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In this study, liver-directed gene transfer in rats with calcium phosphate (CaP) nanoparticles and the effect of the route of administration and surgical manipulations on transfection efficiency is reported. Formulations of CaP nanoparticles entrapping plasmid DNA (pDNA) were prepared by the reverse micellar method using two different surfactants. Transmission electron microscopy, scanning electron microscopy and dynamic light scattering were used to characterize the CaP–DNA nanocomposites. The morphological characteristics of the formulations showed a strong dependency on temperature. Gel electrophoresis experiments indicated that there was no degradation of the encapsulated pDNA, and in vitro cell transfection in HEK-293 and primary hepatocytes from rats as well as in vivo intraductal delivery experiments suggested that CaP nanoparticles led to significant and prolonged transgene expression. Therefore, our methodology gives a stable and viable formulation for hepatic gene therapy. Low-DNA dosage entrapped in CaP nanoparticles makes it an effective gene delivery system for clinical applications. [ABSTRACT FROM AUTHOR]

A significant quantity of hydrocarbons remains in the reservoir after production using primary and secondary techniques. Traditional recovery techniques produce about 33 % of the original oil in place. However, the utilization of chemicals such as surfactants and polymers facilitate the additional recovery of one‐third of this oil. Researchers are currently aiming at mixing surfactant and nanoparticles for their potential applications in petroleum industry. In this work, authors claimed to be the first to study usage of synthesized Mesoporous Silica Nanoparticles (MSN) with Sodium Dodecyl Sulphate (SDS) surfactant to understand its applicability in Chemical Enhanced Oil Recovery through evaluation of the surface tension & Interfacial tension, surfactant adsorption, contact angle, and core flooding experiments. Surface tension studies revealed a synergistic interaction between MSN and anionic surfactant molecules. With the introduction of 2500 ppm of anionic surfactant, the surface tension of deionized water reduces to 34.5 mN/m from 72.4 mN/m. The surface tension of the mixture was further lowered by ∼9.8 % with the addition of 300 ppm MSN. The Interfacial Tension results also showed the same trend. When 300 ppm of MSN was introduced, then IFT values decreases from 8.13 mN/m to 3.91 mN/m at 2500 ppm of anionic surfactant. Contact angle measurements after MSN injection went from 77.98° for SDS (2500 ppm) to 73.36°, 66.54°, and 41.95° for 100, 200, and 300 ppm of MSN, respectively. This demonstrates that the shift toward water‐wet behavior increased along with the MSN concentration. Additionally, adding 300 ppm of MSN lowered surfactant adsorption by ∼80 % at a surfactant concentration of 2500 ppm. Up to 72.27 % of the OOIP could be recovered using the chemical slug made of SDS surfactant, polymer, and MSN. The research data suggests that the MSN can increase the effectiveness of the chemical injection approach, which can be used to recover more oil. [ABSTRACT FROM AUTHOR]

Surfactant flooding is a prolific enhanced oil recovery technique. It alters the rock fluid interfacial interactions between reservoir fluids and rocks. However, a pair of impeding factors often limit the economic viability of the process and need to be optimized. The first is the surfactant loss on the adsorbent surface due to adsorption making it a potential environmental problem. The second is the Critical Micelle Concentration (CMC) which governs the amount of surfactant pumped. This study aimed to minimize the surfactant loss and the CMC, thereby optimizing the flooding efficiency and reducing the environmental concerns for nanoparticle applications. To achieve this, Silicon Carbide nanoparticles (SCN) were employed as additives to the surfactant solution. It was observed that the use of SCN reduces the surfactant adsorption by as much as 44 % and the critical micelle concentration by 14 %. The studies also observed that the concentration of SCN required to get these results is dramatically (more than 25 times) lower than previously reported literature on other nanoparticles. To adsorption isotherm studies provide an insight into the type of adsorption taking place. The adsorption isotherm follows the Langmuir model. [ABSTRACT FROM AUTHOR]