Topic
Liquid paraffin
About: Liquid paraffin is a research topic. Over the lifetime, 6185 publications have been published within this topic receiving 52956 citations.
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TL;DR: By using liquid paraffin and antifoam, both the epoxidation activity and the stability were improved, especially for the P‐1‐200 strain, over that for nonimmobilized cells, and N. corallina cells showed an apparent preference for a hydrophobic, as compared to a hydrophic, environment.
Abstract: Nocardia corallina B276 cells were immobilized by emulsification with liquid paraffin and an antifoam agent at room temperature. The immobilized cells were studied for their ability to carry out the formation of propylene oxide from propylene and oxygen. The evaluations were done with the cells in a bubble-type reactor with a continuous gas feed of 5% propylene and 11.6-95% oxygen, with the balance nitrogen. By using liquid paraffin and antifoam, both the epoxidation activity and the stability were improved, especially for the P-1-200 strain, over that for nonimmobilized cells. The N. corallina cells showed an apparent preference for a hydrophobic, as compared to a hydrophilic, environment. The propylene-oxide-forming activity of the immobilized cells was higher at 40 than at 30 degrees C reactor temperature and with 20% (versus 95%) oxygen in the feed. The stability was markedly better at 30 degrees C and with 20% oxygen. High gas flowrates gave increased apparent activity probably because of less resistance to substrate mass transfer. The effects of pH were minor. The role of glucose as the energy source for regeneration of cofactors for the monooxygenase system also is discussed.
14 citations
TL;DR: Proton magnetic resonance of liquid paraffin has been observed in a magnetic field of 270 oersted rotating at 25 kHz in this article, where the magnetic resonance was observed in the case of a single-input single-out (SISO) system.
14 citations
TL;DR: In this article, the behavior of compounds with different polarity on untreated thin layers of silica gel or cellulose, and on layers impregnated with liquid paraffin or 1-octanol, was studied.
14 citations
01 Jan 2000-Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment
TL;DR: The model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, and their subsequent steady- state permeation rates.
Abstract: Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.
14 citations
TL;DR: A method based on soft templates for pH sensitive microcapsule fabrication was developed using a layer-by-layer assembly technique in this paper, where Toluene-in-water emulsion droplets were first stabilized by a surfactant sodium dodecyl benzene sulfonate (SDBS), modified latex beads were then adsorbed onto the droplet surfaces to make the emulsion more rigid.
Abstract: A method based on soft templates for pH sensitive microcapsule fabrication was developed using a layer-by-layer assembly technique. Toluene-in-water emulsion droplets were first stabilized by a surfactant sodium dodecyl benzene sulfonate (SDBS). Poly(diallyldimethyl ammonium chloride) modified latex beads were then adsorbed onto the droplet surfaces to make the emulsion more rigid. PSS (poly(sodium 4-styrenesulfonate))/PDDA (poly(diallyldimethyl ammonium chloride)) was assembled alternately onto the emulsion surface to form the microcapsules. Zeta potential analyzer, scanning electron microscopy (SEM), transmission electron microscopy (TEM), FT-IR, and fluorescence microscopy were used to characterize the samples. The toluene droplet templates were removed by ethanol upon heating. Fluorescein, as the water-soluble model drug, was loaded into the microcapsules. Its release behaviors were investigated as a function of wall thickness and pH. The maximum release percentage 61% was obtained after 36 hours at 37 °C at pH 7 with one double layer capsule. The capsule itself is nontoxic, while 5-fluorouracil (5-FU) loaded capsules killed 64.18% SK-RC-2 cells at a concentration of 17 μM at pH 7, which shows the great potential of this type of microcapsule in cancer chemotherapy. Olive oil and liquid paraffin were used to replace the toluene for forming soft templates in order to obtain microcapsules which are suitable for loading hydrophobic drugs. Sudan-1 was chosen as a hydrophobic model drug and 25% release was obtained after 36 hours at 37 °C.
14 citations