The Column-09-21-2016
Improving Biopharmaceutical Purification Using LFMC
September 21st 2016Biopharmaceutical purification techniques can be slow and cumbersome with poor scalability. A new device using laterally-fed membrane chromatography (LFMC) was developed to address these issues. Raja Ghosh from McMaster University in Hamilton, Ontario, Canada, spoke to The Column about this new device and its potential applications.
Measuring Carbon Tetrachloride Atmospheric Mixing Ratios in the Central Amazon Rainforest
September 21st 2016Carbon tetrachloride (CCl4) is a potent greenhouse gas in the troposphere, while in the stratosphere it contributes to ozone destruction. Global atmospheric models treat anthropogenic industrial processes as the sole source of atmospheric CCl4. However, some evidence suggests that biogenic sources may also contribute. This article describes grab-sampling with analysis by thermal desorption–gas chromatography–mass spectrometry (TD–GC–MS) to assess levels of CCl4 in a Central Amazonian rainforest. We find that ambient air mixing ratios within and above the forest, while agreeing with current equatorial estimates (120 ppt), show diurnal and canopy-height variations that suggest a biogenic source of CCl4, and therefore may be important for closing the gaps in the global atmospheric CCl4 budget.
Trace Perchlorate Determination by Ion Chromatography
September 21st 2016Perchlorate salts are relatively stable, soluble in water, and migrate into groundwater sources causing possible challenges for drinking water suppliers as dissolved perchlorate has been identified to impair normal thyroid function. The development of a sensitive analytical method for perchlorate determination is therefore important to protect public health. This article addresses the validation of ion chromatography with suppressed conductivity detection (IC–CD), applying isocratic elution to analyze perchlorate.
