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An immunosensor is based on the signal measurement obtained upon the reaction of an antibody antigen complex. It plays a significant role in various fields such as environmental analysis, production monitoring, drug detection or screening, veterinary medicine, and animal food. In this study, an antibody crosslinked graphen oxide (GO)‐based potentiometric sensor has been developed for fast, simple, and economical detection of clenbuterol. In this context, the photosensitive amino acid bound GO platform is synthesized and used for the preparation of electrode material. Then, polymeric structure is characterized by infrared spectroscopy, and the performance of immunonano platform prepared by potentiometric sensor is evaluated. The effect of pH, response time, selectivity, and sensitivity is investigated. Under the optimized conditions, a simple and rapid method for the determination of clenbuterol from milk sample is established by immuno‐potentiometric sensor. The detection limit has found to be 0.87 × 10−9 mmol L−1 for this immuno‐potentiometric sensor. This immuno‐potentiometric sensor has optimum pH at 7.0, a wide linear response (1.0 × 10−2 to 1.0 × 10−9 mmol L−1), rapid response time (2 Min) and 36 weeks operational lifetime. [ABSTRACT FROM AUTHOR]

The use of continuous flow systems in chemical synthesis provides great advantages in terms of sustainability, efficiency, and safety. The ability to control reaction parameters such as temperature, pressure, and catalyst exposure in flow system enables rapid optimization of reaction conditions. In the present study, palladium complexes of 1‐(piridin‐2‐il)‐1H‐benzo[d][1,2,3]triazol, N‐((1H‐benzo[d][1,2,3]triazol‐1‐il)metil)piridin‐2‐amin, and (1H‐benzo[d][1,2,3]triazol‐1‐yl)(pyridin‐2‐yl)methanone ligands were synthesized and characterized. The catalytic activities of complexes are investigated in the hydrogenation of various alkenes such as styrene, cyclohexene, and 1‐octene under continuous flow conditions. The complexes showed very high activity at 10‐bar H2 pressure and 50°C for short periods of 5–10 min. The catalysts reused for 10 cycles with no significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

Furan-3-one derivatives 1 were converted into 2-hydroxy-pyrrole-3-ones 4 by reacting with various α- and β-amino acids. In contrast, the reaction of furan-3-ones and 1-aminocyclobutanecarboxylic acid afforded spiro-pyrrolo[2,1- b][1,3]oxazoles 5 via the pyrrole-3-one under the same reaction conditions. Some of 2-hydroxy-pyrrole-3-ones 3 derived from anthranilic acids were transformed to pyrrolo[1,2- a][3,1]benzoxazines via . [ABSTRACT FROM AUTHOR]

Lysozyme (Lys), also known as muramidase or N-acetylmuramide glycanhydrolase, is a family of enzymes that damage bacterial cell walls by catalyzing the hydrolysis of 1,4-β-linkages between N-acetylmuramic acid and N-acetyl- D-glucosamine residues in a peptidoglycan and between N-acetyl- D-glucosamine residues in chitodextrins. In this study, Lys was enhanced with a photosensitive facility by ruthenium chelate based monomers with a photosensitization and conjugation approach [amino acid (monomer) decorated and light underpinning conjugation approach]. Then, photosensitive Lys was allowed to interact with methacryloyl amido tyrosine (MATyr) monomer, which included tyrosine parts in its structure similar to those in the Lys structure. Two different types of cryogels including Lys-MATyr in their macropores were synthesized, Lys-MATyr cryogel and Lys-MATyr-clay cryogel. These two materials were used for the measurement of the antibacterial activity on Gram-positive and Gram-negative bacteria. The effects of the modified Lys on Staphylococcus aureus and Micrococcus luteus were determined with a dilution plate method. The effects on Escherichia coli and S. aureus were determined with a turbidity method. According to the data, the Lys-MATyr-clay modified embedded cryogel was effective on Gram-positive bacteria, and the Lys-MATyr modified embedded cryogel was so effective on Gram-negative bacteria. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Demirci MS, Toz H, Yılmaz F, Ertilav M, Asci G, Ozkahya M, Zeytinoglu A, Nart D, Ok E. Risk factors and consequences of post-transplant diabetes mellitus. Clin Transplant 2010 DOI: 10.1111/j.1399-0012.2010.01247.x. © 2010 John Wiley & Sons A/S. Background: The aim of this study is to investigate the clinical course as well as risk factors and prognosis of post-transplant diabetes mellitus (PTDM). Methods: Five hundred fifty-five kidney transplant recipients were retrospectively evaluated. PTDM was defined as fasting blood glucose ≥140 mg/dL on at least two consecutive measurements or requirement of oral antidiabetic drug or insulin. Patients with PTDM were divided into subgroups according to time of onset (early; <90 d vs. late, ≥90 d) and duration of diabetes (transient, <90 d vs. sustained ≥90 d). Results: The frequency of PTDM was 18.3%. In multivariate analysis age (p < 0.001), hepatitis C virus (HCV) infection (p < 0.05) and tacrolimus use (p < 0.001) were independent risk factors. Among 220 HCV+ patients, liver biopsy was performed in 158, the histological grade (3.3 ± 2.8 vs. 4.4 ± 3.1) and stage (0.9 ± 1.1 vs. 1.4 ± 1.2) were significantly more severe in patients with PTDM than in non-diabetics. Incidence of PTDM in patients with severe fibrosis was 46.7%; 19.2% in nil or mild fibrosis (p < 0.05). Patient and graft survival were significantly worse, and cardiovascular events and life-threatening infection episodes were more frequent in PTDM. Half of the patients had early PTDM, while 30.3% of patients with PTDM showed transient nature. Five- and 10-yr death censored graft survival rates were worse in transient subgroup compared with sustained patients with diabetes (log rank 0.025) whereas there was no difference in outcome between early and late subgroups. Conclusions: Age, tacrolimus, and HCV are independent risk factors for PTDM. PTDM has a negative impact on both patient and graft survival, irrespective of the time of onset and duration of diabetes. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, [Zn(2)(C(7)H(4)FO(2))(4)(C(6)H(6)N(2)O)(2)]·C(7)H(5)FO(2), consists of a binuclear Zn(II) complex bridged by two carboxyl groups of 2-fluoro-benzoate (FB) anions and a 2-fluoro-benzoic acid mol-ecule. The two bridging FB anions, one chelating FB anion and one nicotinamide (NA) ligand coordinate to one Zn cation with a distorted square-pyramidal geometry, while the two bridging FB anions, one monodentate FB anion and one NA ligand coordinate to the other Zn cation with a distorted tetra-hedral geometry. Within the binuclear mol-ecule, the pyridine rings are oriented at a dihedral angle of 19.41 (14)°. In the crystal structure, the uncoordinated 2-fluorobenzoic acid mol-ecules are linked by O-H⋯O hydrogen bonding, forming centrosymmetric supra-molecular dimers. Inter-molecular N-H⋯O hydrogen bonds link the complex mol-ecules into a three-dimensional network. The π-π contacts between nearly parallel pyridine and benzene rings [dihedral angles of 19.41 (14) and 12.72 (16)°, respectively, centroid-centroid distances = 3.701 (2) and 3.857 (3) Å] may further stabilize the crystal structure. The fluorine atoms in two FB ligands are disordered over two positions, with occupancy ratios of 0.70:0.30.

The asymmetric unit of the title Cd(II) complex, [Cd(C(8)H(5)O(3))(2)(C(6)H(6)N(2)O)(2)(H(2)O)]·H(2)O, contains two 4-formyl-benzoate (FB), two isonicotinamide (INA) ligands, one coordinated and one uncoordinated water mol-ecule; the FB ions act as bidentate ligands. The coordination number of the Cd(II) atom is seven within a CdO(5)N(2) donor set. Intra-molecular O-H⋯O hydrogen bonds link the uncoordinated water mol-ecules to the carboxyl groups. The dihedral angle between the carboxyl-ate groups and the adjacent benzene rings are 17.53 (13) and 16.55 (14)°. In the crystal structure, inter-molecular O-H⋯O, N-H⋯O, N-H⋯N and C-H⋯O hydrogen bonds link the mol-ecules into a supra-molecular structure. The amide group of one of the INA ligands is disordered over two orientations, with an occupancy ratio of 0.759 (3):0.241 (3).

In the title compound, [Zn(C(8)H(5)O(3))(2)(C(6)H(6)N(2)O)](n), the Zn(II) ion is tetrahedrally coordinated by two formyl-benzoate (FB) and one isonicotinamide (INA) ligands while symmetry-related FB ligands bridge adjacent Zn(II) ions, forming polymeric chains along the b axis. The carboxyl-ate groups in the two FB ions are twisted away from the attached benzene ring by 9.07 (2) and 26.2 (2)°. The two benzene rings of the FB ions are oriented at a dihedral angle of 81.30 (5)°. In the crystal, adjacent polymeric chains inter-act via N-H⋯O and C-H⋯O hydrogen bonds, π-π contacts between the formyl-benzoate rings [centroid-centroid distance = 3.7736 (8) Å] and weak C-H⋯π inter-actions, forming a three-dimensional network.

The title mol-ecule, [Zn(2)(C(8)H(8)NO(2))(4)(C(10)H(14)N(2)O)(2)]·2H(2)O, is a centrosymmetric binuclear complex, with two Zn(II) ions [Zn⋯Zn' = 2.9301 (4) Å] bridged by four methyl-amino-benzoate (MAB) ligands. The four nearest O atoms around each Zn(II) ion form a distorted square-planar arrangement with the distorted square-pyramidal coordination completed by the pyridine N atom of the N,N-diethyl-nicotinamide (DENA) ligand. Each Zn(II) ion is displaced by 0.3519 (2) Å from the plane of the four O atoms, with an average Zn-O distance of 2.030 Å. The dihedral angles between carboxyl-ate groups and adjacent benzene rings are 10.57 (10) and 16.63 (12)°, while the benzene rings are oriented at a dihedral angle of 81.84 (5)°. The pyridine ring is oriented at dihedral angles of 40.49 (6) and 51.25 (6)° with respect to the benzene rings. In the crystal structure, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. The π-π contact between the inversion-related pyridine rings [centroid-centroid distance = 3.633 (1) Å] may further stabilize the crystal structure.

The asymmetric unit of the crystal structure of the title complex, [Co(C(6)H(6)N(2)O)(2)(H(2)O)(4)](C(8)H(5)O(3))(2)·2H(2)O, contains one-half of the complex cation with the Co(II) ion located on an inversion center, a 4-formyl-benzoate (FB) counter-anion and an uncoordinated water mol-ecule. The four O atoms in the equatorial plane around the Co(II) ion form a slightly distorted square-planar arrangement with an average Co-O bond length of 2.086 Å; the slightly distorted octa-hedral coordination is completed by the two N atoms of the isonicotinamide (INA) ligands at a slightly longer distance [2.1603 (14) Å] in the axial positions. The dihedral angle between the carboxyl-ate group and the attached benzene ring is 5.93 (13)°, while the pyridine and benzene rings are oriented at a dihedral angle of 3.09 (6)°. In the crystal structure, O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. π-π Contacts between the benzene and pyridine rings [centroid-centroid distance = 3.758 (1) Å] may further stabilize the crystal structure.

In the centrosymmetric binuclear title complex, [Zn(2)(C(11)H(14)NO(2))(4)(C(10)H(14)N(2)O)(2)], the two Zn(II) ions [Zn⋯Zn = 2.8874 (3) Å] are bridged by four 4-(diethyl-amino)benzoate (DEAB) ligands. The four nearest O atoms around each Zn(II) ion form a distorted square-planar arrangement, the distorted square-pyramidal coordination being completed by the pyridine N atom of an N,N-diethyl-nicotinamide (DENA) ligand at a distance of 2.0484 (12) Å. The dihedral angle between the benzene ring and the carboxyl-ate group is 4.89 (6)° in one of the independent DEAB ligands and 7.13 (7)° in the other. The benzene rings of the two independent DEAB ligands are oriented at a dihedral angle of 86.58 (5)°. The pyridine ring is oriented at dihedral angles of 31.17 (4) and 58.38 (4)° with respect to the two benzene rings. In the crystal, weak inter-molecular C-H⋯O inter-actions link the mol-ecules into a three-dimensional network. Two weak C-H⋯π inter-actions are also present. The two ethyl groups of one of the DEAB ligands are disordered over two orientations, with occupancy ratios of 0.798 (5):0.202 (5) and 0.890 (5):0.110 (5).

The title Ni(II) complex, [Ni(C(7)H(4)BrO(2))(2)(C(6)H(6)N(2)O)(2)(H(2)O)(2)], is centrosymmetric. It contains two 2-bromo-benzoate (BB) ligands, two nicotinamide (NA) ligands and two water mol-ecules, all of them being monodentate. The four O atoms in the equatorial plane around the Ni atom form a slightly distorted square-planar arrangement, while the slightly distorted octa-hedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl-ate group and the adjacent benzene ring is 30.81 (17)°, while the pyridine and benzene rings are oriented at a dihedral angle of 84.66 (6)°. In the crystal structure, O-H⋯O and N-H⋯O hydrogen bonds link the mol-ecules into a supra-molecular structure. A weak C-H⋯π inter-action is also found.

In the monomeric centrosymmetric title Ni(II) complex, [Ni(C(7)H(4)BrO(2))(2)(C(10)H(14)N(2)O)(2)(H(2)O)(2)], the Ni(II) ion is located on an inversion center. The asymmetric unit contains one 2-bromo-benzoate ligand, one diethyl-nicotinamide (DENA) ligand and one coordinated water mol-ecule. The four O atoms in the equatorial plane around the Ni(II) ion form a slightly distorted square-planar arrangement, while the slightly distorted octa-hedral coordination is completed by two N atoms of two DENA ligands in the axial positions. The dihedral angle between the benzene ring and the attached carboxyl-ate group is 87.73 (15)°, while the pyridine and benzene rings are oriented at a dihedral angle of 42.48 (7)°. In the crystal structure, O-H⋯O hydrogen bonds link the mol-ecules into a two-dimensional network parallel to (10). In addition, C-H⋯O hydrogen bonds are observed.