Naslov
Starch as a Clathrate – Direct Potentiometric Determination

Autori
Sakač, Nikola ; Sak-Bosnar, Milan ; Babić, Hrvoje ; Karnaš, Maja ; Lajoš, Petar

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
XXIII. hrvatski skup kemičara i kemijskih inženjera : Knjiga sažetaka = XXIII Croatian Meeting of Chemists and Chemical Engineers : Book of abstracts / Hadžiev, Andrea ; Blažeković, Zdenko - Zagreb : Hrvatsko društvo kemijskih inženjera i tehnologa (HDKI) ; Hrvatsko kemijsko drustvo, 2013, 228-228

ISBN
978-953-6894-50-5

Skup
Hrvatski skup kemičara i kemijskih inženjera (23 ; 2013)

Mjesto i datum
Osijek, Hrvatska, 21.04.2013. - 24.04.2013

Vrsta sudjelovanja
Poster

Vrsta recenzije
Domaća recenzija

Ključne riječi
starch ; clatrate ; direct potentiometry

Sažetak
Starch generally consists of two different fractions, amylose, (linear α-1, 4 linked polymer) and amylopectin, (α-1, 6 branched α-1, 4 polymer). A helical structure for starch was proposed in 1937 [1], and there appear three double helix structures – type A, B and V. Type V has the biggest central cavity which leads to the ability of starch to absorb linear molecules. Complexing agents may include any molecule with a lipophilic component, and a structure with a diameter of 4.5– 6 Å. Linear α-helical regions of starch helix form an inclusion (or clathrate) compounds with single- tailed surfactants and triiodide ions. Recently, we published a triiodide-starch complex redox electrode response mechanism [2]. We also published a paper on a new potentiometric surfactant sensor electrode [3] preparation and usage based on a highly lipophilic 1, 3-didecyl-2- methyl-imidazolium (DMI) cation and a tetraphenylborate (TPB) antagonist ion. This compound was used as a sensing material and incorporated into the plasticized PVC-membrane. Direct potentiometry measurements were used to monitor the potential change in starch inclusion complex forming: a) platinum redox electrode//Ag/AgCl electrode system was used to monitor triiodide ion-starch complex formation by starch addition and fixed triiodide ion concentration , and b) a potentiometric surfactant sensor electrode//Ag/AgCl electrode system was used to monitor the surfactant-starch complex formation with fixed starch amount and increasing surfactant concentration. Presented data showed a redox potential change in both cases, a) decrease of the potential as a result of starch-triiodide inclusion formation and decrease of triiodide ion concentration, and b) shifted potential increase in starch solution compared to surfactant response in pure water, representing a surfactant immobilization in starch-surfactant inclusion complex.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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