Chelating surfactants

Inspired by the many hydrolytically-active metallo enzymes encountered in nature, extensive studies have been performed on so-called metallo micelles. These investigations usually focus on mixed micelles of a common surfactant together with a special chelating surfactant that exhibits a high affinity for transition-metal ions. These aggregates can have remarkable catalytic effects on the hydrolysis of activated carboxylic acid esters, phosphate esters and amides. In these reactions the exact role of the metal ion is not clear and may vary from one system to another. However, there are strong indications that the major function of the metal ion is the coordination of hydroxide anion in the Stem region of the micelle where it is in the proximity of the micelle-bound substrate. The first report of catalysis of a hydrolysis reaction by me tall omi cell es stems from 1978. In the years that... 

Arnold and co-workers attempted to prepare imprinted metal-coordinating polymers for proteins [25]. For this purpose, efforts were made to prepare metalcoordinating molecularly patterned surfaces in mixed monolayers spread at the air-water interface or liposomes. This approach was termed as molecular printing and is illustrated in Fig. 6.6. In this process, a protein template is introduced into the aqueous phase, which imposes a pattern of functional amphiphiles in the surfactant monolayer via strong interactions with metal-chelating surfactant head groups. The pattern is then fixed by polymerising the surfactant tails. The technique has also been employed for two dimensional crystallisation of proteins [26]. 

Hampshire [Grace], TM for chemical products, namely, amino acids, chelating agents, metal chelates, surfactants, sequestering agents, and resins. 

U.S. 6503873 (2002) Crudden et al. (Hampshire Chem) JV-acyl ethylenediaminetriacetic acid (ED3A) (Na or K lauroyl) A novel chelating surfactant product ultra-mild detergent compositions in combination with alkyl sulfates excellent lather stability... 

Affinity surfactants and cosurfactants Alkyl monoglucoside (Concanavalin A) Boronic acid derivatives (a-chymotrypsin) Surfactants with biotin-containing headgroup (Avidin) Metal chelating surfactant (cytochrome c) Cholesteryl-D-alanyl-D-alanine (Vancomycin) [30,31,34-36] [35] [37,38] [39] [40]... 

Toxicology TSCA listed Uses Chelating surfactant for personal care, cleansing, body washes, industrial applies. Trade Name Synonyms Hampshire LEDSANAx Sol n. [Hampshire http //www. dow. com/hampshire]... 

Takeshita et al. [70-72] made a systematic study of EDTA-derived surfactants. For ethylene alkyl EDTA chelate surfactant, it was found that the properties of the chelating surfactant were greatly influenced by the nature of the metal ions. Cu chelate surfactant showed a lower specific surface tension... 

Larpent C, Prevost S, Berthon L, Zemb T, Testard F (2007) Nonionic metal-chelating surfactants mediated solvent-free thermo-induced separation of ura-nyl. New J Chem 31(8) 1424-1428... 

The Interaction Parameter in Binary Surfactant Mixtures of a Chelating Surfactant and a Foaming Agent... 

Keywords p parameter electrostatic interaction mixed micellisation chelating surfactant amphoteric surfactant... 

Figure 1 Chemical structure of the amphoteric chelating surfactant 2-dodecyldiethylenetriamine pentaacetic acid, 4-Ci2-DTPA. The amine groups become protonated and the carboxyl groups dissociated at various degree depending on the pH. In the examined pH span, 4-Ci2-DTPA is zwitterionic with a negative net charge...

Furthermore, the interactions of the chelating surfactant with the anionic sodium dodecyl sulphate, SDS, were examined. SDS interacts favorably with the local positive charge of 4-Ci2-DTPA, and synergism was observed also in the 4-C12-DTPA/SDS system, as can be seen in Figure 3 where the cmc is plotted versus solution composition for the 4-Ci2-DTPA/SDS system at pH 5.0. 

N Acyl ED3A Chelating Surfactants Properties and Applications in Detergency... 

II. STRUCTURE AND SYNTHESIS OF N-ACYL ED3A CHELATING SURFACTANTS... 

N-acyl ED3A chelating surfactants when evaluated for surfactant and chelating properties exhibited a wide range of unique and unexpected features. Many of these properties are extremely desirable in detergent systems ... 

N-acyl ED3A chelating surfactants are capable of very dramatic, highly synergistic lather enhancement on mixed surfactant systems particularly in the presence of divalent connterions. The lather stability on mixtnres of SLES (3 moles EO) and Na LEDS A at a constant concentration of 1% in the presence and absence of water hardness is presented in Figure 5. Synergistic lather enhancement is evident when the system composition passes 30% LED3A. 

A Terg-o-tometer study was carried out to determine the compatability of N-acyl ED3A chelating surfactants with Savinase, a protease enzyme [13]. Myristoyl and Oleoyl ED3 A were neutralized with aqueous sodium hydroxide to produce 20 (w/w)% solutions and 10 g of the solutions were diluted to 1L with distilled deionized water. The surfactant solution was then decanted into four of the Terg-o-tometer cells and allowed to equilibrate to 25°C. One milliliter of protease enzyme solution (Savinase 16.0L type EX) was diluted to 100 mL with distilled deionized... 

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