Agilent Manuals

A method for the determination of low ppm and trace level organophosphorus pesticides residues in apple extract using Agilent J&W DB-35ms Ultra Inert GC Column for GC/MS/FPD

This application note details a quick and effective analytical method for the determination of low and trace level polycyclic aromatic hydrocarbons (PAHs) in fish samples as an alternative to procedures involving more time consuming and complex techniques. A simplified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method with dispersive solid phase extraction (dSPE) provided sufficient sample matrix cleanup while preserving low level analyte detection. A pressure controlled tee was installed post column to implement the use of automated backflush to diminish residual sample carryover and reduce instrument cycle times. The Agilent J&W DB-5ms Ultra Inert (UI) 20 m × 0.18 mm , 0.18 µm column effectively resolved the 16 targeted PAHs. A GC/MS method employing selective ion monitoring (SIM) was calibrated at the 10, 25, 50, 100, 250, 500, and 1000 ng/mL PAH levels, yielding excellent linearity and reproducibility. The spiked levels for recovery determinations were 25, 250, and 500 ng/mL. Recoveries ranged from 80% and 139% with RSD below 6%.

Using the AOAC buffered extraction method followed by the use of the Universal Dispersive SPE method for preparing lettuce and apple samples for residue analysis by GC/MS

This application note describes a simple and rapid extraction procedure for pesticide residues in lemon essential oils. The method uses Agilent Bond Elut QuEChERS extraction and modified dispersive SPE coupled with GC/MS.

This application note describes a method for analyzing 20 contract laboratory protocol (CLP) pesticides in olive oil using an Agilent GC-µECD system. A QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) with dispersive solid phase extraction (dSPE) procedure cleaned the sample prior to analysis. A dual µECD and dual capillary GC column approach accomplished simultaneous primary and confirmatory analysis. The primary column, an Agilent J&W DB-35ms 30 m × 0.25 mm × 0.25 µm and a confirmatory column, an Agilent J&W DB-XLB 30 m × 0.25 mm × 0.50 µm effectively resolved all 20 CLP pesticides. An unpurged two-way capillary flow technology splitter divided the flow from a single injection port to the two analytical GC columns. Endosulfan sulfate and endosulfan 1 were present in the olive oil sample.

An HPLC-Florescence Detection (FLD) method was developed and validated for the determination of sixteen polycyclic aromatic hydrocarbons (PAHs) in fish fillets. The method employs a quick, easy, cheap, effective, rugged and safe (QuEChERS) multiresidue sample preparation procedure adopted from the Association of Analytical Communities (AOAC) Official method 2007.01 for extraction and cleanup. The analytes were separated on an Agilent ZORBAX Eclipse PAH HPLC column (4.6 mm × 50 mm, 1.8 µm) by gradient elution with a binary system of acetonitrile - water and subse- quent fluorescence detection set at appropriate excitation and emission wavelengths. The analyte recoveries ranged from 83.4% to 101% with relative standard deviations ranging from 0.6 to 1.9% at three different fortification levels. The limits of detection and quantification ranged from 0.04 to 0.84 and 0.1 to 2.80 ng/g, respectively.

A method for determining sulfonamide residues in chicken muscle using Agilent Bond Elut QuEChERS AOAC Kit and HPLC-FLD

The qualitative and quantitative analysis of pesticides at trace levels in baby food matrices using UHPLC and triple quadrupole MS is demonstrated. Sample preparation is performed using an Agilent Bond Elut QuEChERS kit for extraction and dispersive SPE. The extracts are analyzed by LC/MS/MS on an Agilent 1290 Infinity LC system coupled to an Agilent 6460 triple quadrupole LC/MS using Dynamic MRM. The method and extraction performance were evaluated in terms of repeatability, linearity and sensitivity. Moreover the influence of the additional dispersive SPE cleanup was investigated. Detection limits were between 500 ng/kg and 10 ng/kg (ppt), which is much lower than the maximum residue level (MRL) of 10 µg/kg (ppb) imposed by the European Union.

This application note describes the use of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) EN sample preparation approach for extraction and cleanup of 13-pesticide residues representing various classes in spinach.

This application note describes the use of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) AOAC sample preparation approach for the extraction and cleanup of 13 pesticide residues representing various pesticide classes in spinach. The method involves initial extraction in a buffered aqueous/acetonitrile system, an extraction/partitioning step after the addition of salt, and a cleanup step using dispersive solid-phase extraction (dispersive SPE). A modified method with the addition of toluene was employed to address the significant loss of planar pesticides caused by graphitized carbon black (GCB) in dispersive SPE. The presence of the target pesticides in the spinach extracts were then determined by liquid chromatography coupled to an electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) operating in positive ion multiple reaction monitoring (MRM) mode. The method was validated in terms of recovery and reproducibility for all of the analytes of interest, with a 5 ng/g limit of quantitation (LOQ) for pesticides in spinach. The mean recoveries ranged between 64% and 108% (average of 91.9%), with RSD.

This application note describes the combination of mass spectrometry and evaporative light scattering detection as a powerful tool for the analysis of pharmaceuticals. An Agilent 500 Ion Trap MS was coupled to an Agilent 385-ELSD Evaporative Light Scattering Detector for quantification of Haloperidol and its metabolites, Diazepam and Verapamil, and Ibuprofen and ß-cyclodextrin. Mass spectrometry is highly sensitive and widely used as an information rich detector, but it is not universal and some analytes do not ionize well using standard ion sources. This problem can be overcome by coupling to another kind of detector such as an evaporative light scattering detector, which has many advantages over refractive index and ultraviolet detectors.

Application Note: Sensitive analysis of parabens using HPLC with evaporative light scattering detection at subambient temperatures

This Application Note describes how the Agilent 380-ELSD Evaporative Light Scattering Detector was used to analyze herbicides at low temperature. The detector is designed to evaporate highly aqueous mobile phases at ambient temperature, providing a solution for detecting thermally sensitive compounds.

This Application Note demonstrates that the combination of HPLC with the Agilent 385-ELSD Evaporative Light Scattering Detector provides a better alternative for the sensitive analysis of polar lipids. Evaporative light scattering detection is universal and not dependent on the optical properties of the compound, making it ideal for analysis of lipids such as cholesterol and phosphatidylcholine that have very poor UV chromophores. ELS detection recognizes any compound that is less volatile than the mobile phase. This makes ELS detection fully compatible with HPLC elution gradients. ELS detection also eliminates the need for pre-analysis derivatization to enhance UV absorbance, facilitating rapid determination of lipids in complex matrices.

This application note describes the use of LC(IC)-ICP-MS for low-level speciation analysis of Cr(III) and Cr(VI).