in order to formulate an efficient and durable mucoadhesive drug delivery system, careful consideration of formulation-related parameters is critical. this study was conducted to investigate the effect of the presence of various types and concentrations of surfactants within or outside carbopol 934 (c934) as well as hydroxypropylmethyl cellulose (hpmc) solid compacts, on their duration of mucoa...

Bearing a hydrophilic part and a hydrophobic part, surfactants can adsorb onto interfaces and lower the tension (γ) of the interfaces, thereby enhancing the interfacial properties and leading to the applications of surfactants in cleaning, surface functionalization, foaming and emulsification. To understand how they work in these applications it is important to know the time-scales of the surfa...

1,4-Dioxane impurity in nonionic surfactants and cosmetics were analyzed using solid-phase microextraction (SPME) coupled with gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Experimental results show that there is no significant difference using SPME-GC and SPME-GC-MS for analysis of 1,4-dioxane in three types of nonionic surfactants at the 95% confidence level. The r...

A nonionic surfactant, n-dodecyl glyceryl itaconate (DGI), self-assembles into bilayer membranes in water having a spacing distance of sub-micrometer in the presence of small amounts of ionic surfactants, and shows beautiful iridescent color. Ionic surfactants have strong effects on this iridescent system. We have interestingly found that the iridescent color changes with time after mixing DGI ...

The influence of surfactants (anionic sodium dodecyl sulfate, and nonionic tert-octylphenol ethoxylate with 9.5EO) and their mixtures on the adsorption of carboxymethylcellulose (CMC) in the presence of 0.001 M NaCl on the manganese dioxide surface (MnO(2)) was studied. The increase in CMC adsorption was observed in all measured systems in the presence of surfactants. The reason for this is the...

The self-associating structures at the solid-liquid interface of three nonionic trisiloxane surfactants ((CH3)3SiO)2Si(CH3)(CH2)3(OCH2CH2)n OH (n = 6, 8, and 12), or BEn, are studied as a function of substrate properties by atomic force microscopy (AFM) imaging and force measurement. These trisiloxane surfactants are known as superwetters, which promote rapid spreading of dilute aqueous solutio...

PURPOSE To investigate the release of surface-active agents (surfactants) from unworn soft contact lenses (SCLs) and their influence on the lens surface wettability in vitro. METHODS Surface tension (ST) of blister pack solutions was measured by pendant-drop technique. STs at the air-aqueous interface and contact angles (CAs) of four conventional and seven silicone hydrogel SCLs were evaluate...

the effect of different kinds of surfactants in various concentrations incorporated in an inert matrix, on the release of procainamide hydrochloride, as a cationic model compound, was investigated in this study. sodium lauryl sulfate and sodium stearate as anionic surfactants, cetyl pyridinium chloride and cetyltrimethyl ammonium bromide as cationic and span 60 and tween 80 as non-ionic surfact...

In this work, we examine the role of curvature and surfactant packing in controlling the structure of periodic silica/surfactant composites by driving such materials through a transformation from a hexagonal to a lamellar phase. We focus on how the interplay of desired packing and volume constraints dictates the resulting structures. In general, surfactants expand in a complex way upon heating,...

Monomeric thiol surfactants, [C(n)H(2n+1)N(CH(3))(2)CH(2)CH(2)SH]Br, were produced by the cleavage of gemini surfactant containing a disulfide bond in the spacer chain, [C(n)H(2n+1)N(CH(3))(2)CH(2)CH(2)SSCH(2)CH(2)N(CH(3))(2)C(n)H(2n+1)]2Br. The disulfide bond was completely reduced by the addition of four times moles of dithiothreitol in water at room temperature. The critical micelle concentr...