Chromatography loading samples

In all modes of chromatography, high sample loads distort peak shapes and cause an overall decrease in efficiency due to column overload. Sample loads may be increased by using organic solvents to enhance the solubility of the sample or by using higher column temperatures to lower the viscosity of... 

The practice of hydrophobic interaction chromatography is not unlike that of ion-exchange chromatography large sample volumes can be loaded the composition of the sample solution should correspond to that of the column equilibration buffer after loading, the column should be washed with equilibration buffer and the volume of the gradient should not exceed 10 times the column volume. 

Foam Countercurrent Chromatography Batch Sample Loading... 

Chromatography Load the sample onto the column in a buffer that permits an optimal binding between derivatized matrix and the sought-after protein, according to pH, ion strength, and so on. Allow them enough time to bind. Use prior binding assays to estimate the conditions. 

Purification procedure In step 5 (above) the pellet is washed with buffer A without addition of NH4CI in step 10 (above) the pfRNAP elutes at KCl concentration around 390 mM (Fig. lb) in step 11 (above) the pfRNAP elutes at KCl concentration around 470 mM. After size exclusion chromatography the sample is diluted threefold with buffer A and loaded at a flow rate of 2 ml/min onto a Mono Q HR 10/10 column (Pharmacia) equilibrated with buffer A. The column is washed with 100 ml of buffer A and developed with a 160-ml linear gradient from buffer A to buffer... 

A = Load sample B = Buffer wash C = Gradient start Fig. 6-7. Column chromatography of hen egg-white proteins on (a) DE92 and (b) DE52 using 0.025 M-Tris/HCl buffer, pH 7.5 at laboratory scale (1.5 cm i.d.xl5.5cm) at flow rates of 2mL min. ... 

PSS SEC column dimensions were chosen to allow easy scaling of chromatography conditions without the need to optimize separations for each column dimension separately. The volume flow rate and the sample load can be calcu-... 

Heat and reflux a 5-g portion of soil sample with 50 mL of methanol-phosphate buffer (pH 7)-water (15 7 28, v/v/v) solvent mixture in a round-bottom flask for 1 h. After cooling, transfer a 10-mL portion of the supernatant to a test-tube and mix with 11 mL of 0.02M H3PO4 solution. Load this solution on to a silica-based SPE cartridge (Analytichem International Clin-Elut 1020) at a flow rate of 1-2 drops per second. Discard this fraction. Elute the analytes with 30 mL of dichloromethane. Concentrate the eluate to dryness with air in a water-bath at a temperature of 40 °C (do not use vacuum). Dissolve the residues in 5mL of HPLC injection solution [900 mL of water - - 50 mL of phosphate buffer (pH 7) 4-50 mL of ACN 4-4 g of TBABr]. Pinal analysis is performed using liquid chromatography/ultraviolet detection (LC/UV) with a three-column switching system. 

Fast chromatography involves the use of narrow-bore columns (typically 0.1-mm i.d.) that will require higher inlet pressures compared with the conventional wide-bore capillary columns. These columns require detectors and computing systems capable of fast data acquisition. The main disadvantage is a much-reduced sample loading capacity. Advances in GC column technology, along with many of the GC-related techniques discussed below, were recently reviewed by Eiceman et... 

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