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101.
Many human diseases occur due to the over or under-expression of genes which can be corrected either by silencing or over-expression, respectively by transforming with specific nucleic acid (NA). NA transformation for medical purposes to alter the cellular gene expression is challenging because NA cannot cross efficiently the cellular biomembrane. One option, the viral vectors, is risky for patients and, the non-viral vectors have lower transformation efficiency. From the past few years, nanoparticles (NPs) are being studied extensively for their use as a vector to deliver NA. They are of a sub-micron size, have a large surface area, rapid absorption ability and can reach inside of the cells. These properties make them a suitable gene carrier. NPs types - organic, inorganic, organic/inorganic hybrid and polymeric NPs, having different properties that can be used to deliver the NA. They possess various properties like biocompatibility, targeted delivery of gene, controlled release of NA which makes them suitable for different uses. In this review, we are describing and comparing various methods to synthesize various kinds of NPs and how they can be conjugated with NA. A series of modifications in NPs to form the polyplex are also discussed along with the varying outcomes in terms of changes in the gene expression and its cytotoxicity towards different cell lines. This review is helpful for nano-scientists to decide which method to be followed for a specific need via controlling gene expression. 相似文献
102.
Synthesis and surface engineering of magnetic nanoparticles for environmental cleanup and pesticide residue analysis: A review
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Ranjeet Kaur Abshar Hasan Nusrat Iqbal Samsul Alam Mahesh Kr Saini Syed Kalbe Raza 《Journal of separation science》2014,37(14):1805-1825
In recent years, water pollution and pesticide accumulation in the food chain have become a serious environmental and health hazard problem. Direct determination of these contaminants is a difficult task due to their low concentration level and the matrix interferences. Therefore, an efficient separation and preconcentration procedure is often required prior to the analysis. With the advancement in nanotechnology, various types of magnetic core–shell nanoparticles have successfully been synthesized and received considerable attention as sorbents for decontamination of diverse matrices. Magnetic core–shell nanoparticles with surface modifications have the advantages of large surface‐area‐to‐volume ratio, high number of surface active sites, no secondary pollutant, and high magnetic properties. Due to their physicochemical properties, surface‐modified magnetic core–shell nanoparticles exhibit high adsorption efficiency, high rate of removal of contaminants, and easy as well as rapid separation of adsorbent from solution via external magnetic field. Such facile separation is essential to improve the operation efficiency. In addition, reuse of nanoparticles would substantially reduce the treatment cost. In this review article, we have attempted to summarize recent studies that address the preconcentration methods of pesticide residue analysis and removal of toxic contaminants from aquatic systems using magnetic core–shell nanoparticles as adsorbents. 相似文献
103.
Anil Saini Suresh 《合成通讯》2013,43(21):3655-3661
α-Amino nitriles are synthesized in a one-pot, three-component coupling of aldehydes, amines, and trimethylsilyl cyanide using a catalytic amount of LiBr at ambient temperature. 相似文献
104.
K. K. Saini C. P. Sharma Chander Kant D. K. Suri Subhas Chandra
S. P. Tiwari
《Physica C: Superconductivity and its Applications》1993,210(3-4):502-508Samples with nominal composition Tl2Ba2Cu1.2 (copper-rich Tl-2201) were calcined at various temperature, i.e. from 865 °C to 910°C and for various durations (10–20 h). The samples were sintered for 31/2 min at various temperatures. The X-ray powder diffraction pattern indicates that most of the Tl-Ba-Cu samples (Tl-2201) are single-phase materials. All the lines in the X-ray pattern are indexable on a tetragonal unit cell showing tetragonal symmetry having space group 14/mmm with a=3.86 Å C=23.11 ± 0.06 Å as unit cell parameters. R−T and AC susceptibility measurements show Tonc, from 90 to 104 K. There is an elongation of the c-axis (c=23.24 Å) for the sample showing the highest Tc. Wet chemical analysis confirms the deficiency of thallium. This suggests some substitution of Cu in place of thallium which leads to an increase in the average oxidation state of copper, responsible for the creation of holes (charge carriers). 相似文献
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Li Z Xu Y Ma X Dervishi E Saini V Biris AR Lupu D Biris AS 《Chemical communications (Cambridge, England)》2008,(28):3260-3262
We report on the role of CO(2) in improving carbon nanotube yield and crystallinity from catalytic chemical vapor deposition of hydrocarbons. 相似文献
109.
Romesh Kumar Kulbir Singh Heera Saini Sanjay Kumar 《Advances in Applied Clifford Algebras》2016,26(1):217-235
In this paper we study the bicomplex version of weighted Hardy spaces. Further, we describe reproducing kernels for the bicomplex weighted Hardy spaces. In particular, we generalize some results which holds for the classical weighted Hardy spaces. We also introduce the notion of bicomplex C*-algebra and discuss some of its properties. 相似文献
110.
Balwinder Saini Ashwani Kumar Ruby Rani Rajinder K. Bamezai 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(7):1350-1361
The density, viscosity and speed of sound of pure p-anisaldehyde and some alkanols, for example, methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, butan-2-ol, 2-methylpropan-1-ol, and the binary mixtures of p-anisaldehyde with these alkanols were measured over the entire composition range at 303.15 K. From the experimental data, various thermodynamic parameters such as excess molar volume (VE), excess Gibbs free energy of activation (ΔG*E), and deviation parameters like viscosity (Δη), speed of sound (Δu), isentropic compressibility (Δκs), are calculated. The excess as well as deviation parameters are fitted to Redlich—Kister equation. Additionally, the viscosity data for the systems has been used to correlate the application of empirical relation given by Grunberg and Nissan, Katti and Chaudhari, and Hind et al. The results are discussed in terms of specific interactions present in the mixtures. 相似文献