz Technical University, Project no: 2010.111.002.1 (Trabzon-Turkey)

The clinical, functional, and radiological features of hand osteoarthritis: TLAR-osteoarthritis multi-center cohort study

Objectives: This study aims to evaluate the clinical, functional, and radiological features of hand osteoarthritis (OA) and to examine their relationships in different geographic samples of the Turkish population. Patients and methods: Between April 2017 and January 2019, a total of 520 patients (49 males, 471 females; mean age: 63.6 +/- 9.8 years) with hand OA were included in the study from 26 centers across Turkey by the Turkish League Against Rheumatism (TLAR). The demographic characteristics, grip strengths with Jamar dynamometer, duration of hand pain (month), the severity of hand pain (Visual Analog Scale [VAS]), and morning stiffness were evaluated. The functional disability was evaluated with Duruoz Hand Index (DHI). The Kellgren-Lawrence (KL) OA scoring system was used to assess the radiological stage of hand OA. Results: The DHI had significant correlations with VAS-pain (r=0.367, p0.05). The differences between the groups of radiological hand OA grades in terms of age (p=0.007), VAS-pain (p0.05 for all). Conclusion: In our population, the patients with hand OA had pain, functional disability, and weak grip strength. The functional impairment was significantly correlated with the severity of the pain, and the functional status was worse in high radiological hand OA grades