HPLC Application Note Index

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On-Line Solid-Phase Extraction;

Key Words: Phenoxyacid Herbicides, Bentazone, Solid Phase Extraction, 9200 Prospekt

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Description: A Varian LC-Diode Array System was interfaced to a mass spectrometer through either a high flow electrospray interface or an atmospheric pressure chemical ionization interface. This system was used to verify the purity and chemical structure of an x-ray contrast agent

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Description: 121 drugs were identified in postmortem blood extracts by HPLC with diode array detection and PolyView Purity Parameters

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Application of Multicomponent Analysis to HPLC Diode Array Detection for the Quantitation of Partially Resolved Peaks
Key Words: Multicomponent Analysis, Quantitation, Diode Array Detection, Chromatographic Resolution, Paraquat, Diquat, PolyView, US EPA Method 549

Description: The official EPA chromatographic method for Paraquat and Diquat (two herbicides) does not fully resolve the compounds. The method requires dual wavelength detection, but when one compound is 10 times greater than the other, this method gives up to a 50% error in the amount calculated. MCA is able to give result accuracy within 4% for all mixtures

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Application of Multicomponent Analysis to HPLC Diode Array Detection for Quantitation of Unresolved Components
Key Words: Multicomponent Analysis, Quantitation, Diode Array Detection, Polyview, Chromatographic Resolution, Sunscreens

Description: Four cosmetic agents in sun screens were separated with a method which did not fully resolve the individual components. PolyView with Multicomponent Analysis (MCA) produced quantitative results with accuracy of better than 97% and precisions of less than 1%, even for completely fused peaks.

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Identification and Quantitation of Herbicides and Pesticides in Water by LC & Diode Array Detector
Key Words: Pesticides, Herbicides, Triazines, Phenylurea Herbicides, Diode Array Detector, Library Search, Purity Parameters, HPLC, Empore, Solid Phase Extraction, Environmental;

Description: Pesticides and Herbicides can be found in ground water and drinking water. Sample Prep using Empore disks and gradient analysis with diode array detection provide automatic analysis, quantitation and peak identity confirmation through automated library searches using PolyView software.

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Identification of Polynuclear Aromatic Hydrocarbons in a Complex Matrix w/ Diode Array Detection
Key Words: Polynuclear Aromatic Hydrocarbons, PAHs (PNAs), Diode Array Detectors, Compound Identity, EPA 610, Waste Water, PolyView, Polychrom;

Description: Diode array detection is used to confirm the identity of PAHs after separation on three different environmental specialty columns. Specialty columns make it easy to get started in environmental analysis. The DAD with PolyView software provide peak identity confirmation.

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Description: Polynuclear Aromatic Hydrocarbons (PAHs) can be detected by either UV detection of 254nm using EPA Method 610 or 550.1, by time programmed wavelength changes which enhance sensitivity up to 35 times, or by fluorescence detection which can enhance sensitivity up to 100 times.

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Description: Solid phase extraction is used to extract Tobramycin from plasma using Bond Elute cartridges. In order for the extraction to work, the drug is derivitized with OPA to make it less polar and, therefore, easier to separate from serum and to provide enhanced sensitivity.

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Description: Tobramycin is a pharmaceutical which has very low UV absorbance above 205nm making detection difficult, and is very polar minimizing its retention on a reverse phase column. Derivitization of Tobramycin with OPA gives excellent reverse phase retention and 1 picomole detection sensitivity with fluorescence detection. The detrivitization, separation and detection are fully automated using the 9100 AutoSampler, 9070 fluorescence detector, the 9010 and the Star Workstation.

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The Analysis of Milk Sugars with a Modern Refractive Index Detector and a Carbohydrate Column
Key Words: Sugars, Refractive Index Detection, Lactose, Glucose, Galactose, Carbohydrate Column;

Description: Sugars are a common analysis and the appropriate method can depend on a number of factors for the case of sugars in lactose reduced milk a speciality carbohydrate column provides excellent resolution and the refractive index provides adequate sensitivity.

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Chiral Separation and Detection Enhancement of Propranolol Using Automated Precolumn Derivatization
Key Words: Pharmaceuticals, Propranolol, FLEC, AutoMix, Chiral, Enantiomers, Diastereomers, Racemic Mixtures, Detection Enhancement, Fluorescence, Precolumn Derivatization

Description: Propranolol is a pharmaceutical that is chiral and has low UV absorptivity. Chiral separation and detection enhancement are achieved by precolumn derivatization with FLEC, a chiral and fluorescent derivatization reagent. Automation is achieved by using the 9095 AutoSampler.

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Description: AminoTag is an automated Star HPLC based Precolumn amino acid derivatization technique with the reagent, FMOC (Fluorenylmethyl-Chloroformate).

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Tschida

Aamodt

Description: Describes an automated, single point control system for Carbamate pesticide determination. Utilizes advanced safety and stability features of the Pickering postcolumn reaction system using OPA (o-Phthalaldehyde) derivatization.

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