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101.
102.
Afsaneh Amiri Eui Yul Choi Huyn Jeong Kim 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(1-2):185-194
The developments of immunosensors with a variety of formats are increasingly finding applications in clinical diagnostics and biological researches. A strategy for the immunoassay and preparation of Calixcrownchips is proposed. This strategy is based on the immobilization of antigens or antibodies on the surface of Calixcrown and the direct electrochemistry of horseradish peroxidase (HRP) that was labeled to an antibody or antigen, with its activity determined by using tetramethylbenzidine (TMB) as an electrochemical substrate. The present study includes general considerations of the competitive immunoreaction protocols. Alanine aminotransferase (ALT) monoclonal antibody (anti-ALT-mAb) was successfully immobilized on thiol derivative of Calixcrown fixed to a gold surface. ALT antigen was detected by competitive immunoreactions based on microarrays of anti-ALT-mAb or antigen immobilized on the surface of the Calixcrownchip. For the anti-ALT-mAb immobilized microarray the dynamic range is 0.05 ng/mL–10 μg/mL, the detection limit is 0.05 ng/mL and the sensitivity is 10 nA/(ng/mL) respectively. The Calixcrownchip immunosensor microarray provided much better technical performance than a comparable enzyme sensor with immobilized-anti-ALT-mAb. To investigate the complexation site, the structures of the complexes formed between the crown-5-ether moiety of Calix[4]arene and protonated Arginine and Lysine were determined by minimizing the complex formation energies. The complex stability depends on the number of amine groups in the alkyl chain of the amino acid and also the number of methylene groups between the amine groups of the amino acid. 相似文献
103.
Armand Blaschette Elke Wieland Gerlinde Seurig Dietrich Koch Firouz Safari 《无机化学与普通化学杂志》1983,506(11):75-86
Investigations on Bis(methylsulfonyl)-amine (Dimesylamine). III. Onium Salts of Dimesylamine Thirty-five salts of the strong acid HN(SO2Me)2 containing onium cations are reported. These include higher quaternary ammonium salts which show excellent solubility in solvents of low polarity, thus being particularly useful for preparing solutions of “naked” (MeSO2)2N? or corresponding ion-pairs. Pyrolysis of the quaternary ammonium salts at temperatures of 200—250°C produces tertiary amines and N-alkyl-dimesylamines by (N → N′)-alkyl transfer. Alkene formation is not observed. 相似文献
104.
Heravi Majid M. Malakooti Reihaneh Kafshdarzadeh Kosar Amiri Zahra Zadsirjan Vahideh Atashin Hassan 《Research on Chemical Intermediates》2022,48(1):203-234
An eco-friendly method for diversity-oriented synthesis of substituted dihydropyrano[2,3-c]pyrazole and benzylpyrazolyl coumarin derivatives has been achieved via one-pot and multicomponent reaction in the presence of PdO/Al-SBA-15 as an efficient and recyclable catalyst in H2O/EtOH under reflux conditions. The significant merits of this method are wide scope, high yields of the desired products, short reaction times and simple workup procedure. In addition, this nanocatalyst was simply recovered and reused five times without significant loss in catalytic activity and also performance.
Graphical abstract 相似文献105.
Alireza Ghassempour Nahid Mashkouri Najafi Ali Asghar Amiri 《Journal of Analytical and Applied Pyrolysis》2003,70(2):3103-261
Rapid and sensitive determination of citric acid in fermentation media by pyrolysis mass spectrometry (Py–MS) is proposed. Owing to high specificity of this method, distinguishing the citric acid from the matrix and by-products formed in the Krebs cycle is possible. Selected ion monitoring (SIM) mode is used for quantitative measurements, in which mass to charge (m/z) values of 175 of citric acid and 138 of 3-nitroaniline as internal standard are chosen. Limit of detection (LOD) for this method has been found to be 1 ng ml−1 and the linear working range was 10 ng ml−1–100 mg ml−1. Relative standard deviation (R.S.D.) of the method for five replicates was 0.84%. Results of Py–MS are compared with those obtained by UV–vis spectrophotometric method. Also, factor analysis is used for evaluating the influence of pH, molasses concentration, time and shaker intensity on the production of citric acid by Aspergillus niger. 相似文献
106.
Firouz Matloubi?MoghaddamEmail author Gholam R.?Koozehgiri Mohammad G.?Dekamin 《Monatshefte für Chemie / Chemical Monthly》2004,135(7):849-851
Summary. Combination of sodium saccharin and tetrabutylammonium iodide as a novel anionic catalyst system promotes selectively the trimerization of isocyanates to give symmetrical isocyanurates under solvent-free conditions.Present Address: College of Chemistry, Isfahan University of Technology, Isfahan, 84154, Iran 相似文献
107.
Ali Jebali Seyedhossein Hekmatimoghaddam Aliasghar Behzadi Iraj Rezapor Bahador Haji Mohammadi Tahereh Jasemizad Seyed Ali Yasini Morteza Javadzadeh Asiye Amiri Mansoure Soltani Zeynab Rezaei Najme Sedighi Mina Seyfi Mohammad Rezaei Mehran Sayadi 《Cellulose (London, England)》2013,20(6):2897-2907
In this study, cellulose nanoparticles were prepared by acid hydrolysis, separately conjugated with allicin and lysozyme by a carbodiimide cross-linker, and characterized by scanning electron microscopy, dynamic light scattering, and Fourier transform infrared spectroscopy. Then, their antimicrobial properties were evaluated by the microdilution method and compared with allicin, lysozyme, and nanocellulose alone. The results showed that nanocellulose had few antimicrobial activities, but allicin-conjugated nanocellulose (ACNC) and lysozyme-conjugated nanocellulose (LCNC) had good antifungal and antibacterial effects against standard strains of Candida albicans, Aspergillus niger, Staphylococcus aureus, and Escherichia coli. Noticeably, although allicin and lysozyme had different minimum inhibitory concentrations (MICs) against all strains, the same quantity of MIC50 and MIC90 was observed for both ACNC and LCNC. The authors suggest that both ACNC and LCNC can be used in industries as an antimicrobial agent in food packaging, inside foodstuffs, and in textile materials. 相似文献
108.
109.
110.
Mohammad Ehsan Taghavizadeh Yazdi Simin Nazarnezhad Seyed Hadi Mousavi Mohammad Sadegh Amiri Majid Darroudi Francesco Baino Saeid Kargozar 《Molecules (Basel, Switzerland)》2021,26(6)
The use of naturally occurring materials in biomedicine has been increasingly attracting the researchers’ interest and, in this regard, gum tragacanth (GT) is recently showing great promise as a therapeutic substance in tissue engineering and regenerative medicine. As a polysaccharide, GT can be easily extracted from the stems and branches of various species of Astragalus. This anionic polymer is known to be a biodegradable, non-allergenic, non-toxic, and non-carcinogenic material. The stability against microbial, heat and acid degradation has made GT an attractive material not only in industrial settings (e.g., food packaging) but also in biomedical approaches (e.g., drug delivery). Over time, GT has been shown to be a useful reagent in the formation and stabilization of metal nanoparticles in the context of green chemistry. With the advent of tissue engineering, GT has also been utilized for the fabrication of three-dimensional (3D) scaffolds applied for both hard and soft tissue healing strategies. However, more research is needed for defining GT applicability in the future of biomedical engineering. On this object, the present review aims to provide a state-of-the-art overview of GT in biomedicine and tries to open new horizons in the field based on its inherent characteristics. 相似文献