SEPARATION SCIENCE LATEST EDITION 

Determination of Risperidone and 9-hydroxyrisperidone in Human Plasma
A highly sensitive, selective, accurate and precise method for simultaneous quantification of risperidone and 9-hydroxyrisperidone in human plasma was developed. The method was based on electrospray ion trap tandem mass spectrometry in multiple reaction monitoring mode. Risperidone, 9-hydroxyrisperidone and carbamazepine, an internal standard, were extracted from plasma by a single step extraction with ether after the addition of sodium hydroxide and sodium chloride. A 5-μL aliquot of the sample reconstituted in mobile phase was analysed on a C18 column at 30 ˚C with the mobile phase consisting of acetonitrile and ammonium acetate buffer pH 5.5 (35:65 v/v).
 
 
Food Ingredients
The benefits of analysis using triple detection SEC chromatography
The ability to accurately determine the molecular weight distribution and branching characteristics of complex food ingredients is paramount. The performance, and in some cases the safety, of food additives based on polysaccharides depends strongly on their molecular weight and structure. Many polysaccharides used as food ingredients have large molecular sizes, however, and this can present a challenge for characterization.
 
 
Optimisation of Existing Methods for Analysis of Antibiotics in Meat using MS/MS Detection
The accurate detection and analysis of residual antibiotics in meat for human consumption is of critical importance in ensuring strict adherence to regulatory requirements for food safety. This article – the first in a series of features considering the detection of contaminants in meat – describes the optimization of an existing detection methodology that results in increased throughput by 5–10-fold, and more accurate and reproducible results, ensuring the best possible quantitation.
 
 
How to get more analysis out of your GC system?
A common question we get asked by our customers is how they can get a longer column lifetime. This can be from a cost perspective (column price) or from a maintenance perspective (downtime, labour, calibration).



 HPLC SOLUTIONS LATEST EDITIONS 
 

Readers Share In-Line Degasser Experiences

After I wrote an HPLC Solutions article on in-line degassers (#72), I immediately received some reader feedback on a specific failure, which was published in #73. Since that time I have been collecting occasional reports of degasser failures. This week I’d like to share a few of these.
Click here to learn more>>
  
 
 

Column Abuse, 2: Column Storage
A reader asked me if she was in danger of shortening the lifetime of an HPLC column by removing it after each batch of samples and storing it. This also raised the related question about expectations of shorter column lifetimes if the same instrument was used for multiple methods, each with a different column.



 GC SOLUTIONS LATEST EDITIONS 


Calibration Curves – Part 2
This month we cover the internal standard method of GC calibration.The goal of any quantitative analysis is to accurately determine the concentration of target analytes in an original sample. Often, the original sample is not suitable for direct injection into a GC. Some of the reasons samples might need to undergo sample preparation prior to analysis are. Mattew Klee explains more...
 
 
Calibration Curves – Part 1
This month we discuss general approaches to GC response calibration and focus on the simplest; external calibration. The heart of quantitative analysis is proper calibration. By determining the relationship between the magnitude of a peak for a known amount of analyte in a standard, one can then use that relationship (the calibration curve) to estimate the amount of that analyte in a sample of unknown concentration.
 


 MS SOLUTIONS LATEST EDITIONS 
 
NIST 11: What’s New and What Value Does it Offer? Part 4
This installment in the series on NIST 11 is about the Incremental Name Search, replicate spectra, and the NIST GC Methods, and Retention Index Database. 
Click here to learn more>> 
 
 

NIST 11: What’s New and What Value Does it Offer? Part 3

The previous two installments provided information on the NIST/EPA/NIH Mass Spectral Database, past and present, and on the use of the NIST MS Search Program in identifying a compound from its mass spectrum using both the NIST EI Database and the NIST Database of spectra obtained using MS/MS techniques. In Part 3, the use of the searches in the Other Search tab view is examined. These searches can be beneficial to the identity of compounds from mass spectra obtained by ionization techniques other than EI and from data that provides a higher accuracy of the measure m/z value than is usually available for EI data.

 
 

NIST 11: What’s New and What Value Does it Offer? Part 2

In part 2 of this article David Sparkman continues his examination of the NIST 11 Mass Spectral database, the successor to NIST 08, is a fully evaluated collection of electron ionization (EI) Mass Spectra. Here he looks at the search of spectra and structures and what is contained in the results of those searched, and compatibility with the NIST Peptides MS/MS Databases and where to find them...

 


 HPTLC SOLUTIONS LATEST EDITION 
 
HPTLC Today
What is High Performance TLC and how can you benefit from it?
In contrast to column chromatography (e.g., GC, HPLC), planar chromatography utilizes a flat (planar) stationary phase for separation. In thin-layer chromatography (TLC) this stationary phase is supported by a glass plate or a foil (plastic or aluminium). The TLC plate constitutes an open system, which during analysis passes through the individual steps (sample application, chromatogram development, detection, etc.) in an off-line mode. In this process many samples can be analysed in parallel on the same plate. The possibilities for adjusting and combining numerous parameters in order to optimize the separation create a flexibility that is unsurpassed by any other chromatographic technique.
 


© Separation Science 2012 | Privacy Policy | Terms & Conditions