Membrane chromatographic system stationary phase

Amorphous silicas play an important role in many different fields, since siliceous materials are used as adsorbents, catalysts, nanomaterial supports, chromatographic stationary phases, in ultrafiltration membrane synthesis, and other large-surface, and porosity-related applications [16,150-156], The common factor linking the different forms of silica are the tetrahedral silicon-oxygen blocks if the tetrahedra are randomly packed, with a nonperiodic structure, various forms of amorphous silica result [16]. This random association of tetrahedra shapes the complexity of the nanoscale and mesoscale morphologies of amorphous silica pore systems. Any porous medium can be described as a three-dimensional arrangement of matter and empty space where matter and empty space are divided by an interface, which in the case of amorphous silica have a virtually unlimited complexity [158],... 

Both methods use a low-capacity cation exchanger as a stationary phase and a dilute mineral acid such as hydrochloric or nitric acid as a mobile phase. Although stationary phases and eluents have changed over the years, the principal difference between the methods is the same up to the present day. For his hypothetical experiments. Small kept constant the volume of the stationary phase, the ion-exchange capacity of the separator colunm, the selectivity coefficients for sodium and potassium relative to the hydronium ion, and the injection volume. With these values and the known acid concentration in the mobile phase, it is possible to calculate the elution volumes of sodium and potassium. To further simplify the calculation of the elution profiles, the chromatographic peaks are assumed to be symmetrical, so that they can be described by a Gaussian curve. One can further assume that the membrane-based suppressor system exhibits a very small dead volume and, therefore, subtracts negligibly from the efficiency of the separator column, which is estimated to be 3000 theoretical plates. 

The radioactively labeled proteins of the mitochondrial membranes were separated using an amphipathic chromatographic system The stationary phase of this system is polymethacrylic acid resin, some of the carboxylic groups of which are linked to oleylamine by means of an amide bond (as outlined in Fig. 3). The mobile phase is a solution of the detergents cholate and deoxycholate. Thus, the mobile phase and the resin... 

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