Abstract: Peptides can be derivatised such that, when ionised and analysed by mass spectrometry, those containing arginine residues give characteristic peak patterns. Peaks corresponding to arginine-containing peptides can therefore be selected from a mass spectrum in order to simplify and improve peptide analysis. Suitable labels give derivatised peptides that have the ability to form both a stabilised ion species ([P]+) and a protonated ion molecular species ([P+H]+) that differ by one average mass unit. A characteristic peak pattern is seen.

Abstract: Methods of analysing peptides by mass spectrometry are disclosed. In particular, methods of analysing peptides by fragmentation mass spectrometry (MSn, where n is at least 2) are disclosed. The methods involve derivatisation of a peptide at its N-terminus such that peaks corresponding to both a and b (and y) daughter ions are identifiable in fragmentation mass spectra of the derivatised peptide. The fragmentation mass spectra of the derivatised peptide contain additional information (relative to the fragmentation mass spectra of the underivatised peptide) useful for determination of the amino acid sequence of the peptide.

Abstract: Methods and systems are provided for producing transaction cards. A reference number is assigned to each of the cards, which are fabricated in accordance with a specification. Usually the specification is provided externally from a card issuer that wishes to have the cards fabricated for distribution. After fabrication, the reference number assigned to each of the cards is compared with a database to identify any duplication. The identity of a responsible operator may be recorded during one or more stages during fabrication and/or as part of the process of comparing with previously assigned numbers.

Abstract: Methods and systems are provided for producing transaction cards. A reference number is assigned to each of the cards, which are fabricated in accordance with a specification. Usually the specification is provided externally from a card issuer that wishes to have the cards fabricated for distribution. After fabrication, the reference number assigned to each of the cards is compared with a database to identify any duplication. The identity of a responsible operator may be recorded during one or more stages during fabrication and/or as part of the process of comparing with previously assigned numbers.