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101.
102.
In this study, an impedimetric immunosensor based on polymer poly(thiophene)‐graft‐poly(methacrylamide) polymer (P(Thi‐g‐MAm)) modified indium tin oxide (ITO) electrode is developed for the detection of the Neuron Specific Enolase (NSE) cancer biomarker. First, the P(Thi‐g‐MAm) polymer is synthesized and coated on the ITO electrode by using a spin‐coating technique. P(Thi‐g‐MAm) polymer acts as an immobilization platform for immobilization of NSE‐specific monoclonal antibodies. Anti‐NSE antibodies are utilized as biosensing molecules and they bind to the amino groups of P(Thi‐g‐Mam) polymer via glutaraldehyde cross‐linking. Spin‐coating technique is employed for bioelectrode fabrication and this technique provides a thin and uniform film on the ITO electrode surface. This bioelectrode fabrication technique is simple and it generates a suitable platform for large‐scale loadings of anti‐NSE antibodies. This immunosensor exhibits a wide linear detection range from 0.02 to 4 pg mL?1 and with an ultralow detection limit of 6.1 fg mL?1. It reveals a good long‐term stability (after 8 weeks, 78% of its initial activity), an excellent reproducibility (1.29% of relative standard deviation (RSD)), a good repeatability (5.55% of RSD), and a high selectivity. In addition, the developed immunosensor is proposed as a robust diagnostic tool for the clinical detection of NSE and other cancer biomarkers. 相似文献
103.
Donovan Diane Price Aiden Rao Asha Üsküplü Elif ŞYazıcı Emine 《Journal of Algebraic Combinatorics》2022,55(1):259-275
Journal of Algebraic Combinatorics - This paper presents a combinatorial construction of low-density parity-check (LDPC) codes from partially balanced incomplete block designs. Since... 相似文献
104.
In this study, thermoluminescence (TL) properties of the biogenic minerals present in the seashell samples at different temperatures and annealing times have been studied. Three explicit peaks are seen in the glow curves roughly at 100°C, 180°C, and 380°C. One of the prominent results is that annealing above 600°C affects enormously the TL intensity, whereas no remarkable TL intensity is observed for unannealed samples. The highest intensity and area under the curve were observed at 700°C annealing temperature, and 180 minutes annealing time and 1500 times bigger than the unannealed samples. A linear dose response is observed between 2.4 and 72?Gy and beyond this value, a sublinear relation is observed. Unfortunately, a huge decrease in TL intensity is observed about 51% of its initial value, after 5 hours of storage time. 相似文献
105.
In this work, four new Nd (III) and Sm (III) complexes of two pentadendate ligands (L1 and L2) were prepared and their molecular structures were determined by single crystal X‐ray diffraction studies. X‐ray analysis showed that the Nd (III) and Sm (III) complexes of L1 sits on a twofold crystallographic axis while the complexes of L2 does not show crystallographically imposed symmetry. Absorption and photoluminescence properties of the complexes were studied both in the solid state and DMF solutions. The fluorescence sensing of nitro‐aromatic compounds [nitrobenzene (NB), 4‐nitrophenol (NP), 2,4‐dinitrophenol (DNP) and 2,4,6‐trinitrophenol (TNP)] were studied by photoluminescence spectroscopy. All four complexes showed better sensitivity towards nitrophenol (NP) with low LOD values. 相似文献
106.
Abdulhadi Baykal Hüseyin Kavas Zehra Durmu? Mine Demir Sinan Kazan Ramazan Topkaya Muhammet S. Toprak 《Central European Journal of Chemistry》2010,8(3):633-638
We report on the synthesis of Mn3O4 nanoparticles (NPs) using a novel sonochemical method without requiring any pH adjustment. Synthesized material was identified
as tetragonal hausmannite crystal structure model of Mn3O4 from XRD analysis. Crystallite size was estimated from x-ray line profile fitting to be 17±5 nm. FTIR analysis revealed stretching
vibrations of metal ions in tetrahedral and octahedral coordination confirming the crystal structure. TEM analysis revealed
a dominantly cubic morphology of NPs with an average size of ∼20 nm. Magnetic evaluation revealed a blocking temperature,
T
B of 40 K above which the material behaves paramagnetic. Asymmetric coercive field is attributed to the interaction between
ferromagnetic Mn3O4 and antiferromagnetic Mn oxide at the surface of nanoparticles.
相似文献
107.
We demonstrate here the rational design of a conformationally flexible C2-symmetric iodosylarene 8g based on secondary n-σ∗ or hydrogen-bonding interactions as a chiral catalyst for the enantioselective Kita oxidative spirolactonization of 1-naphthol derivatives 5. Iodosylarenes 8 were generated in situ from iodoarenes 7 and mCPBA as a co-oxidant. Furthermore, epoxyspirolactone 15 was obtained by the one-pot oxidation of 5 with mCBPA in the presence of 7g. Thus, the enantioselective oxidation of 5 to 6 and the successive enantio- and diastereo-selective oxidation of 5 to 15 proceeded in good yields when we controlled the amount of mCPBA. 相似文献
108.
Carmen Vogt Muhammet S. Toprak Mamoun Muhammed Sophie Laurent Jean-Luc Bridot Robert N. Müller 《Journal of nanoparticle research》2010,12(4):1137-1147
Obtaining small (<50 nm), monodispersed, well-separated, single iron oxide core–silica (SiO2) shell nanoparticles for biomedical applications is still a challenge. Preferably, they are synthesised by inverse microemulsion
method. However, substantial amount of aggregated and multicore core–shell nanoparticles is the undesired outcome of the method.
In this study, we report on the production of less than 50 nm overall size, monodispersed, free of necking, single core iron
oxide–SiO2 shell nanoparticles with tuneable shell thickness by a carefully optimized inverse microemulsion method. The high degree
of control over the process is achieved by understanding the mechanism of core–shell nanoparticles formation. By varying the
reaction time and precursor concentration, the thickness of silica layer on the core nanoparticles can be finely adjusted
from 5 to 13 nm. Residual reactions during the workup were inhibited by a combination of pH control with shock freezing and
ultracentrifuging. These high-quality tuneable core–shell nanocomposite particles exhibit superparamagnetic character and
sufficiently high magnetization with great potential for biomedical applications (e.g. MRI, cell separation and magnetically
driven drug delivery systems) either as-prepared or by additional surface modification for improved biocompatibility. 相似文献
109.
Gorkem Yilmaz Muhammet U. Kahveci Yusuf Yagci 《Macromolecular rapid communications》2011,32(23):1906-1909
Current preparation methods for hydrogels based on redox or photopolymerization of water soluble monomers are simple to use, and flexible, but have the drawback of requiring additional modification steps for tuning or introducing properties for specific purposes. We have devised a simple and rapid synthetic strategy to prepare hydrogels possessing reactive sites to incorporate any molecules of interest by “Click Chemistry”. The strategy is based on the use of propargyl acrylamide (PAm) as comonomer together with acrylamide (AAm) and N,N′‐methylene bisacrylamide (BAAm) as crosslinker in photoinitiated polymerization. With the selective reactivity of photochemically generated free radicals towards acrylic function of PAm, hydrogels with clickable acetylene groups can be prepared in one pot, one step manner. Based on the acetylene functionality, any molecule possessing azide groups can be conjugated onto hydrogel by “Click Chemistry” as demonstrated on the example of fluoroscent azide functional pyrene. 相似文献
110.
Diane Donovan James Lefevre Mary Waterhouse Emine ?ule Yaz?c? 《Annals of Combinatorics》2012,16(3):507-515
A defining set of a t?(v, k, ??) design is a subcollection of its blocks which is contained in a unique t-design with the given parameters. A minimal defining set is a defining set, none of whose proper subcollections is a defining set. The spectrum of minimal defining sets of a design D is the set {|M| | M is a minimal defining set of D}. The unique simple design with parameters ${{t-\left(v, k, \begin{array}{ll}\left(\begin{array}{ll}v-t\\ k-t\end{array}\right)\end{array}\right)}}$ is said to be the full design on v elements. This paper studies the minimal defining sets of full designs when t = 2 and k = 3. The largest known minimal defining set is given. The existence of a continuous section of the spectrum comprising asymptotically 9v 2/50 values is shown. This gives a quadratic length section of continuous spectrum where only a linear section with respect to v was known before. 相似文献