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121.
Ali Asghar Hatamnia Arman Rostamzad Nasser Abbaspour Reza Darvishzadeh Parviz Malekzadeh 《Natural product research》2016,30(5):600-604
Leaves of 10 Bene genotypes were collected from six provinces (West Azerbaijan, Kurdistan, Kermanshah, Ilam, Hamedan and Lorestan) in Iran. This study was carried out to better characterise the total phenolic and flavonoid contents, antioxidant capacity and phenolic composition, as well as to evaluate the correlation between content of phenolic compounds and antioxidant activity in 10 genotypes of Bene. The antioxidant activity of leaf extracts was measured using different assays: ferric reducing antioxidant power, nitric oxide radical scavenging and 2,2-diphenyl-1-picrylhydrazyl. The results indicated that the antioxidant capacity can be related to total phenolic and flavonoid content, so that among all the genotypes studied here, the highest and the lowest phenolic content and antioxidant activity were observed in B2 and B10 genotypes, respectively. Analysing the phenolic composition using high performance liquid chromatography, caffeic acid, vanillic acid, ferulic acid and sinapic acid were found in all investigated genotypes. 相似文献
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124.
Molecularly imprinted polymer based potentiometric sensor for the determination of hydroxyzine in tablets and biological fluids 总被引:1,自引:0,他引:1
Javanbakht M Fard SE Mohammadi A Abdouss M Ganjali MR Norouzi P Safaraliee L 《Analytica chimica acta》2008,612(1):65-74
Molecular imprinting is a useful technique for the preparation of functional materials with molecular recognition properties. In this work, a biomimetic potentiometric sensor, based on a non-covalent imprinted polymer, was fabricated for the recognition and determination of hydroxyzine in tablets and biological fluids. The molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization, using hydroxyzine dihydrochloride as a template molecule, methacrylic acid (MAA) as a functional monomer and ethylene glycol dimethacrylat (EGDMA) as a cross-linking agent. The sensor showed a high selectivity and a sensitive response to the template in aqueous system. The MIP-modified electrode exhibited a Nernstian response (29.4 ± 1.0 mV decade−1) in a wide concentration range of 1.0 × 10−6 to 1.0 × 10−1 M with a lower detection limit of 7.0 × 10−7 M. The electrode demonstrated a response time of ∼15 s, a high performance and a satisfactory long-term stability (more than 5 months). The method has the requisite accuracy, sensitivity and precision to assay hydroxyzine in tablets and biological fluids. 相似文献
125.
Mohammad M. Khodaei Parvin Ghanbary Iraj Mohammadpoor‐Baltork Hamid R. Memarian Ahmad R. Khosropour Kobra Nikoofar 《Journal of heterocyclic chemistry》2008,45(2):377-381
126.
Monireh Khadem Farnoush Faridbod Parviz Norouzi Abbas Rahimi Foroushani Mohammad Reza Ganjali Seyed Jamaleddin Shahtaheri 《Journal of the Iranian Chemical Society》2016,13(11):2077-2084
Dicloran pesticide is used to inhibit the fungal spore germination for different crops. Because of the increasing application of pesticides, reliable and accurate analytical methods are necessary. The aim of this work is designing the highly selective sensor to determine the dicloran in biological and environmental samples. Multi-walls carbon nanotubes and a molecularly imprinted polymer (MIP) were used as modifiers in the sensor composition. A dicloran MIP and a nonimprinted polymer (NIP) were synthesized and applied in the carbon paste electrode. After the optimization of electrode composition, it was used to determine the concentration of analyte. Parameters affecting the sensor response were optimized, such as sample pH, electrolyte concentration and its pH, and the instrumental parameters of square wave voltammetry. The MIP-CP electrode showed very high recognition ability in comparison with NIP-CP. The obtained linear range was 1 × 10?6 to 1 × 10?9 mol L?1. The detection limit was 4.8 × 10?10 mol L?1. This sensor was used to determine the dicloran in real samples (human urine, tap and river water samples) without special sample preparation before analysis. All important parameters were optimized, improving the sensor response considerably. 相似文献
127.
Shiripoure Ganjineh Ketab Roghayeh Tafvizi Farzaneh Khodarahmi Parvin 《Journal of Cluster Science》2021,32(5):1389-1399
Journal of Cluster Science - Since green synthesis of silver nanoparticles (AgNPs) is a simple, safe, cost-effective and eco-friendly method, AgNPs appear to be promising anti-cancer agents in the... 相似文献
128.
Differential optical absorption spectroscopy-based refractive index sensor for cancer cell detection
Parvin Tarunnum Ahmed Kawsar Alatwi Aadel M. Rashed Ahmed Nabih Zaki 《Optical Review》2021,28(1):134-143
Optical Review - A novel spectroscopic optical sensor is presented for cancerous cell detection in various parts of the human body (i.e., cervix, adrenal gland, breast, skin, and blood). An... 相似文献
129.
One‐pot Synthesis of Highly Functionalized Tetrahydropyridines: A Camphoresulfonic Acid Catalyzed Multicomponent Reaction
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A simple and straight forward solvent free method for the synthesis of a series of highly functionalized tetrahydropyridine derivatives has been achieved via multicomponent reaction of aromatic aldehydes, various amines, and β‐keto esters at room temperature using readily available (±)‐camphor‐10‐sulfonic acid as an organocatalyst. The current protocol offers an atom economic and environmentally benign method for the synthesis of the title compounds under solvent free conditions in good yields with high substrate scope and avoids column chromatographic purification. 相似文献
130.
Mohammad Ali Rasouli Mohammad Mahdavi Mina Saeedi Parviz Rashidi Ranjbar Abbas Shafiee Alireza Foroumadi 《Journal of heterocyclic chemistry》2015,52(2):386-391
The present study provides an efficient strategy for the preparation of novel N‐substituted‐4‐methyl‐quinolin‐1(2H)‐one derivatives via two‐step Ugi/Heck reaction. The procedure is based on the Ugi coupling between 2‐bromoanilines, various aromatic aldehydes, vinylacetic acid, and isocyanides, and then intramolecular Heck reaction, which leads to the formation of the title compounds in good yields. 相似文献