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81.
A new immunoassay strategy for sensitive atrazine determination based on magnetic beads is reported. The immuno-method is a competitive solid-phase immunoassay where the anti-atrazine antibody is immobilized on the magnetic beads surface and fixed at the reaction cell bottom using a simple magnet, which generates a magnetic field. Analyte and HRP (horseradish peroxidase) tracer compete for active sites of antibody. After the immunointeractions antibody-analyte and antibody-tracer, atrazine quantification from the sample is performed by injection of the chemiluminescence substrate (luminol, hydrogen peroxide and p-iodophenol). Different antibodies (polyIgG anti-atrazine Ab I and affinity purified polyIgG anti-atrazine AbI) were tested in this configuration. Also, optimum concentration of antibody-covered magnetic beads was set up (8 mg/l Ab II). Finally, the performance of magnetic beads-based immunoassay for atrazine determination was evaluated demonstrating that the magnetic beads-based immunoassay is one of the most sensitive method for atrazine determination (LoD = 3 pg/l, IC50 = 37 pg/l, DR = 10-1000 pg/l). 相似文献
82.
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83.
Results are presented on the thermal behaviour of two derivatives of malic acid. The decomposition intermediates obtained at about 400?C were identified as derivatives of malonic acid. For some individual thermal decomposition steps, the values of the non-isothermal kinetic parameters were determined. 相似文献
84.
Paper-based analytical devices have become lately “must have” components in equipment and instrumental designed for point-of-care applications, especially when they are used in tandem with microfluidic platforms. Nowadays, paper-based electrochemical devices (PEDs) represent the first choice in the development of lab-on-a-chip biosensors because of their benefits in biomedical diagnosis in terms of simplicity, affordability, portability, and disposability. Moreover, cellulose is a biodegradable and biocompatible substrate, ideal for building disposable devices for use in remote locations or low-resource settings. Despite their low costs and simplicity, PEDs must face a tough challenge—meeting the affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, and deliverable to end users criteria. The latest achievements in microfluidic PEDs for clinical diagnosis will be critically discussed, putting emphasis on innovative assay formats and methods for surface modification. 相似文献
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86.
Maria Ignat Petrisor Samoila Cristina Coromelci Liviu Sacarescu Iuliean Asaftei Valeria Harabagiu Camelia Miron 《Comptes Rendus Chimie》2018,21(3-4):310-317
In the past years, an important problem that requires solutions at the global scale is the environmental pollution. This work describes a possible approach toward finding such solutions based on nanophotocatalysts with improved activity. Thus, the present study reports a new and efficient synthesis procedure for titania–zinc ferrite nanocomposite with enhanced photodegradation activity. The method is based on the liquid phase plasma technique and follows a bottom-up scheme. The resulted materials have been compared with those synthesized by the ultrasound-assisted method. Using the plasma-assisted procedures in the fabrication of an efficient nano(photo)catalyst decreases considerably the reaction time. The liquid phase plasma generates nanoparticles with enhanced structural, textural, and morphological properties as demonstrated by X-ray diffraction, nitrogen sorption, transmission electron microscopy, and small-angle X-ray scattering. 相似文献
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Camelia Henríquez Burkhard Horstkotte 《International journal of environmental analytical chemistry》2013,93(12):1236-1252
A multisyringe flow injection system (MSFIA) coupled to a gas-diffusion cell has been developed for the conductometric determination of ammonium in different water samples. Operation strategies, membrane, reagent concentrations, and flow rates have been studied to optimize the sensitivity of detection and to fit the required working range. The proposed MSFIA system has been compared with former FIA and SIA systems using gas diffusion. The system was applied to the determination of ammonium in water samples of different matrices in order to evaluate its performance. These samples were coastal waters, pond waters, and compost aqueous extracts. Good recoveries of 102?±?13% were obtained and no significant differences with the reference methods were found. The system can be used for a wide concentration range of ammonia, from 0.075 to 360?mg?L?1, without sample dilution and with a precision better than 2% of RSD. The throughput of the method was 32 injections per hour. 相似文献
89.
Corina Aramă Camelia Nicolescu Angela Nedelcu Crina-Maria Monciu 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(3-4):421-428
An inclusion complex between repaglinide and a cyclodextrin derivative, 7-sulfobutylether-β-cyclodextrin (Captisol®) was synthesized and characterized taking into account its possible benefits regarding the solubility, thus the bioavailability of repaglinide (an oral antidiabetic, carbamoyl methyl benzoic acid, practically insoluble in water, used for the treatment of type II diabetes mellitus). In order to establish the optimal conditions for the synthesis, phase-solubility studies were performed. Their results (AL type phase-solubility diagram), as well as the chromatographic retention behavior of repaglinide in the presence of Captisol® indicated that an 1:1 inclusion complex is formed. The estimated apparent stability constant, according to the Higuchi-Connors method is 530 M?1. These data were confirmed by 1H-NMR, IR, DTA of the inclusion complex prepared through lyophilization. 相似文献
90.
Georgescu Sergiu-Valeriu Coşereanu Camelia Fotin Adriana Brenci Luminiţa-Maria Costiuc Liviu 《Journal of Thermal Analysis and Calorimetry》2019,138(4):2505-2513
Journal of Thermal Analysis and Calorimetry - The research presented in this paper proposes structures of timber frame exterior walls using reed straws as insulation materials. Having thicknesses... 相似文献