Cyclamate conductivity

Abbott Laboratories, which has conducted additional toxicity and carcinogenicity studies with cyclamate, a 10 1 mixture of cyclamate—saccharin, and cyclohexylamine, claimed to be unable to confirm the 1969 findings. Abbott then filed a food additive petition for cyclamate in 1973, which was denied by the FDA in 1980. In 1982, the Calorie Control Council and Abbott Laboratories filed a second food additive petition containing the results of additional safety studies (73). That petition was stiU pending as of 1996. Cyclamate is, however, allowed for use in any or all three categories, ie, food, beverage, and tabletop, in about 50 countries. Sweet n Low, known in the United States as a saccharin-based table-top sweetener, contains exclusively cyclamate in Canada. 

These reactions can also be conducted in an undivided cell, as shown in the case of aryl halides bearing an unsaturated chain (Table 7, entry 7b). Cyclam and other tetradentate donor ligands associated with nickel were used, magnesium being the most convenient anode in these reactions [75-77]. 

Since cyclamate has poor UV absorbing characteristics, HPLC methods for the analysis of this sweetener require specific detection systems, such as indirect photometry or conductivity. Herrmann et al. (24) used indirect photometry for the detection of cyclamate at 267 nm against a UV-absorbing mobile-phase component, p-toluenesulphonate. Biemer (17) and Wu et al. (47) used a conductivity detector for the determination of cyclamate. According to Biemer (17) the use of this detector offers distinct advantages, since compounds coeluting with cyclamate may not exhibit an electrochemical response and, hence, not appear in the chromatogram. 

Acesulfame-K, cyclamate, saccharin Dionex AS4A anion separator column Na2CO, (140 mg/L) Conductivity 17... 

Fig. 8-79. Analysis of cyclamate in chewing gum. - Separator column IonPac AS4A eluent 0.0017 mol/L NaIlC03 flow rate 2 mL/min detection suppressed conductivity injection 50 pL of a spiked chewing gum sample (taken from [70]).

Certain xenobiotic alcohols and amines react with natural fatty acids to form nonpolar conjugates. Hany of the early Investigations In this area were conducted by Edith Lelghty and her coworkers who found fatty acid derivatives of the following DDOH, a DDT metabolite ( ) several tetrahydrocannablnols (25,26, also cf. cyclohexylamlne, from cyclamate ( ) codeine (29) trl-... 

HPLC with reversed-phase (RP) or ion-pair RPLC and UV detection is the most popular choice for the determination of aspartame, saccharin, and acesulfame-K. However, the lack of a chromophore in the cyclamate molecule makes its determination difficult using the common HPLC-UV detection mode. A high-performance anion-exchange chromatographic method with UV and conductivity detectors connected in series offers an attractive alternative for simultaneous determination of the four sweeteners and also citric acid. 

Sweeteners such as saccharine, sodium cyclamate, and acesulfam-K are more and more frequently used in food industry instead of sugar or glucose syrup. These compounds in alkaline medium exist as anions, thus anion-exchange chromatography with conductivity detection provides an alternative to reversed-phase liquid chromatography (RPLC) with UV/Vis detection. ... 

Figure 10.266 Analysis of cyclamate in a chewing gum sample. Separator column lon-Pac AS4A eluent 1.7mmol/L NaHC03 flow rate 2mL/min detection suppressed conductivity injection volume 50 pL sample spiked...

A monomeric molecule of a nickel (Il)-cyclam derivative covalently linked to pyrrole has been synthesized, resulting in an adhesive conducting film on glassy carbon which presents a reversible behaviour of the Ni(III)/Ni(II) couple [190]. 

Bergamoa, A.B., Silvaa, J. A.F and Jesusa, D.P. (2011) Simultaneous determination of aspartame, cyclamate, saccharin and acesulfame-K in soft drinks and tabletop sweetener formulations by capillary electrophoresis with capacitively coupled contactless conductivity detection. Food Chem., 124, 1714-1717. 

Some sweeteners (aspartame, cyclamate, saccharin, and acesulfame K) were determined by CE-SIA with contactless conductivity detection (Stojkovic et al., 2013). The analyses were carried out in an aqueous running buffer consisting of 150 mM 2-(cyclo-hexylamino)ethanesulfonic acid and 400 mM tris(hydroxymethyl)aminomethane at pH 9.1 in order to render all analytes in the fully deprotonated anionic form. The four compounds were determined successfully in food samples the experimental set-up and typical analysis results are illustrated in Figure 2.9. Another SIA system combined with solenoid valves was used to automate an enzymatic method for the determination of aspartame in commercial sweetener tablets. The method involves the enzymatic conversion of aspartame to hydrogen peroxide by the chymotrypsin-alcohol oxidase system, followed by the use of 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ARTS) as electron donor for peroxidase. Chymotrypsin and alcohol oxidase enzymes were immobilized on activated porous silica beads (Pena et al., 2004). 

Only two flow analysis methods have been published for multianalyte determination including cyclamate as analyte. Both methods determine cyclamate with other artificial sweeteners. One of them used stabilized systems of filter-supported BLMs in a FIA manifold [72], and the other is based on CE with contactless conductivity detection employing a sequential injection manifold based on a syringe pump [77]. 

Saccharin was determined in multianalyte mode, as well as acesulfame-K and cyclamate, by CE with contactless conductivity detection employing a sequential injection manifold based on a syringe pump [77]. 

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