Agilent Manuals

This application note describes a method to separate organic acids by ion suppression chromatography (ISC) using reversed-phase liquid chromatography columns and diode array detection. Experiments were performed using a new ZORBAX SB Aq column that successfully separated organic acids. Two standard mixtures of organic acids and a number of soft drinks and wines were analyzed.

Off-line multidimensional LC/MS can provide high resolution mass spectra, and improve protein identification

This Application Note describes a method for increasing the resolution of complex proteome samples by using two-dimensional offline LC/MS. The method applies a continuous salt gradient in the first separation dimension, which can significantly increase the number of identified proteins from complex samples due to higher chromatographic resolution compared to stepwise elution. In addition, the method offers high flexibility for the investigator since micro fractions of the first dimension can be stored, re-analyzed or chemically modified prior to further analysis. To achieve optimal resolution, the applied 2D LC method strongly requires optimization of the two separation dimensions. Especially elution gradients, analysis time, stationary phase material, and column dimension need to be designed and assembled adequately to attain a considerable increase in overall peak capacity. This Application Note shows data which influences the variables and components. It can serve as a guideline for the investigator to adapt his separation method for a specific proteome sample in order to achieve maximum peptide sequence information by MS/MS analysis. This will result in a maximum of identified proteins after a database search.

This Application Note demonstrates the Agilent Nanoflow Proteomics Solution system1) as a powerful tool for analysis of proteomics samples. Using the approach of cation exchange, sample enrichment, reversed phase chromatography and nanospray ion trap mass spectrometry with subsequent database search, all of ten proteins were identified from a tryptic digestion model mixture and hundreds of proteins from a complex E. coli cell lysate.

A variety of heat-shock proteins (HSPs) were identified in E. coli grown under heat-shock conditions using Agilent Nanoflow Proteomics Solution.

This Application Note describes an improved method for protein identification with two-dimensional nano LC/MS, which utilizes the elution of digest peptides from a strong cation exchange column by an injected salt step gradient of increasing salt concentration with a subsequent reversed phase separation. However, in this approach the ion exchange chromatography does not produce its full performance. To improve the SCX chromatography performance a new method was developed, which works with a semi-continuous pumped salt gradient. This Application Note describes the improved method for two-dimensional nano LC/MS. To show the full performance of the method a complex tryptic digest of the yeast proteome was analyzed. The results obtained with the developed method are compared to the formerly used injection method as well as to an off-line 2D LC method.

This application note describes the use of the Agilent RNA 6000 Pico assay for the assessment of genomic DNA contamination in total RNA isolated from embryonic kidney cells using laser capture microdissection (LCM). Integrity and relative concentration of total RNA were analyzed using the Agilent 2100 bioanalyzer and the RNA 6000 Pico assay. An unexpected peak between the 18S and 28S ribosomal RNA peaks was observed and unambiguously proven, by DNase digestion and genomic DNA spike-in experiments, to be caused by genomic DNA contamination. A simple on-column DNase digestion method is suggested to eliminate contaminating genomic DNA from total RNA samples obtained by LCM, fluorescent-activated cell sorting (FACS), or manual dissection.

The Agilent 1100 Series micro fraction collector is a high-performance solution for processing complex samples in applications such as proteomics, metabolomics, natural product research, and library generation. This Application Note describes the field of application for the Agilent 1100 Series micro fraction collector and discusses the features and software control of this device. In addition, the main modules of the micro fraction collection system are also discussed.

This document introduces the importance of Agilent 2100 bioanalyzer in mRNA sample quality assessment, and provides detailed usage methods and precautions.

This study investigated the comparison of USP-L10 and USP-L7 columns for dissolution and assay testing of norethindrone/mestranol tablets. The results showed that the USP-L10 column provided better peak separation for dissolution testing, while the USP-L7 column provided higher recovery for assay testing.

This document introduces the application of the Agilent ZORBAX Eclipse XDB-CN column, which can be used to analyze complex mixtures containing both polar and nonpolar components, such as pesticide mixtures.

This document describes the method for using the Agilent 2100 bioanalyzer to perform flow cytometric analysis of a limited number of cells.

The document demonstrates the improved liquid chromatography analysis of complex biological fluids using fine particle columns by comparing two columns of different lengths and particle sizes on the analysis of a tryptic digest of human serum albumin (HSA). The columns provide better resolution and comparable sensitivity to 150-mm columns, but in one-sixth the time.

ZORBAX Poroshell 300Extend-C18 is a high-pH stable column for LC/MS applications that can improve signal-to-noise ratio