Hydrodynamic chromatography HDC

Hydrodynamic chromatography is a chromatographic technique for measuring the particle-size distributions of polymer lattices of approximately 0.1-1 pm and inorganic colloids in the 0.01-40 pm range. 

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Hydrodynamic chromatography (HdC) is a relatively new technique, especially in molecular weight separation. It was first investigated in 1969 by DiMarzio and Guttman (1,2) and was called separation by flow (3,4). Small started calling it hydrodynamic chromatography in 1974 (5). The application of this technique was first concerned with the separation of particle size. Prud homme applied it to the molecular weight separation of macromolecules in 1982 (6). 

The publications on a technique of particle size measurement called hydrodynamic chromatography (HDC) by Hamish Small, ... 

Separation by size can occur even on a nonporous material, as the flow in the center of a flow channel is faster than that near the walls. Since large molecules are excluded from the wall regions, they tend to travel in the faster flow down the flow channel center, a phenomenon known as hydrodynamic chromatography (HDC).5658 As discussed in Chapter 1, a mixed-mode form of HDC called "slalom chromatography" has found application in DNA analysis. HDC, however, is far less efficient as a separation process than GPC. 

Hydrodynamic chromatography (HDC), in particle size measurement, 13 146 Hydrodynamic flow, in microfluidics, 26 962... 

Sedimentation techniques are also utilized for particle size distribution for particles on the order of 0.1-50 pm. Capillary hydrodynamic chromatography (HDC) gives particle size distributions for particles of about 0.005-0.7 pm. 

In the earlier publications (1,2) it was shown how hydrodynamic chromatography (HDC) could be applied in the study of polymer latexes to determine particle-size. An improved technique for the HDC was developed which utilized higher efficiency and resolving power columns to significantly reduce the analysis time (3). A high speed integrated computer was included in this improvement so that both particle-size and particle-size distribution of latexes could be quantified in the relatively short period of time. This high speed computerized version of the HDC has been used extensively for measurements on the final latex. 

Commercially available fractionation methods include hydrodynamic chromatography (HDC), field flow fractionation (FFF) and disc centrifugation (DSC). One advantage of fractionation methods over nonfractionation methods is that the particles are separated physically according to size, prior to detection, which allows much higher resolution in determining the size distribution [40]. 

Hydrodynamic chromatography (HDC) offers a means of obtaining size information on colloidal particles in suspension with the same ease that is characteristic of chromatographic methods for size analysis of molecules in solution. 

Koehler and Provder [317] sized monodisperse PMMA latexes with a range of instruments Disc centrifugal sedimentation (DCP), sedimentation field flow fractionation (SFFF), hydrodynamic chromatography (HDC), photon correlation spectroscopy (PCS), turbidimetry and transmission electron microscopy (TEM). TEM gave the smallest sizes, DCP and SFFF were in fair agreement in the center and PCS the highest sizes. 

In the first approximation, the column packed with small particles can be considered an array of capillaries. Hydrodynamic processes augment the exclusion based separation (see section 11.7.2, Retention Mechanisms and Accompanying Processes in SEC) and form the ground of a liquid chromatography-like method called hydrodynamic chromatography, HDC. HDC found application in separation of veiy large macromolecules, particles and dispersions. Its separation selectivity is rather low and it was partially substituted by the group of methods termed fieldflow fractionation (see seetion 11.3.3, Molar Mass Dispersity). 

C.A. Silebi, Mathematical Modelling of Hydrodynamic Chromatography (HDC), unpubl. Ph.D. thesis, Lehigh University, Bethlehem, PA (1977). 

There are several other techniques complementary to DLS that allow the determination of the diffusion coefficient of supramolecular systems in dilute solution. These include Taylor dispersion analysis (TDA)," hydrodynamic chromatography (HDC), and size exclusion chromatography... 

Hydrodynamic chromatography (HDC) has the potential to yield rapid high-resolution separations of polymers according to molar mass. This potential has been demonstrated for packed-column HDC by Stegeman (1994), who has shown some fast and efficient separations on columns packed with very small particles (typically below 2 tm diameter). HDC is easiest and most attractive for the separation of very large molecules and small... 

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