Ml Of Chloroform Research Articles

The Determination of Anionic Surfactants in Water by an Azure A Method

Abstract Various methods for the analysis of anionic surfactants (such as LAS and ABS) in aqueous solution were reviewed, evaluated, and/or assessed. Emphasis was placed on the development of field test kits based on a modified colorimetric method involving the use of Azure A. The simplified and improved Azure A Method requires only 6 ml of aqueous reagent and 25 ml of chloroform for analyzing one sample. The principles, analytical procedures and limitations of the method are described in detail. A field test kit based on the use of a portable spectrophotometer (or photometer), is proposed for use by the personnel with limited training in chemistry.

The Differential Elution of Drugs from XAD-2 Resin

Biological fluids and tissue extracts prepared according to a previously published method were passed through a column of Amberlite XAD-2 resin for removal of drugs. The differential elution of the adsorbed drugs from the resin was performed by sequential elution of the drugs in four steps. The column was first washed with 30 ml of 0.05M sodium acetate buffer, pH 4.55. Drugs exhibiting acidic or neutral characteristics were then eluted from the column with 100 ml of chloroform in 20-ml aliquots. The column was then washed with 30 ml of 0.1M potassium carbonate, which was discarded. Drugs exhibiting basic characteristics were then eluted from the column with 100 ml of chloroform:isopropanol (3:1) in 20-ml aliquots. Sensitivity of drug detection with this method by thin-layer chromatography was 0.5 mug/ml in a 10-ml sample for nearly all drugs tested.

Spectrophotometric determination of micro amounts of tin(IV) with zephiramine

The thiocyanate complex of tin(IV) reacts with zephiramine to give a white precipitate. The precipitate, extracted into chloroform, has an absorption maximum at 273 nm. The molar absorbancy is about 7500 at 273 nm and is stable for at least 5 hours.The composition for the extracted species is assumed to be 1:4 (Sn:zephiramine) by the continuous variation study. Extraction was carried out with 10 ml of chloroform from 25 ml of the aqueous sample solution. Beer's law holds for the concentration of 5.0×10-6 M to 5.0×10-5 M in the aqueous phase. Micro amounts of tin(IV) can be determined by this method. The effects of diverse ions were investigated, and its result was shown in Table I. Many ions except mercury, copper, iron, cobalt, palladium, platinum, ruthenium, iodate, periodate, vanadate, molybdate and tungstate, do not interfere with the determination when their amounts are equal to that of tin (IV).

The Lipid Composition of a Species of Alternaria of the “Alternaria Alternata Group”

(1973). The Lipid Composition of a Species of Alternaria of the “Alternaria Alternata Group”. Mycologia: Vol. 65, No. 4, pp. 958-963.

Extraction-photometric determination of molybdenum in zirconium-, nickel- and iron-base alloys using oxine

An extraction-photometric method for the determination of molybdenum in zirconium-, nickel- and iron-base alloys was established. One gram of zirconium-base alloys is dissolved in 10 ml each of sulfuric acid and 50% ammonium sulfate solution by heating. Molybdenum oxinate is formed by adjusting the pH to 0.851.2 in the presence of 10 ml of 5% oxine solution. The oxinate is extracted by shaking vigorously for 1 min. with 10 ml of chloroform. The chloroform solution is washed by shaking for 1 min. with 50 ml of 0.1 M oxalic acid solution. After the drying of the solution with anhydrous sodium sulfate, the absorbance is measured at 380 nm.Nickel- and iron-base alloys are dissolved in the mixed acid (nitric acid : hydrochloric acid : water = 1 : 1 : 1) by heating. The formation and extraction of the oxinate is carried out by the same way as described above except for analyzing a sample containing more than 0.01 g of iron. One gram of iron can be masked by addition of 2 g of ascorbic acid and adjusting the pH to 1.52.0. Less than 0.5 mg of tungsten is masked by addition of 0.2 g of fluoride ion before the extraction. According to this method, molybdenum in these alloys can be determined rapidly below the order of a few ppm.

Analysis of metals by solid-liquid separation after liquid-liquid extraction spectrophotometric determination of palladium(II) by extraction of palladium dimethylglyoximate with melted naphthalene

A method of liquid-liquid extraction of palladium di-methylglyoximate with molten naphthalene followed by solid-liquid separation is successfully applied to palladium. The complex between palladium and dimethylglyoxime is easily extracted into molten naphthalene. After extraction, the very fine solidified naphthalene crystals are dissolved in chloroform, and the absorbance of the resultant solution is measured at 370 nm against a reagent blank. Beer's law is obeyed for 30–370 μg of palladium in 10 ml of chloroform, and the molar absorptivity is calculated to be 1.72 × 10 4 l.mole. −1mm −1. Various alkali metal salts and metal ions do not interfere. The interference of nickel(II) is overcome by the extraction at pH 2, and that of iron(III) by masking with EDTA or by reduction to iron(II). The method is rapid and accurate.

Isolation of a proteolipid from spleen capsule binding [formula omitted

Bovine spleen capsules were extracted with chloroform-methanol (2:1, v/v) and the proteolipids were separated by column chromatography on Sephadex LH-20. Five proteolipid peaks were eluted with chloroform and one peak with chloroform-methanol (4:1, v/v). Only Peak 1 eluted between 17–22 ml of chloroform showed binding for [ 3H]norepinephrine. The saturation curve of the binding in Peak 1 suggests that this proteolipid contains two groups of sites with different dissociation constants. For 200 000 g of proteolipid 3 moles of norepinephrine are bound with high affinity and about 27 moles with low affinity. Similar findings were obtained using a partition method for the study of the binding and the competition with some adrenergic antagonists was demonstrated. The possibility that Peak 1 of proteolipid represents the adrenergic receptor of the spleen capsule is discussed.

Effect of bases on the analysis of arsenic with silver diethyldithiocarbamate

A small amount of arsenic has been determined colorimetrically by using silver diethyldithiocarbamate in pyridine (Ag-DDTC method). On the other hand, H. Bode reported that a similar reaction also occured in Ag-DDTC chloroform solution by an addition of several solid organic bases such as ephedrine. Recently, S. Nakao et al. obtained a good result by an addition of dimethylformamide.In this paper, 24 kinds of liquid organic bases were examined. This method based on the fact that AsH3 reacts with Ag-DDTC in chloroform containing the bases, and the light absorption and the calibration curve of colored products were examined.The amount of Ag-DDTC and of organic bases in the samples were 1.03×10-4 mole and 3×10-2 mole in 10ml of chloroform solution, respectively. However, in the case of triethylamine, 0.26×10-4 mole of Ag-DDTC in 10ml of chloroform was enough for this purpose. It was concluded from the results that the bases which give an absorption in the visible region to the solution are triethylamine, 2, 4-lutidine, 2, 6-lutidine, α-picoline, β-picoline and γ-picoline. The calibration curves obeyed Beer's law in the concentration range from 1 to 25ppm.Among these bases, triethylamine gave the best results, namely, in the case of triethylamine, the amount of Ag-DDTC necessary was quarter of other cases. Therefore the authors concluded that triethylamine, which has less offensive smell and is cheaper than pyridine, can be used for the determination of arsenic with Ag-DDTC instead of pyridine.

Analysis of Sulfonate and Sulfate Type Surfactants

A rapid micro procedure for the determination of sulfonate and sulfate type surfactants was developed by modification of the methylene blue titration method. The method is based on the oxidation of methylene blue chloride to dimethylthionoline, a red dye, in the presence of chloroform and sodium hydroxide.In a typical procedure 5 ml of sample solution (0.5-4 mmolg) is pipetted into titration bottle. To the sample solution are added 1 ml of methylene blue solution as the indicator and 10 ml of chloroform after adjustment of pH at 11-12 with 0.5 N sodium hydroxide. The solution is titrated with cationic standard solution. The end point is reached when the chloroform layer turns clear red.The results show that the anionic active component of various amphoterics (taurine type, sunfonate betain type, sulfate imidazoline type) and various anionics can be determined rapidly and with accuracy (deviation 71%) by this method. But carboxylic acid type amphoterics and soap can not be determined accurately.

Sampling and determination by ultraviolet absorption of oil mists and solvent vapors.

Oil mist can be efficiently collected on filter paper or by an electrostatic precipitator. Samples containing 0.05 mg of oil can be accurately determined by ultraviolet spectrophotometry. Gross amounts of sample contaminants, such as soil, water, and pipe scale, can be tolerated without appreciable loss in accuracy. Petroleum distillate vapor is efficiently collected on silica gel or in a midget bubbler containing chloroform. Maximum collection efficiency is achieved at sampling rates not exceeding 100 cc/min. Samples containing as little as 0.5 mg in 10 ml of chloroform or ethanol may be determined by spectrophotometry. With both oil and petroleum distillate determinations, it is necessary to obtain a sample of the particular product in question in order to construct a standard spectrophotometric curve.

Carrier-free separation of228Ac from aged thorium nitrate

Reagents: Unless stated otherwise, all reagents used were of analytical grade. The reagents required are: fuming nitric acid, barium nitrate (a carrier), cupferron (5% aqueous solution), chloroform, aqueous ammonia, ammonium acetate (a buffer), lead nitrate (a carrier), hydrogen sulphide, and dithizone (for the detection of lead). Apparatus: Separatory funnels, beakers, laboratory centrifuge, flask shaker, Kipp's apparatus, and GM beta-counting equipment. Procedure: 1. Dissolve 5 g of thorium nitrate in 60-70 % nitric acid. Add 5 mg of barium carrier as a barium nitrate solution (5 mg/ml). 2. Precipitate barium(radium) nitrate with fuming nitric acid, adding a little at a time followed by vigorous stirring. The reaction vessel should be kept immersed in crushed ice. Separate the precipitate by centrifugation, and dissolve in a very small quantity of distilled water. Set aside for a couple of days to let 22SAc grow in. 3. Treat the acid barium(radium) nitrate solution with 3 ml of a 5 % aqueous solution of cupferron and 5 ml of chloroform. Shake mechanically for 5 10 min. Separate the organic phase containing thorium and discard it. 4. Adjust the pH of the aqueous phase to 6 with aqueous ammonia. Add 10 ml of 0.9M ammonium acetate, shake, add 3 ml of aqueous cupferron (5 % solution)

Extraction and spectrophotometric determination of tungsten in ferro-niobium with TPAC-thiocyanate complexes

One fifth gram of a sample was fused with potassium pyrosulfite and taken up with 50 ml of hydrochloric acid (1+2) containing 2 g of ammonium oxalate. It was diluted to 100 ml with water. To a 10 ml aliquot corresponding to ca. 100 μg of W were added 20 ml of hydrochloric acid and 5 ml of stannous chloride solution (20 w/v% in hydrochloric acid), and the mixture was boiled gently for about 2 min. to reduce tungsten. After cooling, it was transferred by washing with hydrochloric acid to a 200 ml polyethylene separatory funnel, and 5 ml of ammonium hydrogen fluoride solution (20 w/v%) was added as a masking agent for niobium. Each 3 ml of TPAC solution (0.025M) and sodium thiocyanate solution (15 w/v%) was added and shaken well. It was made up to 70 ml with hydrochloric acid and shaken vigorously with accurately 20 ml of chloroform for 2 min. The separated layer of chloroform was filtered through a dried paper, and the amount of tungsten was obtained by measuring absorbance at about 400 mμ. The method was successfully applied to the determination of about 0.5% of tungsten as an impurity in ferro-niobium.

Spectrophotometric determination of phenylephrine hydrochloride in pharmaceutical preparations

Phenylephrine HCl (I) reacts with 4-aminoantipyrine and K3Fe(CN)6 in an alkaline medium buffered at pH 9 to give orange coloration. The chromogen produced extracted into chloroform gives an absorption maximum at 460 mμ.A new spectrophotometric method based on this color reaction has been established for the determination of (I) in pharmaceutical preparations.Influences of 45 compounds on the determination were examined, whereby those by sulpyrine, aminopyrine, isopropylantipyrine, acetaminophen, ethoxybenzamide, salicylate, theophylline, quinine HCl, ascorbic acid, taurine, etc. are eliminated by the extraction with chloroform in acidic medium.The procedure recommended is as follows. A sample {containing 50 mg of (I)} is taken in a separatory funnel. Ten milliliters of water and 10 ml of 0.1 N HCl are added, and interfering substances is extracted 3 times with 30 ml portions of chloroform. The aqueous solution is transfered into a 50 ml volometric flask and is diluted exactly to 50 ml with water. A 2 ml aliquot is taken into another 50 ml volumetric flask and made up to the mark with water. Two milliliters of this solution is transfered to a 25 ml glass-stoppered test tube, and 10 ml of 0.2 M borate buffer, 2 ml of 1% 4-aminoantipyrine solution, and 2 ml of 2% K3Fe (CN) 6 solution are added. After allowing to stand for 5 min., it is shaken with 10 ml of chloroform for 1 min. The separated chloroform layer is dried by shaking with 2 g of Na2SO4, and the absorbance is measured at 460 mμ (ET) against chloroform. At the same time, the absorbance of the standard solution (Es) is determined, and the amount of (I) is calculated by ET/ES.

外見上健康なマウスからの抗酸菌の検出

Nishimura and associates have reported that not only healthy mice but also non-leprous human skin are considerably contaminated with acid-fast bacillus, but as yet, there has been little information on such findings. Nishimura's observations have caused a non-neglectable problem in the conduction of experiments in which experimental animals are inoculated with leprosy or murine leprosy bacillus; and also in bacteriological examination of leprosy patients. Further investigations seemed justified and this study was undertaken to evaluate whether, and to what extent, healthy mouse could be infected with acid-fast bacillus. Four groups of mice were used. Group A consisted of 21 CF#1 mice born and raised in an animal room used for mycobacterial-infected animals; Group B of 58 CF#1 mice born and allowed to remain, until the date of autopsy, with mice infected with murine leprosy; Group C of 25 dd-hybrid mice obtained from an unspecified source; and Group D of 46 CF#1 mice bred at random and raised under careful control in a room unrelated to mycobacterial-infected animals. For examination of acid-fast bacillus, foot-pad, dorsal skin, lung, liver, spleen and kidney were selected. These tissues were minced and ground with 2ml of a 1 per cent sodium hydroxide solution. The tissue suspension was transferred to a small test tube and left to stand for 30 minutes to allow settling of the heavy tissue elements. Oneml of the supernatant was decanted into a centrifuge tube, shaken with 0.1 ml of chloroform for 3 minutes, and centrifuged at 1, 000×g for 10 minutes. The chloroform button was placed on a spot-plate and stamped on a slide glass with a small glass rod. The slide was stained by carbol-fuchsin and Toda's solution. For each specimen, 200 oil-immersion fields were carefully examined for acid-fast bacillus. As shown in the Table 1, acid-fast bacilli were detected in one of 21 mice in Group A, 9 of 58 in Group B, and none in Group C and D. Abundant bacilli were found in only one mouse in Group B. These results are not in agreement with Nishimura's reports. On the basis of our observation, it seems unlikely that acid-fast bacillus would be found so frequently in normal mice.

Spectrophotometric determination of salicylamide in pharmaceutical preparations

Salicylamide (I) reacts with dimethyl-p-phenylenediamine, and K3Fe (CN)6 in an alkaline medium (phosphate buffer : pH 8.0) to give green coloration (indophenol dye). This chromogen produced is extractable with chloroform, the extract showing an absorption maximum at 650mμ.A new spectrophotometric method, based on this color reaction, has been established to the determination of (I) in pharmaceutical preparations.Influences of 47 compounds were examined. The interferences from acetaminophene, ethoxybenzamide, salicylate, phenylephrine hydrochloride, sulpyrine, ascorbic acid, etc. are eliminated by the extraction with chloroform in an acidic medium. The recommended procedure is as follows. Sample {containing 100mg of (I)} is taken in a separatory funnel. To it are added 10ml of water and 10ml of 0.1 N HCl, and it is extracted 4 times with 30ml portions of chloroform. The extracts are combined and evaporated on a water bath. The residue is dissolved in 50ml of ethanol, and is made up exactly to 100ml with water. A 10ml aliquot is taken into another 100ml volumetric flask, and is made up to 100ml with ethanol. Ten ml of this solution is taken into another 100ml volumetric flask and prepared in the similar way.A 2 ml aliquot is transfered into a 30ml glass-stop-pered test tube. Five milliliters of buffer solution (phosphate buffer : pH 8.0), 2ml of 0.05% dimethyl-p-phenylenediamine solution and 1 ml of 1% K3Fe(CN)6 solution are added. After 5 min., the solution is shaken with 10ml of chloroform. The separated chloroform layer is dried with 2 g of Na2SO4, and is filtered. The absorbance is measured at 650mμ (ET) against chloroform. At the same time the absorbance of standard solution (ES) is determined, and the amount of (I) is calculated by ET/ES.

Structure of a lipid intermediate in cell wall peptidoglycan synthesis: a derivative of a C55 isoprenoid alcohol.

The peptidoglycani of bacterial cell walls is synthesized in a reaction mechanism in which a membrane-bound lipid serves as a carrier for the sugars and amino acids that eventually become part of the peptidoglycan.1 One intermediate in the reaction cycle is represented as lipid-P-P-disaccharide-pentapeptide. This intermediate is common to a number of different bacteria. However, its disaccharidepentapeptide moiety (GlcNAc-M\/urNAc-L-ala-D-glu-L-lys-D-ala-D-ala)2 becomes modified in various ways in different organisms.3 The modified disaccharidepeptide moiety is then transferred to an endogenous acceptor with introduction of a new unit into a growing peptidoglycan. The purpose of the present paper is to report that lipid-P-P-disaccharide-pentapeptide has been obtained in a highly purified form from Mlicrococcus lysodeikticus, and that the nature of the lipid moiety of this intermediate has beeln elucidated. Soon after the discovery of the occurrence of a lipid intermediate in peptidoglyean synthesis, a lipid carrier in the biosynthesis of the lipopolysaccharide of the cell wall of Salmonella was described.4' The structure of this substance is reported in a paper by Wright et al.6 Isolation of Lipid-P-P-Disaccharide-Pentapeptide fromn M. iysodeikticus. Largescale preparation of the lipid intermediate was carried out using techniques essentially the same as those described previously.7 Particulate enzyme was prepared after lysozyme lysis of cells of 111. lysodeilticus8 and incubated with the uridine nucleotide substrates to generate the lipid intermediate. The incubation mixture contained 1000 ml of particulate enzyme prepared in 0.05 111 Tris-HCl buffer, pH 7.4, and 0.01 M M\4gCl2, 1.7 ml of 12 mM\4 UDP-1\'furNAc-pentapeptide (containing 8.7 X 106 cpm of C'4-lysine),9 8 ml of 10 mM\4 UDP-GlcNAc and 30 ml of 5 per cent deoxycholate. Enzyme prepared after lysozyme lysis of cells of M. lysodeikticus is able to synthesize the lipid intermediates, but is unable to utilize these intermediates for peptidoglyean synthesis. Deoxycholate was included in the incubation mixture in order to minimize the addition of endogenous glycine to the lipid intermediate.8 After incubation at 20? for 30 minutes, the mixture was extracted with 1 liter of nbutanol:6 M pyridinium acetate (2:1), pH 4.2, followed by two extractions with the same volume of n-butanol. The combined extracts were back-washed with 2 liters of water and then taken to dryness and redissolved in 50 ml of chloroform: methanol (1: 1). The yield was 3 X 106 cpm (34%, based on UDP-M\'SurNAc-C14pentapeptide). The extract was placed on a column of O-(diethylaminoethyl) cellulose (DEAEcellulose) (2.5 X 25 cm) and eluted as previously described.7 The radioactive eluate obtained with methanol:6 M pyridinium acetate, pH 4.2 (1:1), was pooled

Complete hydrolysis of steroid conjugates and quantitative extraction of free steroids from urine.

A simple procedure for the serial hydrolysis and extraction of 5-ml urine samples is described. The samples are incubated at pH 4.45 for 24 hours at 87 °C with high concentrations of β-glucuronidase and sulfatases from Helix pomatia. The incubated samples are freeze-dried and the residual solids are repeatedly extracted with a total of 15 ml of chloroform–methanol (1:2, v/v). The overall efficiency is over 99%. A method for the systematic estimation of urinary steroids based on the combined thin-layer and gas–liquid chromatographic analysis of total extracts is outlined.

Micro analysis of copper in lead metal by spectrophotometric method

Traces of copper in lead metal were determined by chloroform extraction and bathocuproine photometric method. The procedure has been established as follows. Lead metal samples are dissolved in nitric acid and the sample solutions (Cu 115 μg) are transferred to separatory funnels and later diluted to about 60 ml. Then 5 ml of ammonium acetate (30%) and 1 ml of hydroxylamine hydrochloride (10%) are added. The pH of these solutions are adjusted at 3.55 with ammonium hydroxide. Two ml of 0.1 % bathocuproine alcohol solution is added and then it is kept standing for 5 minutes. The solution was shaken with 5 ml of chloroform for 3 minutes. The absorbance of copperbathocuproine complexs extracted is measured at 477 mμ, and the copper content is determined by reference to the calibration curve.According to this method any seperatory procedure from other elements in lead metal is unnecessary in advance. Therefore, it is recommended to be a simple. and rapid procedure for the analysis.

Determination of Scandium in Minerals and Sea-Water

Scandium was determined in mineral and sea-water samples by a spectrophotometric method with 5,7-dichloroxine. The procedure is as follows: 0.5 to 1 g of mineral sample is treated wtth HF and dissolved in HCl. 100 to 200 mg of Ca/sup 2+/ as a carrier and oxalic acid solution are added and pH of the solution is adjusted to 1.8. After standing overnight, the precipitate is ignited and the residue is dissolved in HCl. Sc is separated by extracting at pH 1.5 with 10 ml of 0.2 M TTA--benzene followed by back extracting with 20 ml of 1 N HCl. After Fe and other interfering elements are pre-extracted at pH 3 as 5,7- dichloroxinate, the Sc chelate is successively extracted at pH 9.5 with 10 ml of chloroform. Absorbances are measured at 397 m mu against the reagent blank. Sc in sea water is concentrated also by coprecipitating with Ca oxalate, using each 200 ml of 2 N oxalic acid for 20 l of sample. Several mineral samples such as bauxite, garnet, lepidolite, and fluorspar were analyzed, and a Sc content of 10/ sup -3/ to 10/sup -4/ was obtained. Sc in sea water collected at offshore Misaki- cho gave themore » order of 10/sup -3/ mu g/l. (auth)« less

ウラン中の微量ニッケルの定量ジメチルグリオキシム-クロロホルム抽出光度法

A spectrophotomstric method is critically examined for the determination of microgram quantities of nickel in uranium with dimethylglyoxime. Nickel is determined spaectrophotometrically after extracting its dimethylglyoxime complex with chloroform. Approximately 30 ml of acid solution containing not more than 2.5 g of uranium and 150 mu g of nickel is treated with 10 mi of 30% ammonium citrate solution, 1 ml of 1% dimethylglyoxime solution (1 g in 100 ml of 95% ethanol), and the proper amount of ammonium hydroxide to adjust the pH to 8.8 to 10, and ths volume is brought to 50 ml. Then, the nickel complex is extracted with exactly 10 ml of chloroform, and the absorbance of the extract is measured at 375 m mu using a blank as reference. By this method, as small as 5 mu g of nickel in 2.5 g of uranium can be determined rapidly and accurately. The method provides for ths presence of other metals. (auth)