Nanosized Reactors Based on Polyethyleneimines:  From Microheterogeneous Systems to Immobilized Catalysts

Zakharova, L. Ya.; Ibragimova, A. R.; Валеева, Ф. Г.; Захаров, А. В.; Mustafina, Asiya R.; Kudryavtseva, L. A.; Harlampidi, H. E.; Коновалов, А. И.

doi:10.1021/la0629633

Cited by 41 publications

(37 citation statements)

References 66 publications

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“…Depending on the polymer concentration, aqueous solutions of PEI have a pH value of 8.7-9.7. At pH 10, less than 0.5% of PEI amino-groups are protonated (22). pK a values of the methyl-substituted analogue of 1 reported earlier (5, 23) are 9.0^0.08, The greatest change of compression isotherms was observed for the monolayer of 1 on CP subphase.…”

Section: Resultsmentioning

confidence: 61%

Monolayers and Langmuir–Blodgett films of amphiphilic tetramethylsulphonatocalix[4]resorcinarene and their interactions with polyethyleneimine and caeruloplasmin

Мельникова

Kazakova

Guljaev

et al. 2009

Supramolecular Chemistry

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2009) Monolayers and Langmuir-Blodgett films of amphiphilic tetramethylsulphonatocalix[4]resorcinarene and their interactions with polyethyleneimine and caeruloplasmin, Supramolecular Chemistry, 21:6, 532-538,The paper deals with the surface films of amphiphilic tetramethylsulphonatocalixresorcinarene (R ¼ C 11 H 23 ) 1 insoluble in water but forms rigid stable non-collapsing films at the water -air interface. Compression isotherms were used to investigate the interactions of the macrocycle films with two polymers fed to the aqueous subphases: synthetic -polyethyleneimine (PEI) and natural -an oxidase enzyme caeruloplasmin (CP). The interactions of the surface films of 1 with these substrates are predominantly dictated by the nature of the macromolecules and not by macrocycle interactions with their individual fragments. CP having retained its globular structure was extracted in the layer of 1 and became the dominating component of the film. The synthetic macromolecule of PEI, six times lower in its weight than CP, did not affect the morphology of the interfacial film, involved in the interactions only with its hydrophilic part directed inside the water.

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Section: Resultsmentioning

confidence: 61%

Monolayers and Langmuir–Blodgett films of amphiphilic tetramethylsulphonatocalix[4]resorcinarene and their interactions with polyethyleneimine and caeruloplasmin

Мельникова

Kazakova

Guljaev

et al. 2009

Supramolecular Chemistry

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“…In the case of nonionic surfactants, no decrease in CMC is, as a rule, observed upon the addition of a polymer. Previously, we reported a noticeable reduction in CMC and the exist ence of two critical concentrations for PEI based sys tems in the presence of anionic [24] and cationic [25] surfactants. For nonionic surfactants, such as Triton X 100 [13] and С 10 Е 12 [26], one inflection was observed, and the CMC values appeared to be close for solutions of individual surfactants and surfactantpolymer mixtures.…”

Section: Study Of Aggregationmentioning

confidence: 86%

“…Previously [24][25][26], we proposed an approach to the develop ment of supramolecular catalysts, which consists in step by step growth of the catalytic activity. These sys tems are based on a micelle forming component, which provides a contribution of micellar catalysis fac tors, i.e., the effects of concentrating and microenvi ronment.…”

Section: Study Of Catalytic Activitymentioning

confidence: 99%

New organized systems based on amphiphilic oxyethylated calix[4]arene

et al. 2012

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The aggregation of amphiphilic oxyethylated calix [4]arene is studied in the absence and presence of polyethyleneimine. At low calixarene concentrations, large ensembles with a hydrodynamic diameter of about 100 nm are formed and coexist with small (smaller than 10 nm) aggregates, which are observed in the entire concentration range. It is established that calixarene based systems catalyze the neutral hydrolysis of bis(chloromethyl)phosphinic acid p nitrophenyl ester, with the catalytic effect being as high as two orders of magnitude in the presence of La(III) ions. The rate of hydrolysis of phosphonates depends on the composi tion of the supramolecular system. The maximum acceleration exceeds three orders of magnitude in compar ison with alkaline hydrolysis of the substrates.

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“…The details of the experi mental design were described in Ref. 20. The measurement error did not exceed 4%.…”

Section: Methodsmentioning

confidence: 99%

Systems based on nonionic amphiphilic compounds: aggregation and catalytic properties

et al. 2010

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The micellization properties, solubilization capability, and catalytic effect of conventional nonionic surfactants and amphiphilic compounds of oligomeric (Tyloxapol) and polymeric (Synperonic F 68, Pluronic F 127) structure were compared. The systems studied demonstrate a marked catalytic effect toward basic hydrolysis of p nitrophenyl laurate, which exceeds the effect of aqueous alkali solutions by two orders of magnitude. Correlations between the solubili zation capacity of aggregates and their catalytic effect were observed. The maximum efficiency was found for the Tyloxapol solution. The synergetic enhancement of the catalytic effect was observed for the mixed Tyloxapol cetyltrimethylammonium bromide systems in the presence of small amounts of cationic surfactant.Amphiphilic compounds including surfactants and polymers are widely used in gene therapy for transporta tion of medicines and as the catalysts (nanoreactors) sim ulating the basic factors of catalytic action of enzymes. 1-4 Specific features of chemical and biochemical processes occurring in the systems based on surfactants arise from the nanoscale sizes of the reaction zone and from the devel oped area of the interface layer, which determine the be havior of reactants. 5-8 Structural variations in the sub stances forming the interface, as well as directed variation of the contributions of electrostatic, hydrophobic, and spe cific interactions between the surface and the reactants allow one to control the rates of chemical transforma tions. Mixed solutions of amphiphilic compounds are promising for controllable variation of the surface proper ties of aggregates. Previously, 9-12 we have shown that modification of micellar solutions of nonionic surfactants by ionic surfactant additives can be a tool for target con trol of the rates of ion molecular reactions due to the change in the microscopic properties of the interface, such as the surface potential, micropolarity, etc. In particular, a syn ergetic effect in the micelle forming and catalytic proper ties of the systems based on cetyltrimethylammonium bro mide (CTAB) and nonionic surfactants Triton X 100 and Brij 97 was revealed. 9 It was shown 11 that the addition of CTAB to a Triton X 100 solution results in the formation of mixed aggregates in which an increase in the rate of basic hydrolysis of carboxylic acid esters and the acids containing four coordinate phosphorus is observed.The present work is devoted to the study of aggregation of biocompatible amphiphilic nonionic compounds pos sessing the surface activity, to estimation of their solubiliza tion ability toward biologically active compounds, and to control of the reactivity of the latter. Particular attention is paid to the study of aggregation and catalytic activity of the mixed systems based on CTAB and Tyloxapol (non ionic amphiphile with oligomeric structure). Mixed sys tems based on surfactants are widely used in modern tech nologies; 13 therefore, information on the properties of such systems is topical. The mixed systems based on T...

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Nanosized Reactors Based on Polyethyleneimines: From Microheterogeneous Systems to Immobilized Catalysts

Cited by 41 publications

References 66 publications

Monolayers and Langmuir–Blodgett films of amphiphilic tetramethylsulphonatocalix[4]resorcinarene and their interactions with polyethyleneimine and caeruloplasmin

Monolayers and Langmuir–Blodgett films of amphiphilic tetramethylsulphonatocalix[4]resorcinarene and their interactions with polyethyleneimine and caeruloplasmin

New organized systems based on amphiphilic oxyethylated calix[4]arene

Systems based on nonionic amphiphilic compounds: aggregation and catalytic properties

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