An o-Toluidine Method for Body-Fluid Glucose Determination

Abstract Since publication of the above paper, we have found that a procedure similar to the one described for determination of aldosaccharides in body fluids using o-toluidine in glacial acetic acid solution was described by Eric Hultman in Nature183, 108 (1959). A modification of Hultman's procedure has recently been described by A. Hyvärinen and E. A. Nikkilä in Clin. Chim. Acta7, 140 (1962). The omission of reference to Dr. Hultman's paper was entirely unintentional. Our own procedure was, of course, derived entirely experimentally, based upon Dr. O. M. Forsell's suggestion to us of Mar. 13, 1960, that we should consider the use of o-toluidine as a glucose reagent; and this suggestion is properly credited in the paper as a personal communication. The papers by Hultman and by Hyvärinen and Nikkilä nicely confirm some of the significant experimental details and results of our procedure; but obviously the Hultman paper has priority with respect to this principle.

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Determination of Chlorbenside Residues Including Its Sulfoxide and Sulfone Oxidation Products

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/49.2.407 ◽

1966 ◽

Vol 49 (2) ◽

pp. 407-412

Author(s):

Harry Shuman ◽

Ugo R Cieri

Keyword(s):

Gas Chromatography ◽

Acetic Acid ◽

Acid Solution ◽

Aluminum Oxide ◽

Electron Capture ◽

Acetic Acid Solution ◽

Extraction Procedure ◽

Oxidation Products ◽

Aluminum Oxide Column

Abstract A method is presented for determining residues of chlorbenside including its sulfoxide and sulfone oxidation products. The method employs the Mills-Onley-Gaither extraction procedure. Chlorbenside and chlorbenside sulfoxide are converted to chlorbenside sulfone by a short oxidation with chromic-acetic acid solution. Chlorbenside sulfone is isolated from interfering pesticides and most oxidation products on an aluminum oxide column and determined by electron capture gas chromatography. Recoveries for mixtures of the three components added to apple samples at 0.3–5 ppm (calculated as chlorbenside) were between 92 and 110%.

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Blood Glucose Determination without Deproteinization, with Use of o-Toluidine in Dilute Acetic Acid

Clinical Chemistry ◽

10.1093/clinchem/17.5.440 ◽

1971 ◽

Vol 17 (5) ◽

pp. 440-441 ◽

Cited By ~ 10

Author(s):

Giovanni Ceriotti

Keyword(s):

Acetic Acid ◽

Blood Glucose ◽

Acid Solution ◽

Acetic Acid Solution ◽

Glucose Determination ◽

Blood Glucose Determination

Abstract A method is described for determining glucose in 25 µl of plasma. o-Toluidine is used in weak acetic acid solution. Addition of the emulsifier "Cremophor" obviates the need for deproteinization. The reaction is complete after 15 min at 100°C, and the color is stable for longer than 24 h. The blank is almost colorless. The reagent is stable, colorless, not viscous, and convenient to handle.

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STUDIES ON THE FORMATION OF HEXAMINE

Canadian Journal of Chemistry ◽

10.1139/v52-081 ◽

1952 ◽

Vol 30 (9) ◽

pp. 687-693 ◽

Cited By ~ 1

Author(s):

T. R. Ingraham ◽

C. A. Winkler

Keyword(s):

Activation Energy ◽

Acetic Acid ◽

Acid Solution ◽

Induction Period ◽

Ammonium Nitrate ◽

Sodium Acetate ◽

Glacial Acetic Acid ◽

Initial Rate ◽

Acetic Acid Solution ◽

Rate Data

Rate curves have been determined for the reaction of ammonium nitrate with formaldehyde in glacial acetic acid solution at 25 °C., 35 °C., 45 °C., and 55 °C. over a range of Initial mole ratios (formaldehyde: ammonia) of 0.75:1 to 9.0:1. Data obtained at 25 °C. show a definite induction period in the formation of hexamine. The length of the induction period is not changed by increasing ammonium nitrate concentrations above the theoretical (1.5:1), but may be appreciably shortened by initial additions of excess formaldehyde or of sodium acetate. From 35 °C. upward, the induction period is not apparent. The order of the reaction with respect to formaldehyde has been determined from initial rate data, and an activation energy calculated. The reactions in general appear analogous to those found in slightly acid aqueous systems.

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Determination of Malonaldehyde as an Index of Rancidity in Nut Meats

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/54.5.1024 ◽

1971 ◽

Vol 54 (5) ◽

pp. 1024-1026 ◽

Cited By ~ 1

Author(s):

David C Holland

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Acetic Acid Solution ◽

Meat Products ◽

Thiobarbituric Acid ◽

Taste Panel ◽

Nacl Solution ◽

Red Color ◽

532 Nm

Abstract Distillation of ground walnut meats from a slightly acidified concentrated NaCl solution gives a high per cent recovery of malonaldehyde which is associated with rancidity in nut meat products. Heating an aliquot of the distillate in an acetic acid solution of 2-thiobarbituric acid yields an intense red color with a maximum absorbance at about 532 nm. As little as 0.1 μg malonaldehyde/ml can be measured. Nuts judged to be slightly rancid by a taste panel showed the presence of approximately 40 μg malonaldehyde/g nul meat. Recoveries of malonaldehyde added to samples ranged from 92 to 97%. No malonaldehyde was detected in fresh nut meats.

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A Rapid and Selective Test for Alcohols by Using the Chromium(VI)oxide-pyridine Complex in a Glacial Acetic Acid Solution.

Acta Chemica Scandinavica ◽

10.3891/acta.chem.scand.18-1013 ◽

1964 ◽

Vol 18 ◽

pp. 1013-1014 ◽

Cited By ~ 12

Author(s):

Karl-Erland Stensiö ◽

Carl Axel Wachtmeister ◽

B. Thorkilsen ◽

Hans Halvarson ◽

Lennart Nilsson

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Glacial Acetic Acid ◽

Acetic Acid Solution ◽

Chromium Vi ◽

Pyridine Complex

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Universal Chromatographic-Colorimetric Method for the Determination of Trace Amounts of Polyvinylpyrrolidone and Its Copolymers in Foods, Beverages, Laundry Products, and Cosmetics

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/57.4.796 ◽

1974 ◽

Vol 57 (4) ◽

pp. 796-800 ◽

Cited By ~ 2

Author(s):

Lewis J Frauenfelder

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Silica Gel ◽

Acetic Acid Solution ◽

Colorimetric Method ◽

Ethanol Solution ◽

Laundry Products ◽

Red Dye ◽

Methyl Pyrrolidone

Abstract A chromatographic-colorimetric method has been developed for the determination of trace amounts of polyvinylpyrrolidone (PVP) and its copolymers in foods, beverages, laundry products, and cosmetics. Products containing the PVP are passed through a chromatographic column and the PVP is adsorbed at the top of the column. The column is prepared from silica gel if the sample is soluble in 40% acetic acid solution while Micro-Cel E is used when the sample is soluble in a 50% ethanol solution. The PVP adsorbed on the column is then treated with Vital Red dye and the PVP-dye complex thus formed is eluted with TV-methyl pyrrolidone and measured colorimetrically. From the data obtained it is apparent that the method can detect as little as 0.1 ppm with a reproducibility of ±5% of the amount present.

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