Solubilization agents Triton

Anionic surfactants (SDS and deoxycholate) are more effective solubilizing agents at higher concentration than nonionic surfactants (Lubrol, Triton)... 

Figure 3. Membrane skeletal association of FPR. Neutrophils were solubilized with Triton X-100 and the extracts were spun over sucrose density gradients. The distribution of photoaffinity labeled FPR was analyzed on SDS-polyacrylamide gels with a Phosphor Imager. Percent receptors that are coupled to the membrane skeleton are shown for responsive control cells (C), partially (PD) and fully (FD) desensitized neutrophils. In addition, values are shown for cells after solubilization in the presence of agents causing depolymerizaiton of actin filaments, like KCl, p-chloromercuriphenylsulfonic acid (pCMPS) or DNAse I. For experimental details see [44].

In Table 2, the values of n are presented for the intact membrane, solubilized membrane, reaggregated material and Triton X-100 solubilized reaggregated material from animals fed corn oil supplemented diet and fat-free diet, respectively. As it can be observed, the value of n is around 1.6 for all the enzyme preparations from the fat sufficient animals. For the preparations from the fat deficient animals instead it is in the order of 1.0 in the case of intact membrane and reaggregation membrane like material, and around 1.6 for the solubilized preparations. Similar results were obtained with the other solubilizing agents (Martinez de Melian et al., 1976). Further evidence on the role played by the membrane was obtained when the acetylcholinesterase band from the gel electrophoresis of solubilized acetylcholinesterase from fat sufficient animals was eluted, mixed with lipid extracted from red cell membranes of rat fed a fat-free diet, and diffused against buffer. A value of n=1.0, which corresponds to that of the intact membrane from the deficient... 

Inorganic substances Uke small metal clusters, metal oxides etc. may also be deposited on the surface of single or bundled carbon nanotubes. It is possible, for instance, to decorate multiwalled nanotubes with nanoparticulate oxides of zinc or magnesium. To this end, a surfactant-mediated dispersion of MWNT is solubilized in cyclohexane with Triton X-114 as a surface-active agent to obtain a water/ oil emulsion. Aqueous solutions of the respective metal acetates are added afterward and are then found in the aqueous portion of the emulsion. Subsequently increasing the pH value to about 9.5 causes a precipitation of the metal hydroxides that deposit on the nanotube surface in the shape of hollow spheres. Final calcination at 450 °C transforms these hollow particles into the crystalhne metal oxides. Particles measuring about 5 nm or 30-40 nm have been observed for ZnO or MgO, respectively (Figure 3.84b). 

Other binding agents seem to have no effect on channel behavior. Concanavalin A binds to rat liver VDAC in the triton XIOO-solubilized form (4, 43). Antibodies against N. crassa VDAC inhibit VDAC insertion into planar membranes and bind to VDAC crystals in membranes, but do not affect channel behavior (44). These agents may interact with a surface domain on VDAC that does not respond to membrane potentials. 

Solubilization of proteins for radioactivity counting can be also effected by non-specific proteases or by chaotropic agents (guanidinium chloride). In the latter case gel slices are incubated with 1 ml of 6 M guanidinium hydrochloride at 90°C for 12 h. Then, 33% Triton X scintillation fluid is added and samples are counted. Efficiency is 12% for tritiated compounds. 

The electrophorectic patterns of acetylcholinesterase (solubilized by different agents such as Triton X-100 at different concentrations, sodium deoxycholate or ultrasonic irradiation) indicated the presence of multiple enz)nnatic forms, the chemical nature of which are only partially understood. However, the multiple forms for either the enzyme from the sufficient or deficient animals, respectively, were not significantly different (Martinez de Melian et al., 1976). These results are presented in Table 1. A single band of activity in polyacrylamide-gel, independent upon the method employed, can be obtained under controlled and standard conditions. 

---