Surfactants cetylpyridinium chloride

Figure 12.21 Phase diagram for the surfactants cetylpyridinium chloride and hexanol in 0.2 M NaCl at 30°C. Li is a disordered state of wormy micelles, Nc is the nematic state of oriented micelles, H is a state of hexagonally ordered cylindrical micelles, and L is a lamellar state. The hatched areas are coexistence regions. (Reprinted with permission from Roux et al.. Macromolecules 28 1681. Copyright 1995, American Chemical Society.)...

In 2003, Yates and coworkers[148] explored a new method to prepare microporous AlP04-5 fibers by using micro-emulsion droplets as the templates. The surfactant cetylpyridinium chloride with the cosurfactant butanol in the ratio 1/2 forms a stable micro-emulsion in the... 

FIGURE 6.13 (A) Viability of RAW 264.7 macrophages treated with different SLN formulations compared with cells treated with pure medium (100% viability). Viability is related to the total surfactant concentration in the cell culture medium and was quantified by an MTT assay. All SLN contained 10% Dynasan 114 and 1% of different surfactants (the anionic surfactants sodium cholate [NaCh] or lecithin [S75] or the cationic surfactant cetylpyridinium chloride [CPC]). (B) Viability of RAW 264.7 macrophages treated with different surfactant solutions (the anionic surfactants sodium cholate [NaCh] or lecithin [S75] or the cationic cetylpyridinium chloride [CPC]) compared to cells treated with pure medium (100% viability). Viability is related to the total surfactant concentration in the cell culture medium and was quantified by an MTT assay. 

An example of micellar oxidahon is a biomimetic system of cytochrome P450 investigated by Monh et al. [12], who foimd in the epoxidahon of styrene with NaOCl a significant influence of the type of surfactant cetylpyridinium chloride promoted the reachon more than cetyltrimethylammonium bromide. One explanahon could be a specific noncovalent interachon between catalyst, substrate and surfactant. 

Abezgauz L, Kuperkar K, Hassan PA, Ramon O, Bahadur P, Danino D (2010) Effect of Hofineister anions on micelUzation and micellar growth of the surfactant cetylpyridinium chloride. J CoU InterfSci 342 83-92... 

FIGURE 6.9 Emission spectra of 104 in different surfactant solutions (0.5 mg polymer in phosphate-buffered saline (PBS), 10% w/v surfactant, 385 nm, 25°C) PBS, no surfactant cetylpyridinium chloride (CPC) Triton X-100 (160 mM) Tween 20 (81 mM) and Brij 35 (82 mM). The emission spectra were normalized so that the emission maxima intensities of all the samples are identical. (From Lavigne, J.J., et al., Macromolecules, 36, 7409, 2003. With permission.)... 

Zn Xylenol orange pH 5-6 580 nm Surfactant cetylpyridinium chloride 1 2 4 Dermal ointments... 

Liquid ordered-phase bilayers were formed when mixing a cationic surfactant (cetylpyridinium chloride, CPQ and sterol in a 30/70 molar ratio. 

Spec determination in the presence of cationic surfactant cetylpyridinium chloride... 

Spec determination by use of 2-(5-bromo-2-pyridylazo)-5-diethyl aminophenol in the presence of cationic surfactant cetylpyridinium chloride Enzymatic determination by use of carbonic anhydrase after removing zinc by dialysis against dipicolinic acid... 

W-band EPR was also recently used to help obtain accurate values for the rigid-limit g matrix and nitrogen hyperfine tensor for a spin probe (abbreviated HTAB) in a multi-frequency study of the adsorption and aggregation of the surfactants cetylpyridinium chloride and and cetylpyridinium salicylate on silica surfaces.Polarities and local viscosities (determined from the dynamics of the spin probe) were then deduced. 

Other methods that enable more than two subclasses of cationic surfactants to be separated were proposed by Choi et al. (1997) and Okumura (1992). Six cationic surfactants (cetylpyridinium chloride, Cis and Cig trimelhylammonium chloride, behenyllrimethylam-monium chloride, benzalkonium chloride and benzyldimethylcetylammonium chloride) were separated by Choi et al. using an octadecylsilica column, with an acetonittile/HCl solution as a mobile phase and UV detection, except in the case of cetylpyridinium chloride and Ci5 trimethylammonium. In the case of these last compounds, they were quantified using both UV and suppressed conductivity detector in series. Analytical recovery values from a hair-treatment cream and hair rinse were good. The method proposed by Okumura enabled C15 ig-trimethylammonium and benzyldimethylammoniun, cetylpyridinium chloride and distearyldimethylammonium to be determined by reversed-phase LC at acid pH using a RI detector in shampoos and rinses. 

The addition of the cationic surfactant cetylpyridinium chloride (CPC) to aqueous dispersions ofpolyNIPAM-co-AAc microgel particles leads to absorption of the CPC into the microgel particles [35]. Uptake of the surfactant depends on two distinct attractive interactions between the surfactant molecules and the microgel particles ... 

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