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Nanostructured Drug Delivery of Nutraceuticals for Counteracting Oxidative Stress
Published in Bhupinder Singh, Minna Hakkarainen, Kamalinder K. Singh, NanoNutraceuticals, 2019
Shobhit Kumar, Bharti Gaba, Jasjeet K. Narang, Javed Ali, Sanjula Baboota
Controlled release systems become attractive strategy to obtain drug action for an extended period of time. Xie et al. (2013) developed silymarin monolithic osmotic tablets by compressing solid dispersion of drug. The tablets were composed of cellulose acetate coating, which acted as a semipermeable membrane. In 20 h, the tablets showed zero-order release, which indicated that the formulation was capable of releasing the drug in a controlled manner and provided prolonged availability of the drug in the body.
Electrochemical Composition Measurement
Published in John G. Webster, Halit Eren, Measurement, Instrumentation, and Sensors Handbook, 2017
Michael J. Schöning, Arshak Poghossian, Olaf Glück, Marion Thust
Such pH changes are detected by the ISE, in this case by a pH-sensitive glass electrode. Semipermeable membrane materials are polytetrafluoroethylene, polypropylene, or silicone rubber. The internal solution contains sodium chloride and an electrolyte with the corresponding ion that is determined. Gas-sensing electrodes have been realized for gases dissolved in solution, such as NH3, NH4Cl, CO2, H2CO3, NaHCO3, NO2, NaNO2, SO2, H2SO3, K2S2O5, CN, SCN, Cl2, Br2, I2, and H2S.
Osmotic pressure estimation using the Pitzer equation for forward osmosis modelling
Published in Environmental Technology, 2020
M. Khraisheh, N. Dawas, M.S. Nasser, M.J. Al-Marri, Muataz A. Hussien, S. Adham, G. McKay
The stress on water resources to match the ever-growing demand for water is very well documented in the literature due to population growth, increased industrial activities and climate change. Desalination, a general term used for processes that removes salts from water, is used extensively around the globe for the purpose of increasing the production of high-quality water, with reverse osmosis and multi stage flash evaporation (MSF) being the two most widely used technologies [1,2]. In RO, hydraulic pressure is applied to push the water across a semipermeable membrane; a process associated with reported high energy requirements, membrane fouling and other costs linked with operations and pretreatment, making the need for more energy-efficient membrane processes an important area of focus for researchers [3,4]. Compared to thermal and RO separation processes, many researchers now view FO as a low energy alternative technology, that also offers minimal chemical discharges and low hydraulic pressure and temperature requirements. Linares et al. [2] presented an extended review regarding the recent niches in seawater desalination. In this review, it was reported that the main reason behind the low energy requirement in FO stems from the fact that this process is based on mimicking naturally occurring phenomena: osmosis; a process omnipresent in all living biological cells with almost no external hydraulic pressure requirements. In FO systems, a solution with higher concentration than the feed solution (termed ‘draw’ solution) is utilized to create a concentration variance that drives pure water through the semipermeable membrane. The semipermeable membrane permits molecules of water only to pass through the membrane while rejecting the salts present in the solute. Intensive research has been taking place to assess the suitability of many materials in the role of forward osmosis membranes [5–8]. The draw solution (DS), based on its intended end use, may be treated or diluted and in which case, the treatment process energy requirements should also be taken into account. In addition to its applications in seawater and brackish water desalination, recent reports employed FO with biological wastewater treatment especially those associated with osmotic membrane bioreactors [1,9–11].