The HLB number determination of polyoxyethylene surfactants

1989 ◽  
Vol 54 (4) ◽  
pp. 945-952 ◽  
Author(s):  
Josef Šilha ◽  
Milan Bareš ◽  
Ivo Zeman ◽  
Jan Šmidrkal
Keyword(s):  
Ethylene Oxide ◽  
Lauryl Alcohol ◽  
Relevant Information ◽  
Ionic Surfactants ◽  
Methods Of Determination ◽  
Molar Ratios

The Hydrophile-Lipophile-Balance (HLB) numbers were evaluated on the basis of three different, commonly used methods of determination and calculation, in a series of lauric, resp. stearic acids and lauryl alcohol oxyethylenation products prepared by an alkali-catalyzed reaction in a similar scale of hydrophobe: ethylene oxide molar ratios. The results showed that, due to the different principles of the used methods, the HLB numbers were obtained with a great variance, limiting their use as parameters for estimation of the application effectiveness of non-ionic surfactants of the polyoxyethylene type. The HLB concept was not found able to consider the complicated composition of the studied types of surfactants and to provide relevant information in the already mentioned sense.

scholarly journals A Brief Overview on Antioxidant Activity Determination of Silver Nanoparticles

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3191 ◽  
Author(s):  
Zdenka Bedlovičová ◽  
Imrich Strapáč ◽  
Matej Baláž ◽  
Aneta Salayová
Keyword(s):  
Antioxidant Activity ◽  
Silver Nanoparticles ◽  
Relevant Information ◽  
Review Article ◽  
Activity Determination ◽  
Methods Of Determination

Our objective in this review article is to find out relevant information about methods of determination of antioxidant activity of silver nanoparticles. There are many studies dealing with mentioned problem and herein we summarize the knowledge about methods evaluating the antioxidant activity of silver nanoparticles reported so far. Many authors declare better antioxidant activity of silver nanoparticles compared to the extract used for synthesis of them. In this review, we focused on methods of antioxidant activity determination in detail to find out novel and perspective techniques to solve the general problems associated with the determination of antioxidant activity of silver nanoparticles.

METHODS OF DETERMINATION OF FLUORINE IN COALS AND WASTE OF THEIR PRODUCTION AND PROCESSING

2018 ◽  
Vol 5 (22) ◽  
pp. 3-13
Author(s):  
T.S. Sazonova ◽  
◽  
E.E. Sokolovskaya ◽  
S.A. Silutin ◽  
V.I. Minaev ◽  
...  
Keyword(s):  
Methods Of Determination

Artemisinin (ART) Drug Delivery Using Mixed Non-ionic Surfactants and Evaluation of Their Efficiency in Different Cancer Cell Lines

2017 ◽  
Vol 4 (4) ◽  
Author(s):  
Elnaz Asgharkhani ◽  
Aazam Najmafshar ◽  
Mohsen Chiani
Keyword(s):  
Zeta Potential ◽  
Cell Line ◽  
Mtt Assay ◽  
Therapeutic Index ◽  
Stability Study ◽  
Polydispersity Index ◽  
Ionic Surfactants ◽  
Cytotoxicity Test ◽  
Molar Ratios ◽  
Chemotherapy Agent

This study aims to investigate the effects of different non-ionic surfactants on physicochemical properties of ART niosomes. ART is a natural compound that is used as an antimalarial and chemotherapy agent in medicine. ART has low bioavailability, stability and solubility. In order to solve these problems and enhancing the efficiency of the drug, nanotechnology was used. In the present study, several niosomal formulations of ART prepared using different molar ratios of Span 60 : Tween 60 : PEG-600: ART in PBS. These three formulations were FI (1:1:0.5:0.5), FII (2:1:0.5:0.5) and FIII (1:2:0.5:0.5), respectively. The encapsulation efficiency was measured by HPLC and the drug release was evaluated by dialysis method. The cytotoxicity test was determined by MTT assay. The size, zeta potential and polydispersity index of the vesicles was measured by Zeta Sizer. Stability study was performed within two months. The MTT assay results showed that cytotoxicity effect of these formulations on MCF-7 cell line is better than C6 cell line and the FIII had the best results for both of them. The entrapment efficiencies of the formulations I, II and III were obtained 82.2±1.88%, 75.5±0.92% and 95.5±1.23%, respectively. The results of size, zeta potential and polydispersity index indicated that the size of the vesicles is below 200 nm, their surface charge is about -35 mV and they were monodisperse. Stability and release study indicated that the formulation III has the best stability and release pattern. Therefore, the use of PEGylated niosomal ART can effectively improve its therapeutic index, stability and solubility.

scholarly journals Rapid Determination of Ethylene Oxide and 75 VOCs in Ambient Air with Canister Sampling and Associated Growth Issues

Separations ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 35
Author(s):  
Jason Hoisington ◽  
Jason S. Herrington
Keyword(s):  
Ethylene Oxide ◽  
Rapid Determination ◽  
Complex Mixture ◽  
Ambient Air ◽  
Gas Chromatography Mass Spectrometry ◽  
Average Accuracy ◽  
Relative Standard ◽  
Wide Range ◽  
Us Epa

A canister-based sampling method along with preconcentrator-Gas chromatography-Mass Spectrometry (GC-MS) analysis was applied to ethylene oxide (EtO or EO) and 75 other volatile organic compounds (VOCs) in ambient air. Ambient air can contain a large variety of VOCs, and thorough analysis requires non-discriminatory sampling and a chromatographic method capable of resolving a complex mixture. Canister collection of whole air samples allows for the collection of a wide range of volatile compounds, while the simultaneous analysis of ethylene oxide and other VOCs allows for faster throughput than separate methods. The method presented is based on US EPA Method TO-15A and allows for the detection of EtO from 18 to 2500 pptv. The method has an average accuracy of 104% and precision of 13% relative standard deviation (RSD), with an instrument run time of 32 min. In addition, a link between canister cleanliness and ethylene oxide growth is observed, and potential mechanisms and cleaning strategies are addressed.

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