Biomedical subjects

M N Schmuck

Publications and source records attributed to M N Schmuck.

3 recordsLinked to original sources

PubMed1991

Building ruggedness into HPLC quality control procedures.

HPLC methods for protein and peptide analysis are excellent in terms of resolution, selectivity and recovery. They are, however, complex procedures involving multiple parameters including instrumentation, columns and mobile phases that may lead to inter- or intra-laboratory deviations. The factors that contribute to differences in retention, selectivity and sensitivity are discussed, followed by suggestions for eliminating or compensating for the differences.

Chromatography, High Pressure Liquid↗

PubMed1986

Comparison of porous silica packing materials for preparative ion-exchange chromatography.

Although analytical high-performance liquid chromatographic columns have been successfully used for purification of milligram amounts of proteins, they do not appear to be ideal for preparing gram or kilogram quantities because of cost and load capacities. In this paper the development of preparative weak anion-exchange materials is described. These materials possess similar chromatographic characteristics to analytical 5-10 micron materials, yet also have high load capacities. A number of inorganic packings were examined to determine which had the best combination of high load capacity, good resolution, stability, and low cost. When appropriate flow-rates and gradient shapes were used, 30-50 micron materials produced resolution of components of a commercial ovalbumin sample that was comparable to that achieved on a 6-micron material. An amount of 3 g of a protein could be loaded onto a 250 X 21 mm-I.D. column with adequate resolution to separate it from some of its impurities.

Animals↗

PubMed1986

Optimization of preparative hydrophobic interaction chromatographic purification methods.

The chromatographic behavior of five proteins on hydrophobic interaction matrices having six different ligand arms was investigated using gradient elution with ammonium sulfate and ammonium acetate buffers at two pH values. The nature of the mobile phase and/or the ligand chain arm of the matrix was found to have substantial effect on the resolution, retention, and selectivity. Ovalbumin was moderately or highly retained with ammonium sulfate on all columns; however, with ammonium acetate, ovalbumin was not retained on SynChropak Hydroxypropyl and Propyl columns. Chromatographic conditions developed for analytical hydrophobic interaction chromatography columns containing 6.5-micron packings were adapted to preparative columns packed with 30-micron SynChroprep packings for the separation of serum components. Dynamic load capacities were 4-13 mg of ovalbumin per ml of column volume.

Acetates↗