Monolithic columns fast gradient separation

Fig. 8. Fast semi-industrial scale separation of a protein mixture using an 80 ml CIM DEAE Tubular Monolithic Column. Conditions Column 80 ml CIM DEAE Tubular Monolithic Column Mobile phase Buffer A 20 mM Tris-HCl buffer, pH 7.4 Buffer B 20 mM Tris-HCl buffer +1 M NaCl, pH 7.4 Gradient 0-100% Buffer B in 30 s Sample 2 mg/ml of myoglobin (peak 1), 6 mg/ml of conalbumin (peak 2) and 8 mg/ml of soybean trypsin inhibitor (peak 3) dissolved in buffer A Flow Rate 400 ml/min Injection volume 1 ml Detection UV at 280 nm...

Extremely rapid RP separations of proteins have been demonstrated on poly(styrene-co-divinylbenzene) monolithic columns. A fast gradient and a flow rate of lOmL/min were used to separate live model proteins in less than 20 s on a 50 X 4.6-mm ID column [53].The same type of monolithic structure has also been prepared in capillary columns of 200 pm ID and showed excellent performance in the identification of proteins by LC-MS through peptide mass fingerprinting and accurate intact molecular mass determination [24]. 

Fig. 2 Separation of test proteins in seconds on a CIM QA disk monolithic column. Conditions— buffer A 20 roM Tris HCl buffer, pH 7.4 buffer B 1 Af NaCl in buffer A, pH 7.4 flow rate 10 ml/min detection UV at 280 nm gradient step gradient at 0%, 20%, and 50% buffer B for 2 sec each sample (1) myoglobin (0.5 mg/ml), (2) conalbumin (1.5 mg/ml), (3) soybean trypsin inhibitor (2 mg/ml) injection volume 20 p,l. Source From Application of compact porous disks for fast separations of biopolymers and in-process control in biotechnology in Anal. Chem. ...

Fig. 14 a, b. Effect of gradient steepness on the very fast separation of polystyrene standards in a molded monolithic poly(styrene-co-divinylbenzene) column (Reprinted with permission from [121]. Copyright 1996 Elsevier). Conditions column, 50 mm x8 mm i.d., mobile phase, linear gradient from 100% methanol to 100% tetrahydrofuran within a 1 min b 12 s, flow rate, 20 ml/min, peaks represent polystyrene standards with molecular weights of 9200,34,000 and 980,000 (order of elution), 3 mg/ml of each standard in tetrahydrofuran, injection volume 20 pi, UV detection, 254 nm... 

Dams et al. [19] determined seven different opium alkaloids and derivatives in seized heroin using fast LC-MS analysis. Analytes were separated in 5 min on a monolithic silica column with a gradient elution system and an optimized flow of 5 mL/min. Detection was carried out using a sonic spray ion source [20] a modified ESI source were ionization is achieved using a nebulizer gas at sonic speed instead of applying an electrical field. 

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