Sensitive and Rapid Determination of Paraquat and Diquat in Tap and Environmental Waters

Instrument Type: UHPLC

Paraquat and diquat are widely used as agriculture herbicides to control crop and aquatic weeds. They ontaminat of drinking and environmental waters and are considered a risk factor for liver, heart, lung, and kidney illnesses. We review pertinent EPA methods for analysis that meet Maximum Contaminant Level Goal (MCLG) of 20 µg/L for diquat in drinking water and EU general rules for pesticides and herbicides in drinking water. We describe more recent work shows an improved method using a new mixed-mode column specifically designed to provide good peak shapes for diquat and paraquat.

Determination of Tetrahydroisohumulones by the BeerNHop Solution with Rapid Separation On-Line SPE

Instrument Type: UHPLC

The BeerNHop solution for high throughput was applied for a direct injection of the Thermo Scientific tetrahydroisohumulones standard. Automated analyte enrichment was done on a Thermo Scientific Hypersil GOLD C8 being used as SPE column. Afterwards, the separation was realized on a Thermo Scientific Hypersil GOLD 1.9 µm column with UV detection at 270 nm. With a total run time of 15 minutes, the method allows easy screening for reduced isohumulones in a beer that is meant to comply with the German purity law.

Sensitive and Rapid Determination of Polycyclic Aromatic Hydrocarbons in Tap Water

Instrument Type: HPLC

This method describes an on-line SPE HPLC method with UV absorbance and fluorescence detections for rapid and sensitive determination of 20 PAHs in tap water. The determination is performed on a Thermo Scientific UltiMate 3000 Dual RSLC system combined with a Thermo Scientific Hypersil Green PAH analytical column. Reduced MDLs for UV and fluorescence detection, enabled by on-line SPE using the Thermo Scientific Dionex Acclaim PA2 column, provide a convenient method for determining these compounds in drinking and environmental waters using HPLC.