𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Delayed extraction time-of-flight MALDI mass spectrometry of proteins above 25000 Da

✍ Scribed by Bahr, U.; Stahl-Zeng, J.; Gleitsmann, E.; Karas, M.


Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
373 KB
Volume
32
Category
Article
ISSN
1076-5174

No coin nor oath required. For personal study only.

✦ Synopsis


Matrix-assisted laser desorption/ionization (MALDI) with delayed extraction (DE) has been optimized for mass analysis of high-mass proteins and glycoproteins with masses above 25 000 Da. Under optimized experimental conditions, i.e. using a weak extraction Ðeld strength and a long delay time, a steep drop in mass resolution above 30 000 Da is no longer observed and an improvement of more than a factor of 10 is obtained compared with the non-DE case, at least up to 66 kDa in a 1.2 m time-of-Ñight mass analyzer. On this level of resolution the factors limiting further improvements become apparent, i.e. adduct ion formation between matrix and analyte, but also cationization and further non-matrix-related adducts, as well as prompt fragmentation. Moreover, heterogeneity of the sample is often the reason for the detection of broad signals for larger proteins. Within these limitations, DHBs (a 9 : 1 mixture of 2,5-dihydroxybenzoic acid and 2-hydroxy-5-methoxybenzoic acid) gave by far the best results. (


📜 SIMILAR VOLUMES


Mass-correlated Delayed Extraction in Li
✍ S.V. Kovtoun 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 323 KB 👁 2 views

Theoretical analysis and model calculations were directed to find a means of extending the Wiley-McLarens principles of velocity focusing to wide range mass spectra. Both the cases of time-profiled single-field and double-field operation modes were considered. High mass accuracy over about a 10-fold

An Approach to the Design of Mass-correl
✍ S. V. Kovtoun 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 111 KB 👁 2 views

An algorithm is suggested that allows the implementation of first order velocity (energy) focusing in a linear, single field, time-of-flight mass spectrometer (TOF/MS) over a broad mass range using a time-dependent mass-corrected extraction field. The interpolation formula for extraction field depen

Capillary isoelectric focusing–electrosp
✍ Jing Wei; Cheng S. Lee; Iulia M. Lazar; Milton L. Lee 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 88 KB 👁 1 views

On-line capillary isoelectric focusing CIEF ᎐electrospray ionization Ž . time-of-flight mass spectrometry ESI᎐TOFMS as a two-dimensional separation Ž system is employed for high-resolution analysis of model proteins myoglobin and . ␤-lactoglobulin and human hemoglobin variants C, S, F, and A. The fo

Time-delayed extraction matrix-assisted
✍ Katharina Linnemayr; Philipp Vana; Günter Allmaier 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 200 KB 👁 1 views

Matrix selection and sample preparation technique, namely finding a suitable matrix-analyte combination, has been one of the most important concerns in applying positive and negative ion matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to synthetic polymers. Most matrices used i

Quantitative evaluation of protein–prote
✍ Ayeda Ayed; Andrew N. Krutchinsky; Werner Ens; Kenneth G. Standing; Harry W. Duc 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 138 KB 👁 1 views

A mass spectrometer coupling electrospray ionization with time-of-flight mass spectrometry (ESI-TOFMS) has been used to investigate the oligomeric species of Escherichia coli citrate synthase, and to determine the effect of nicotinamide adenine dinucleotide (NADH), an allosteric inhibitor of this en