A new sample ionization technique, atmospheric pressure matrix-assisted laser desorption/ionization (AP MALDI), was coupled with a commercial ion trap mass spectrometer. This configuration enables the application-specific selection of external atmospheric ionization sources: the electrospray/APCI (commercially available) and AP MALDI (built in-house), which can be readily interchanged within mi...

background: culture media enrichment through the addition of protein hydrolysates is beneficial for achieving higher protein expression. methods: in this study, designing the optimum mixture of four soy and casein-derived hydrolysates was successfully performed by design of experiment and specific productivity increased in all predicted combinations. protein profile of recombinant cho (rcho) ce...

Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has revolutionized the identification of clinical bacterial and yeast isolates. However, data describing the reproducibility of MALDI-TOF MS for microbial identification are scarce. In this study, we show that MALDI-TOF MS-based microbial identification is highly reproducible and can tolerate numerous ...

In both atmospheric pressure matrix-assisted laser desorption/ionization (AP MALDI) and vacuum MALDI, the laser typically illuminates the analyte on the front side of an opaque surface (reflection geometry). Another configuration consisting of laser illumination through the sample backside (transmission geometry) has been used in conventional MALDI; however, its use and the number of reports in...

• Here we present an N-terminal derivatization approach, using TMPP-Ac-Osu that improves the HPLC performance for small hydrophilic phosphopeptides. • This approach is compatible with LC/MS and LC/MALDI. • The chromatographic enhancement was evaluated by on-line nanoscale HPLC coupled with Electrospray on a Q-Tof PremierTM. • LC-MALDI/MS/MS analysis was also investigated. Both MS/MS on a Q-Tof ...

MALDI-TOF-MS is a soft ionization technique that has the potential to determine the molecular weight for various compounds, particularly for large biomolecules.1-3 Recently, considerable interest has been focused on the analysis of synthetic polymers by MALDI-MS.4 Compared with the traditional methods of polymer analysis, MALDI-MS can provide more abundant information on molecular weight, repea...

The identification of proteins involved in tumour progression or which permit enhanced or novel therapeutic targeting is essential for cancer research. Direct MALDI analysis of tissue sections is rapidly demonstrating its potential for protein imaging and profiling in the investigation of a range of disease states including cancer. MALDI-mass spectrometry imaging (MALDI-MSI) has been used here ...

MALDI MSI has been recently applied as an innovative tool for detection of molecular distribution within a specific tissue. MALDI MSI requires deposition of an organic compound, known as matrix, on the tissue of interest to assist analyte desorption and ionization, in which the matrix crystal homogeneity and size greatly influence the imaging reproducibility and spatial resolution in MALDI MSI....

Quantitative analysis with mass spectrometry (MS) is important but challenging. Matrix-assisted laser desorption/ionization (MALDI) coupled with time-of-flight (TOF) MS offers superior sensitivity, resolution and speed, but such techniques have numerous disadvantages that hinder quantitative analyses. This review summarizes essential obstacles to analyte quantification with MALDI-TOF MS, includ...

In this study, the previously reported integrated selective enrichment target (ISET)-MALDI-MS analysis was implemented with ssDNA aptamer to address the specific capturing of thrombin in complex samples. By applying a thrombin specific aptamer linked to ISET-MALDI-MS detection, a proof of concept of antibody fragment background reduction in the ISET-MALDI-MS readout is presented. Detection sens...