2-nitrophenyl octyl ether

Dioctyl sebacate (DOS) with relative permittivity e of 3.9 and 2-nitrophenyl octyl ether (NPOE) with e = 23.9 are the traditionally used sensor membrane plasticizers. The choice of a plasticizer always depends on a sensor application. Thus, NPOE appears to be more beneficial for divalent ions due to its higher polarity, but for some cases its lipophilicity is insufficient. Furthermore, measurements with NPOE-plasticized sensors in undiluted blood are complicated by precipitation of charged species (mainly proteins) on the sensor surface, which leads to significant potential drifts. Although calcium selectivity against sodium and potassium for NPOE-based membranes is better by two orders of magnitude compared to DOS membranes, the latter are recommended for blood measurements as their lower polarity prevents protein deposition [92],... 

The drug substance has been determined by direct potentiometric titration using chlorpromazine-sensitive electrodes [78. These consisted of an electroactive material in the membrane being either the chlorpromazine complex with either tetraphenylborate or dinonyinaphthalene sulfonate set in a PVC matrix. 2-nitrophenyl octyl ether was used as the plasticizer. 

Acetylcholineesterase Miniaturized multichannel transduc-tor with planar Au electrode which was first covered with a choline-selective liquid membrane made from 66% PVC-polyvinyl acetate (PVA), 33% 2-nitrophenyl octyl ether plasticizer and 1% ion-pair choline phosphotungstate. A second layer of 2% AChE in the PVA-polyethylene dispersion was spread on the top. The electrode was used as working electrode versus Ag/AgCl for potentiometric measurement of Ch and ACh in 0.1 M Tris buffer at 7.4. Optimum pH range for the sensor was 7-9. The calibration graph was linear from 0.02-10 mm ACh and detection limit was 5 pM. Response time was 3-5 min. Sensor was suitable for determination of ACh in biological fluids. [86]... 

Danesi et al. studied the kinetics of transport of Am(lll) from aqueous nitrate solutions to formic acid aqueous solutions using an SLM, which consisted of a solution of a new (carbamoylmethyl)phosphine oxide in diethylbenzene (DEB) [110]. In an attempt to treat simulated low-level radioactive wastewater, Teramoto et al. [Ill] have used an SLM containing CMPO for the uphill transport of Ce(III) from aqueous solution containing a mixmre of nitric acid and sodium nitrate. The simulated waste contained Ce(III), Fe(III), Cr(III), and Ca(II), while the strip solution contained water or sodium citrate solution. Though TBP has been used along with CMPO and w-dodecane as the carrier solution, it also facilitates the transport of HNO3 to the strip side. The acid transport was significantly decreased when CMPO alone in 2-nitrophenyl octyl ether was used as the carrier solution. 

Liq = liquid membrane with ion-exchange solution into the porous diaphgragm PVC = plasticized poly(vinyl chloride) Epoxy = conductive epoxy resin membrane. BA = benzyl alcohol BEHP = bis(2-Ethylhexyl)phthalate DA = 1-decanol DBP = dibutyl phthalate DBS = dibutyl sebacate DNP = dinonyl phthalate DOP = dioctyl phthalate NB = nitrobenzene NPOE = 2-nitrophenyl octyl ether NT = 2-nitrotoluene or 4-nitrotoluene OA = 1-octanol. 

This is analogous to the extraction of sugars with boronic acids described earlier. The recovery of phenylalanine from a fermentation broth has been simplified by using a microporous poly(tetrafluoroethylene) membrane with tri-/j-octylmethylammonium chloride in toluene in the pores.133 Phenylalanine can also be separated using the quaternary ammonium salt with 2-nitrophenyl octyl ether in a cellulose triacetate membrane.134 Kerosene flowing in hollow fiber membranes can remove 99.9% of organic pollutants, such as benzene, p dichlorobenzenc, chloroform, and carbon tetrachloride, from wastewater outside the fibers.135... 

In this work, an ionophore-based solvent polymeric membrane is cast on top of the PEDOT PSS channel in order to obtain an ion-selective organic electrochemical transistor (IS-OECT). The polymeric membrane is composed of 2-nitrophenyl octyl ether (o-NPOE, 57.2% ww), poly(vinyl chloride) (PVC, 27.9% ww), V.. V.. V. . V -i( I i i( ycloli( xyl-3-oxapentanedianii(le (ETH 129, 9.6% ww) and potassium tetrakis(4-chlorophenyl)borate (KTpCIPB, 5.4% ww), where ETH 129 is a Ca2+-selective ionophore. The channel region of the transistor that is coated by the Ca2+-selective membrane is immersed in an aqueous solution containing 0.1 M KC1 as a background electrolyte and... 

The first report of MALDl on polystyrene samples is the seminal paper by Bahr et al., where the matrix used was 2-nitrophenyl octyl ether, which is a liquid. Liquid matrices can be best used with instruments equipped with horizontal sample plates. In the case of vertical plates, the thickness of the matrix layer at a specific spot on the probe tip varies with time (due to gravity). 

Chen, J., Boerrigter, H., Veltkamp, A.C., Technetium(VII) transport across supported liquid membranes (SLMs) containing 2-nitrophenyl octyl ether (NPOE), Radiochim. Acta 89, 523, 2001. 

A recent report with improved solvent containing 0.01 M DTBCH18C6 in 20% 1-octanol + 80% toluene has yielded rapid Sr(II) transport initially that was subsequently overwhelmed by large acid cotransport resulting in Sr(ll) back transport [75]. Recently, near quantitative transport of Sr(ll) from 3 M HNOj solution has been reported using the crown ether in 2-nitrophenyl-octyl ether (2-NPOE) and n-dodecane mixture [80]. The flux, however, was low that necessitated the use of HFSLM technique to increase the throughput for possible application on large scale. 

The silsesquioxane mixtures or the separated silsesquioxanes can be analyzed by MALDl-TOF-MS (Table 2). MALDI-TOF mass spectrometry was carried out on a Kratos Kompact MALDI 111. 0.5 pL of a solution (25 mg/mL) of 2,4,6-trihydroxyacetophenone or 20 mg/mL of 2-nitrophenyl octyl ether and 10 mg/mL silver trifluoroacetate were mixed on a stainless steel sample slide. The solvent was evaporated in a stream of air at ambient temperature. Bovine insulin was used for calibration. Conditions for the measurements polarity positive, flight path reflection, 20 kV acceleration voltage, nitrogen laser (A = 337 nm). 

Nitrophenyl octyl ether is a liquid matrix. It was employed in the very first set of MALDI experiments. Liquid matrices can be used with instruments equipped with TOP analyzers and these can be arranged horizontally or vertically. However, in the case of horizontal analyzers, the thickness of the matrix layer in a specific spot varies with time (due to gravity). This causes continuous variations of the MALDI conditions. 

Organic solution Carrier 10-2 M in 2-nitrophenyl octyl ether. Source Adapted from Z. Asfari et al.," p. 382. 

Amperometric SPE (10% PVC, 3% tetra butyl ammonium hexafluoro-phosphate, 87% 2-nitrophenyl octyl ether) Sensitivity is 277 nA/ppm, reeovery time is 19 s... 

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