Agilent Manuals

This paper presents a method for analyzing common aerosol propellants and an alternative blending technique for high concentration standards. The analysis was performed using an Agilent Technologies gas chromatograph configured with an automated 6-port gas sample valve, a split injection inlet, an HP-PLOT Q capillary column, and a thermal conductivity detector. Six methods were configured with six different split ratios to create a six-point calibration curve for each standard. Additionally, a method is provided to dynamically dilute samples when a multipoint calibration is desired across a narrow calibration range from a single standard.

This document describes the optimization of peptide separations using PLRP-S reversed-phase material in acidic and basic conditions by HPLC with ELSD.

This application note describes the use of ion-pair reversed-phase chromatography for the separation of de-protected oligonucleotides, focusing on media and ion-pair requirements.

This document introduces a liquid chromatography technique for analyzing polymers that can detect very small differences in the chemical structures of polymers. This technique uses critical point mobile phases and is more sensitive to small differences in polymer structure than conventional interactive chromatography techniques, making it a more suitable method for these analyses.

1,12-Dodecyldiphosphonic acid is a phosphorous acid, is polar and has surfactant properties. It consists of two polar heads joined by a non-polar, twelve carbon chain. Agilent Technologies, Inc. published a application note to demonstrate how the Agilent ELSD can be used to analyze 1,12-dodecyldiphosphonic acid.

This Application Note describes the reverse-phase HPLC method for the analysis of fatty acids using Agilent HPLC systems.

This application note describes the optimization of an ion suppression reversed phase HPLC method to detect L-ascorbic acid, and use of the method in the quantitative determination of the acid in fruit juice. PLRP-S columns were used in this investigation. PLRP-S is a rigid macroporous styrene/divinylbenzene HPLC phase with outstanding chemical and physical stability, and high surface area. This chemical stability permits the use of low pH eluents and ion suppression reversed phase HPLC.

This paper presents the influence of the silica pore size on the separation, efficiency and capacity of a separation using a number of standard compounds. The study uses a prep to process material, SepTech, which uses ultra pure silica as the base particle and a bonding chemistry to give a high carbon load C18 material. Two pore sizes, a 60Å (ST60 10-C18) and a 150Å (ST150 10- C18) were used. The results show that the silica pore size has a large impact on the separation efficiency, resolution and capacity.

Describes the Agilent PLgel MIXED-D and GPC/SEC application for measuring styrene/isoprene block copolymers.

This application note describes the use of Agilent PLgel columns for the separation of low molecular weight polystyrene standards by gel permeation chromatography.

This document discusses the analysis of polyvinylidene fluoride (PVDF) on Agilent PLgel 10 µm MIXED-B and GPC/SEC. PVDF is an important material with a wide range of uses from non-stick coatings to inert packaging materials. However, PVDF can be difficult to analyze by gel permeation chromatography due to its low solubility in common solvents. This challenge can be overcome by using dimethyl sulfoxide as a solvent, Agilent PLgel MIXED-B columns, and operating the GPC system at elevated temperature with appropriate high temperature sample preparation. In this study, three samples of PVDF were analyzed in dimethyl sulfoxide at 95 °C using the Agilent PL-GPC 220 instrument with two Agilent PLgel 10 µm MIXED-B, 300 × 7.5 mm columns. By operating the GPC system at a flow rate of 1.0 mL/min and heating the samples for 4 hours to dissolve them and reduce the solvent viscosity, satisfactory chromatographic separation was achieved.

This article describes the analysis of dialkyl phthalates using gel permeation chromatography on Agilent PLgel 3 µm columns. The method is suitable for analyzing low molecular weight polymer additives such as dialkyl phthalates.

This document describes the application of HPLC with ELSD for high-resolution analysis of triglycerides in cooking oil. ELSD detection offers higher sensitivity and adaptability compared to RI and UV, enabling the detection of low levels of contaminants. The author used a PLRP-S 100Å column and Agilent's ELSD detector for the analysis, and presented a chromatogram of unadulterated cooking oil.

This application note describes the conditions and results for the separation of Epikote 828 and 1001 using an Agilent HPLC system.

This article describes the analysis of polybutadiene terephthalate (PBT) resin. PBT resins are widely used in various applications due to their excellent toughness and resistance to damage. The molecular weight distribution is a key measure for assessing resin degradation and estimating the mechanical strength of the final product. The analysis of PBT was performed using gel permeation chromatography (GPC) in the polar organic solvent 1,1,1,3,3,3-hexafluoroisopropanol (HFIP). The article discusses the use of Agilent PL HFIPgel columns for the analysis at 40°C, with detection using differential refractive index and viscometry. GPC coupled with a molecular weight sensitive viscometer allows for the calculation of molecular weights based on hydrodynamic properties.