scholarly journals Reverse vesicles as a new system for studying enzymes in organic solvents

1992 ◽  
Vol 285 (2) ◽  
pp. 373-376 ◽  
Author(s):  
A Sánchez-Ferrer ◽  
F García-Carmona
Keyword(s):  
Aqueous Solution ◽  
Organic Solvents ◽  
Reverse Micelles ◽  
Active Form ◽  
Ionic Surfactant ◽  
New Approach ◽  
Optically Transparent ◽  
Reverse Vesicles ◽  
Dodecyl Ether ◽  
New System

A new approach to the study of enzyme activity in organic solvents has been developed by using optically transparent reverse vesicles. Polyphenol oxidase was incorporated in an active form into the above ternary system formed by the non-ionic surfactant tetra(ethylene glycol) dodecyl ether/n-dodecane/water. The enzyme in this microenvironment, surprisingly, showed an apparent positive co-operativity which has never before been described either in aqueous solution or in reverse micelles. In addition, the Vmax. expressed was similar to that in water and twice that displayed in reverse micelles.

Degumming of Mulberry Silk with Papain in Non-Aqueous Systems

2013 ◽  
Vol 821-822 ◽  
pp. 467-470
Author(s):  
Sheng Sun ◽  
Shi Xiong Yi ◽  
Nan Zhang
Keyword(s):  
Aqueous Solution ◽  
Weight Loss ◽  
Surface Morphology ◽  
Reverse Micelles ◽  
Ionic Surfactant ◽  
Aqueous Systems ◽  
Reverse Trend ◽  
Triton X

The nonionic reverse micelles used for degumming of mulberry silk were prepared with a non-ionic surfactant Triton X-100 (TX-100) by injecting small amount of papain aqueous solution. The weight loss of mulberry silk degummed at different concentration of papain in TX-100 reverse micelles was investigated. The effect of the amount of solubilized water was also discussed. The polarizing optic microscope was employed to observe the surface morphology of the mulberry silk. The results indicated that the weight loss of the mulberry silk was increased with increasing concentration of papain, but the W values exhibited the reverse trend. The good degumming of mulberry silk with papain was obtained in TX-100 reverse micelles. The strength of mulberry silk decreased with increasing concentration of papain.

scholarly journals A novel route to size-controlled MIL-53(Fe) metal–organic frameworks for combined chemodynamic therapy and chemotherapy for cancer

RSC Advances ◽  
2021 ◽  
Vol 11 (18) ◽  
pp. 10540-10547
Author(s):  
Anxia Li ◽  
Xiaoxin Yang ◽  
Juan Chen
Keyword(s):  
Drug Delivery ◽  
Therapeutic Approach ◽  
Metal Organic Frameworks ◽  
Ionic Surfactant ◽  
Controlled Synthesis ◽  
New Approach ◽  
Metal Organic ◽  
Size Controlled

In this study, we reported a new approach for the size-controlled synthesis of uniform iron(iii)-based MIL-53 nanocrystals using the non-ionic surfactant PVP. A combinational therapeutic approach was presented for drug delivery and ROS therapy.

A New Approach to Fluorescent Chemosensor of Cu2+ Ion

2014 ◽  
Vol 513-517 ◽  
pp. 65-69
Author(s):  
Xiao Jun Hu ◽  
Xin Yan Hu ◽  
Zhi Zhang
Keyword(s):  
Aqueous Solution ◽  
Electron Transfer ◽  
Self Assembly ◽  
Ph Value ◽  
Sodium Dodecyl ◽  
Fluorescence Emission ◽  
Fluorescent Chemosensor ◽  
Dynamic Quenching ◽  
Transfer Effects ◽  
New Approach

According to the principle of dynamic quenching a new ON-OFF fluorescent chemosensor for Cu2+ions was designed, this chemosensor was composed of p-tert-butylthiacalix [arene (TCA),sodium dodecyl sulfate (SDS) and perylene through the form of self-assembly in aqueous solution. Addition of Cu2+ions could result in a quenching of the fluorescence emission of perylene inside micelles, which due to intramicellar complex-fluorophore electron-transfer or energy-transfer effects induced by the complexation of TCA with the Cu2+ions.The experimental results indicated that: Under the condition of TCA/perylene was 800/1, SDS concentration was 150mmol/L and pH value above 9, according to the fluorescence quenching ,within a certain range of the concentration of Cu2+ion can be linearly determined.

scholarly journals Modification and Improvement of Fe3O4-Embedded Poly(thiophene) Core/Shell Nanoparticles for Cadmium Removal by Cloud Point Extraction

2020 ◽  
Vol 1 (1) ◽  
pp. 20-27
Keyword(s):  
Aqueous Solution ◽  
Cloud Point ◽  
Cloud Point Extraction ◽  
Calibration Graph ◽  
Nano Particles ◽  
Extraction Time ◽  
Ionic Surfactant ◽  
Nano Particle ◽  
Cadmium Removal ◽  
Shell Nanoparticles

Cloud Point Extraction (CPE) as an effective method for pre-concentration and separation of cadmium from aqueous solution is widely utilized. This study involves a surfactant mediated CPE procedure in order to remove cadmium from waste water using Polythiophene nanoparticle and Triton X- 100 as a non – ionic surfactant. Polythiophene – coated iron nanoparticles was successfully synthesized with novel method and as a super magnetic nano-particles (MNPs) for cadmium removal from aqueous solution was evaluated. Polythophene nano-particles emulsifying method have been synthesized and fabricated. Fabricated nano-particle was characterized by Fourier-transform infrared spectroscopy (FTIR), and analysed transmission electron microscopy (SEM). Effects of pH, buffer volume, extraction time, temperature, amount of nano-particle were essentially investigated. To reach in optimum conditions, related experiments were replicated and accomplished as well. For removal of cadmium by CPE approach the optimization conditions were gained at pH = 7 , volume of buffer acid 1.5 millilitre , electrolyte concentration (NaCl) of 10 -3 mole L-1 , Trinton concentration 5 %, cloud point temperature 80 0 C , extraction time 40 minutes, and 5 mg of modified polythiophene nano-particle. The calibration graph was liner with a correlation coefficient of 0. 9984 and represents appropriate liner correlation with an amount and concentration. The results revealed that 5 gram of modified nanoparticle can significantly increase the efficiency of cadmium removal.

Everything is included in such a calculation, everything can be summed up to that result; we find in it the effects of the chemical, mechanical, physical process, the advan­ tages of activity and workforce discipline, and finally the effect of every resource, of all sorts of economic means, particularly that of a lower capital producing as much or more. The evaluation of each Company, that is to say its contribution to the association, will result from that cost, or return, combined with the number of squarefoot pro­ duced, and with the effective selling price, including of course the quality or the degree of perfection of products. What happened meanwhile in the economic field? Which fac­ tors were strong enough to lead to such a systematic calculation? The conditions of production had slightly evolved in that period, but the main change came from outside the firm. Between 1793 and 1829, the dates of the two preceding quotations, the Company's Privilege disappeared and something new emerged: competition. The upheavals resulting from the Industrial Revolution seemed to have led to the widespread acceptance of cost calcula­ tions as the only efficient means to compare the activities of com­ peting firms. This is particularly true for firms that did not have any competition before 1790. Moreover, one can observe that in­ dustrial accounting and cost accounting books appeared in France from 1817 onwards, and can find several authors of that period saying: “I am the very first to find a new approach to the prob­ lem."6 THE SETTING UP OF THE NEW ACCOUNTING SYSTEM (1820-1834) The proceedings of the Board of Director’s meetings have been preserved; from these it is apparent that a new accounting system began in 1820. However, the actual accounting records from before 1825 have not survived. From the 1825 accounting records, it is clear that there is a new system of reporting which was long in being developed; a Profit and Loss Account was pre-

2014 ◽  
pp. 254-254
Keyword(s):  
Physical Process ◽  
Industrial Revolution ◽  
Cost Accounting ◽  
Selling Price ◽  
Accounting System ◽  
New Approach ◽  
Systematic Calculation ◽  
Widespread Acceptance ◽  
New System ◽  
Main Change
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