To Model Chemical Reactivity in Heterogeneous Emulsions, Think Homogeneous Microemulsions

Two important and unsolved problems in the food industry and also fundamental questions in colloid chemistry are how to measure molecular distributions, especially antioxidants (AOs), and how to model chemical reactivity, including AO efficiency in opaque emulsions. The key to understanding reactivi...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1999. - 31(2015), 33 vom: 25. Aug., Seite 8961-79
1. Verfasser: Bravo-Díaz, Carlos (VerfasserIn)
Weitere Verfasser: Romsted, Laurence Stuart, Liu, Changyao, Losada-Barreiro, Sonia, Pastoriza-Gallego, Maria José, Gao, Xiang, Gu, Qing, Krishnan, Gunaseelan, Sánchez-Paz, Verónica, Zhang, Yongliang, Dar, Aijaz Ahmad
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2015
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article
LEADER 01000naa a22002652 4500
001 NLM247387770
003 DE-627
005 20231224145112.0
007 cr uuu---uuuuu
008 231224s2015 xx |||||o 00| ||eng c
024 7 |a 10.1021/acs.langmuir.5b00112  |2 doi 
028 5 2 |a pubmed24n0824.xml 
035 |a (DE-627)NLM247387770 
035 |a (NLM)25805058 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Bravo-Díaz, Carlos  |e verfasserin  |4 aut 
245 1 3 |a To Model Chemical Reactivity in Heterogeneous Emulsions, Think Homogeneous Microemulsions 
264 1 |c 2015 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Completed 03.11.2015 
500 |a Date Revised 25.08.2015 
500 |a published: Print-Electronic 
500 |a Citation Status PubMed-not-MEDLINE 
520 |a Two important and unsolved problems in the food industry and also fundamental questions in colloid chemistry are how to measure molecular distributions, especially antioxidants (AOs), and how to model chemical reactivity, including AO efficiency in opaque emulsions. The key to understanding reactivity in organized surfactant media is that reaction mechanisms are consistent with a discrete structures-separate continuous regions duality. Aggregate structures in emulsions are determined by highly cooperative but weak organizing forces that allow reactants to diffuse at rates approaching their diffusion-controlled limit. Reactant distributions for slow thermal bimolecular reactions are in dynamic equilibrium, and their distributions are proportional to their relative solubilities in the oil, interfacial, and aqueous regions. Our chemical kinetic method is grounded in thermodynamics and combines a pseudophase model with methods for monitoring the reactions of AOs with a hydrophobic arenediazonium ion probe in opaque emulsions. We introduce (a) the logic and basic assumptions of the pseudophase model used to define the distributions of AOs among the oil, interfacial, and aqueous regions in microemulsions and emulsions and (b) the dye derivatization and linear sweep voltammetry methods for monitoring the rates of reaction in opaque emulsions. Our results show that this approach provides a unique, versatile, and robust method for obtaining quantitative estimates of AO partition coefficients or partition constants and distributions and interfacial rate constants in emulsions. The examples provided illustrate the effects of various emulsion properties on AO distributions such as oil hydrophobicity, emulsifier structure and HLB, temperature, droplet size, surfactant charge, and acidity on reactant distributions. Finally, we show that the chemical kinetic method provides a natural explanation for the cut-off effect, a maximum followed by a sharp reduction in AO efficiency with increasing alkyl chain length of a particular AO. We conclude with perspectives and prospects 
650 4 |a Journal Article 
700 1 |a Romsted, Laurence Stuart  |e verfasserin  |4 aut 
700 1 |a Liu, Changyao  |e verfasserin  |4 aut 
700 1 |a Losada-Barreiro, Sonia  |e verfasserin  |4 aut 
700 1 |a Pastoriza-Gallego, Maria José  |e verfasserin  |4 aut 
700 1 |a Gao, Xiang  |e verfasserin  |4 aut 
700 1 |a Gu, Qing  |e verfasserin  |4 aut 
700 1 |a Krishnan, Gunaseelan  |e verfasserin  |4 aut 
700 1 |a Sánchez-Paz, Verónica  |e verfasserin  |4 aut 
700 1 |a Zhang, Yongliang  |e verfasserin  |4 aut 
700 1 |a Dar, Aijaz Ahmad  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Langmuir : the ACS journal of surfaces and colloids  |d 1999  |g 31(2015), 33 vom: 25. Aug., Seite 8961-79  |w (DE-627)NLM098181009  |x 1520-5827  |7 nnns 
773 1 8 |g volume:31  |g year:2015  |g number:33  |g day:25  |g month:08  |g pages:8961-79 
856 4 0 |u http://dx.doi.org/10.1021/acs.langmuir.5b00112  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_22 
912 |a GBV_ILN_350 
912 |a GBV_ILN_721 
951 |a AR 
952 |d 31  |j 2015  |e 33  |b 25  |c 08  |h 8961-79