Microflow liquid chromatography coupled to mass spectrometry--an approach to significantly increase sensitivity, decrease matrix effects, and reduce organic solvent usage in pesticide residue analysis.

This manuscript reports a new pesticide residue analysis method employing a microflow-liquid chromatography system coupled to a triple quadrupole mass spectrometer (microflow-LC-ESI-QqQ-MS). This uses an electrospray ionization source with a narrow tip emitter to generate smaller droplets. A validation study was undertaken to establish performance characteristics for this new approach on 90 pesticide residues, including their degradation products, in three commodities (tomato, pepper, and orange).

Trace analysis of herbicides in wastewaters by a dispersive liquid-liquid microextraction approach and liquid chromatography with quadrupole linear ion trap mass spectrometry: evaluation of green parameters.

An analytical method for determining phenylureas (monuron, isoproturon, diuron, linuron and neburon) and propanil herbicides in wastewater has been developed and validated, and the most significant parameters were compared with the corresponding ones found in the literature, thus showing the method performance. The method involves pre-concentration by a simple, rapid, sensitive and low environmental toxicity temperature-controlled ionic liquid dispersive liquid-liquid microextraction procedure. The herbicides were identified and determined by liquid chromatography with a hybrid triple quadrupole linear ion trap mass spectrometer.

Identification and quantification of poly(amidoamine) PAMAM dendrimers of generations 0 to 3 by liquid chromatography/hybrid quadrupole time-of-flight mass spectrometry in aqueous medium.

Rationale: Poly(amidoamine) PAMAM dendrimers are highly water soluble and are used as flexible scaffolding or nanocontainers to conjugate, complex or encapsulate therapeutic drugs to overcome intrinsically weak characteristics such as solubilization in aqueous medium. To provide a reliable method for the quantitation of PAMAM dendrimers in aqueous medium, we report here a validation study which was developed in a complex wastewater matrix to evaluate the matrix effect in the electrospray ionization (ESI) source.

Methods: PAMAM dendrimers (generations G0 to G3) were identified and quantitated in aqueous medium using liquid chromatography interfaced to a hybrid quadrupole/time-of-flight mass analyzer.