University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Food -> sweetener -> artificial

Citations 6

"Flow Injection Potentiometric Determination Of Saccharin In Dietary Products With Relocation Of Filtration Unit"
Talanta 1994 Volume 41, Issue 5 Pages 731-734
Orlando Fatibello-Filho* and Joaquim Araújo NóbregaAntonio José Moraes Guaritá-Santos,

Abstract: Saccharin was precipitated as mercurous saccharinate with mercurous nitrate and the excess of the mercurous cation was potentiometrically measured using a Ag wire coated with a Hg film as the working electrode. The potentiometric cell included an Ag/AgCl reference electrode and a stainless-steel tube as counter electrode. A 0.2 M NaNO3 solution in 1 mM HNO3 was used as the carrier solution Saccharin was determined in four commercial sweeteners, viz., Dietil, Sucaryl, Assugrin and Doce Menor. Results were comparable with those obtained by UV spectrophotometry. The calibration graph was linear from 2-10 mM saccharin.
Saccharin Potentiometry Electrode Method comparison Filter

"Indirect Determination Of Cyclamate By An Online Continuous Precipitation-dissolution Flow System"
Talanta 1998 Volume 45, Issue 6 Pages 1115-1122
M. C. Yebra* and P. Bermejo

Abstract: A continuous-flow procedure is proposed for the indirect determination of sodium cyclamate by an atomic absorption spectrometric method in artificial sweeteners mixtures and soft drinks. Sulfamic group is oxidized to sulfate and it is continuously pptd. with lead ion in a flow manifold. The lead sulfate formed is retained on a filter, washed with diluted ethanol and dissolved in ammonium acetate for online atomic absorption determination of lead, the amt. of which in the ppt. is proportional to that of cyclamate in the sample. The proposed method allows the determination of sodium cyclamate in the range 1-90 µg mL-1 with a relative standard deviation of 3.1% at a rate of ~35 samples per h. The 3s detection limit is 0.25 µg mL-1. The method is very selective, no compounds normally found in the analyzed samples and other artificial sweeteners had any effect on the determination of cyclamate.
Cyclamate Spectrophotometry Precipitation Indirect Interferences

"Flow Injection Spectrophotometric Determination Of Aspartame In Dietary Products"
Analyst 1994 Volume 119, Issue 9 Pages 2101-2104
Joaquim de Araújo Nóbrega, Orlando Fatibello-Filho and Iolanda da Cruz Vieira

Abstract: A flow injection spectrophotometric method has been developed for the determination of aspartame in dietary products using ninhydrin as a colorimetric reagent. The reaction was conducted in a 1 + 1 v/v methanol-isopropanol medium also containing potassium hydroxide. The absorbance measurements were made at 603 nm. The results obtained for the determination of aspartame in table sweetener, pudding, gelatin, and refreshment (i.e., a powder dissolved in water for drinking) are in good agreement with the results obtained using a conventional manual procedure (correlation coefficient, r = 0.9984). Thirty-six results were obtained per hour, and the relative standard deviation was less than 3.5% (n = 6) for all samples. The detection limit (three times the signal blank/slope) was 3.8 x 10^-5 mol L-1 of aspartame. Sample (0.2-0.6 g) was stirred with 10 mL of methanol/propan-2-ol (1:1; solvent A) for 2 min. The suspension was filtered and the filtrate was diluted to 25 mL with solvent A. A portion of the solution was injected into a carrier stream (2.5 ml/min) of solvent A and subsequently merged with streams (both 0.3 ml/min) of 0.293 M KOH and 0.037 M ninhydrin (both in solvent A). The mixture was transported to a helical reaction coil (2 m x 0.8 mm i.d.) immersed in a water-bath kept at 60°C. The solution then passed through a de-bubbler after which the absorbance was measured at 603 nm. A diagram of the manifold used is given. The calibration graph was linear from 0.34-2.4 mM aspartame, the detection limit was 38 µM and the RSD (n = 6) was 3.5%. Recoveries were quantitative and the throughput was 36 samples/h. The method was applied to several dietary products, viz., table sweetener, pudding, gelatin and refreshment powder.
Aspartame Spectrophotometry Heated reaction

"Flow Injection Spectrophotometric Determination Of Cyclamate In Low Calorie Soft Drinks And Sweeteners"
Analyst 1995 Volume 120, Issue 7 Pages 2009-2012
Sandro Thomaz Gouveia, Orlando Fatibello-Filho and Joaquim de Araújo Nóbrega

Abstract: The soft drink was agitated for 15 min to remove CO2. Ascorbic acid, if present, was oxidized by passing air through the drink for 20 min. A portion (5-7 ml) of the soft drink was then diluted to 25 mL with water and adjusted to 0.1 M H3PO4. Liquid sweetener (0.5 ml) was diluted to 500 mL with 0.1 M H3PO4. The sample was passed through an alumina column (5 cm x 3.5 mm i.d.) before injection into carrier stream (2.11 ml/min) of 0.1 M H3PO4. The solution was merged with a reagent stream (1.14 ml/min) of 45 µM-nitrite and then passed through a tubular reactor (360 cm) before merging with a colorimetric reagent stream (1.14 ml/min) of 1% sulfanilamide and 0.05% N-1-naphthylethylenediamine dichloride in 0.5 M H3PO4. The mixture passed through a second tubular reactor (100 cm), then through a de-bubbler to remove N2 after which the absorbance was measured at 535 nm. A diagram of the manifold used is given. The detection limit was 30 µM of cyclamate, the RSD (n = 12) was 0.5% and recoveries were 97-102.2%. The throughput was 24 samples/h. The results agreed with those obtained by bi-amperometric titration.
Cyclamate Spectrophotometry Alumina Method comparison

"Biamperometric Titration And Flow Injection Determination Of Cyclamate In Low-calorie Products"
Analyst 1995 Volume 120, Issue 9 Pages 2407-2412
Orlando Fatibello-Filho, Milton Duffles Capelato and Silvana Aparecida Calafatti

Abstract: Two methods for cyclamate (I) determination are described. In the titrimetric method, a portion (5 ml) of the sample in 1 M H3PO4 was titrated with 0.1 M NaNO2, with biamperometric detection at two Pt electrodes polarized at +0.7 V vs. Ag/AgCl. In the flow injection (FI) method, a portion (0.25 ml) of the sample in 1 M H3PO4 was injected into a carrier stream (2.96 ml/min) of 1 M H3PO4 containing 0.001% Triton X-100. The sample/carrier stream was merged with a reagent stream (0.77 ml/min) of 0.1 M NaNO2. The mixture was passed through a 50 cm coiled reactor before biamperometric detection of two Pt electrodes polarized at +0.7 V vs. Ag/AgCl. For the titrimetric method, the calibration graph was linear from 10 to 60 mM I, the detection limit was 1.3 mM and the RSD (n = 9) was 1%. Recoveries of I were 97.6-102.5%. For the FI method, the calibration graph was linear from 5 to 40 mM I, the detection limit was 2.5 mM and the RSD (n = 10) was 1.2%. Recoveries of I were 97.8-102.4%. The throughput was 90 samples/h. The methods were applied to various low-calorie products, viz., sweeteners, puddings, jellies and soft drinks.
Cyclamate Biamperometry Electrode Surfactant Triton X Titrations

"Enzyme-catalysed Determination Of The Sweetner Aspartame"
GIT Fachz. Lab. 1992 Volume 36, Issue 3 Pages 199-204
Hummel, W.;Zervosen, U.

Abstract: Details are given of a flow injection analysis method for the determination of aspartame (I) in sweeteners. Sample was dissolved in water and a portion of the solution was injected into a stream of 50 mM Tris - HCl buffer of pH 8.5 which merged with a stream of the same buffer containing 2.5 mM NAD+. The mixture flowed sequentially through columns (15 mm x 3 mm) packed with pronase, chymotrypsin and phenylalanine dehydrogenase immobilized on to controlled-pore glass and the NADH formed was measured fluorimetrically. The detection limit was 0.2 mM I and 30 samples h-1 could be analyzed.
Aspartame Fluorescence Immobilized enzyme Controlled pore glass Column