Effect of different solution flow rates on analyte ion signals in nano-ESI MS, or: when does ESI turn into nano-ESI?

Quantification of Signaling Lipids by Nano-Electrospray Ionization Tandem Mass Spectrometry (Nano-ESI MS/MS)

Lipids, such as phosphoinositides (PIPs) and diacylglycerol (DAG), are important signaling intermediates involved in cellular processes such as T cell receptor (TCR)-mediated signal transduction. Here we report identification and quantification of PIP, PIP2 and DAG from crude lipid extracts. Capitalizing on the different extraction properties of PIPs and DAGs allowed us to efficiently recover b...

Structural Analysis of -Carrageenan Sulfated Oligosaccharides by Positive Mode Nano-ESI- FTICR-MS and MS/MS by SORI-CID

Structural analysis of sulfated oligosaccharides from -carrageenan of up to ten residues (MW 2 kDa) was successfully carried out by positive mode nano-ESI-FTICR-MS together with MS/MS using sustained off-resonance irradiation-collision induced dissociation (SORI-CID). Glycosidic bond cleavage reactions via the Band Y-types of fragmentation were observed and enabled complete sequencing of the ol...

Reduction of Ionization Suppression in Water Samples when Using LC-ESI-MS in Negative Ion Mode

Experimental modifications that inhibited ionization suppression when using LC-ESI-MS (liquid chromatographyelectrospray ionization-mass spectrometry) in negative ion mode are described for two classes of materials: steroid estrogens and acidic herbicides. Introduction Ionization suppression is a problem when using electrospray ionization (ESI) in negative ion mode. It leads to an apparent redu...

ESI and nanoESI - CID - MS / MS

LC-ESI-MS/MS Alkaloidal Profiling and Biological Investigation of Cleistocactus winteri Stems

Cleistocactus winteri is a succulent plant of the Cactaceae family, commonly known as the golden rat tail. Many members of the Cactaceae family are the focus of chemical and biological studies as they contain bioactive compounds, well known for their health-related properties. We aimed to investigate Cleistocactus winteri stems both phytochemically and biologicallyfor the firs...