Preparation of chromatographic

The main problem using planar methods is the difficulty in detection and collection of fractions among other less critical problems, such as homogeneous preparation of chromatographic media. However, the detection problem exists also for the coupled-column methods, mainly because of fraction dilution by each stage in a multidimensional separation system. Another aspect is the adjustment of chromatographic time bases between the different dimensions so that first-dimension peaks may be sampled an adequate number of times by the next dimension separation system. This aspect has been recently studied in detail (Murphy et al., 1998), and is covered in detail in Chapters 2 and 6. 

This test is described on pp 5-rl7 of Ref 14 Preparation of Chromatographic Column. 

Bromelain. Although several investigators have reported the preparation of chromatographically pure stem bromelain (37, 38), there is some... 

Essential oils - General guidance on chromatographic profiles - Part 1 Preparation of chromatographic profiles for presentation in standards... 

These developments have been fuelled in part by the apparently unrelenting increase in microcomputing power, bringing with it improved control and data acquisition and processing capabilities and partly by the improved technologies for the preparation of chromatographic media and packings in GC and LC, for example, chiral stationary phases, bonded phase capillary GC and narrow bore HPLC. 

Preparation of Chromatographic Supports. Styrene-divinylbenzene copolymers (Bio-Beads SX2, 200-400 mesh) from BioRad, France, were first chlorosulfonated (17). Further reaction of the chloro-... 

One consequence of the uniform binding site distribution and high capacity of these polymers is that they may be rather better suited to the preparation of chromatographic (HPLC) stationary phases than noncovalently imprinted materials. In fact this was the conclusion arrived at by Hwang and Lee [15], who compared the chromatographic performance of cholesterol-imprinted polymers prepared by the semi-covalent (carbonate spacer) method with noncovalent MIPs incorporating... 

Because none of these morphologies is perfect for the preparation of chromatographic separation media, numerous hybrid materials have also been developed in an attempt to preserve advantages of both gels and macroporous materials while trying to avoid their drawbacks. In addition, nonporous micro-pellicular beads are available for the rapid separation of biopolymers. 

Figure 10 Preparation of chromatographic plates for preparative OPLC. (a) Linear separation, (b) Anticircular separation, (c) Circular separation. (1, polymer suspension 2. inlet channel/hole 3, outlet channel/hole.)...

Wulff G, Vesper W. Preparation of chromatographic sorbents with chiral cavities for racemic resolution. J Chromatogr 1978 167 171-186. 

Preparation of chromatographic column. Plug the bottom of the tube with cotton wool and mount in a vertical position. 

Preparation of chromatographic column Triturate 5 g of Celite 545 with 25 ml of 2,2,4-trimethylpentane and 2 ml of polyethylene glycol 600 until a thick, uniform mixture is obtained. Transfer to a chromatographic tube, 10 mm in diameter, fitted with a fritted disc of coarse porosity at its lower end, and pack down firmly. 

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