Controlled porosity glass

The first (] ) employed controlled porosity glass (CPG-10) with formamide containing KCl (0.005 M) as the mobile phase. The... 

Rogalski J, Jozwik E, Hatakka A et al (1995) Immobilization of laccase from Phlebia radiata on controlled porosity glass. J Mol Catal A Enzym 95 99-108... 

From these studies with SynChropak SEC packings and controlled porosity glass, it is concluded that the silica packing contains a population of micropores which are differentially accessible to low molecular weight probes of total permeation volume. It is not known, however, if the microporosity in the 100 and 300A SynChropak SEC packings is the result of the rather wide pore-size distribution and whether all silicas contain micropores. 

Four types of media possess most of these desirable characteristics agarose, polyvinyl, polyacrylamide, and controlled-porosity glass (CPG) beads. Highly porous agarose beads such as Sepharose 4B (Pharmacia) and Bio-Gel A-150 m (Bio-Rad Laboratories) have virtually all of these characteristics and are the most widely used matrices. Polyacrylamide gels such as Bio-Gel P-300 (Bio-Rad) display many of the recommended features however, the porosity is not especially high. 

Presently three media can be considered as potentially useful in affinity chromatographic techniques agarose, polyacrylamide, and controlled porosity glass beads. Of these three, agarose beads are by far the most often used because they possess all the desirable features cited above. The only major disadvantage of agarose is its susceptibility to contraction when denaturant solutions are used for elution. 

Numbers in parentheses indicate NO conversion at wet condition. CPM = controlled porosity glass. 

Controlled porosity glasses (CPGs) as adsorbents, molecular sieves, ion-exchangers and support matericils... 

The making of controlled porosity glasses involves a three-step procedure ... 

The characteristic feature of controlled porosity glasses is a very narrow pore size distribution [2,3,5,16], well seen when compared with silica gel or other porous materials produced by polymerization or by crosslinking of monomers-cf. Fig. 5. 

Investigations of surface free energy (SFE) of controlled porosity glasses and silica gels carried out more recently showed certain similarity in the properties of bare materials and important differences caused by thermal treatment [49-56]. Dispersive interactions expressed as dispersive component of SFE (7 ) and polar interactions expressed as polar component of SFE (7 ) measured by means of hexane and toluene respectively are similar for both materials. The average value of 7 for silica gel equals 35.6 mj/m and for CPG 35.0 mJ/m. The mean values of 7P for silica gel and CPG are 159.8 mj/m and 159.2 mJ/m, respectively. The thermal treatment of both materials leads to a small increase of dispersive interactions and simultaneously causes a significant drop of polar interactions. 

Advertasing Materials about Controlled Porosity Glasses, edited by Electro-Nucleonics, Inc., 386 Passaic Ave., Fairfield, N. J., 07006, USA. 

Dawidowicz, A. et al.. The effect of thermal treatment of controlled porosity glasses (CPGs) on the properties of the electrical double layer at the CPG/electrolyte interface, J. Colloid Interf. Sci., 115, 555, 1987. 

Janusz, W., Dawidowicz. A.L., and Szczypa, J., Surface charge and adsoiption of sodium ions at the controlled porosity glasses/electrolyte interface, 7. Mater. Sci., 26, 4865, 1991. 

Polyacrylamide Controlled-porosity glass Mean pore diameter 3125, 2000, 973, 493,240 and 123 A Column size = 4 ft X 3/8 in ID. Aqueous solution with 0.005 M KCl RI detector 34... 

Polyacrylamide Acrylamide/ sodium acrylate copolymer Dextrans, polystyrene sulfonated Controlled-porosity glass Mean pore diameter 16.4-300 nm Column size 620 mm long 7 mm I.D. Aqueous solution with 0.1 M Na SO, which contained 10 ppm biocide KathonWT RI detector Cubic B-sphne calibration technique 35... 

Dry-packed controlled porosity glass Mean pore diameter 700, 1000 and 3000 A Particle size 200/400 mesh Column size 3.8 in. l.d. 4-6.5 ft long... 

Reaction with periodate-oxidized agarose that had been treated with 1,6-diaminohexane and reduced Reaction with activated forms of silk Reaction with, and glutaraldehyde-linked to, various derivatives of controlled-porosity glass Entrapment in gels of calcium alginate Reaction with agarose cyclic imidocarbonate... 

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