ECD mass spectrum

Typically, the dominant product in an ECD mass spectrum corresponds to the charge-reduced radical cation [M + nH]<"- >+, that is, the precursor ion that has captured an electron but has not fragmented into sequence-specific ions. Another common product is [M + +, that is, the precursor ion that has captured an electron and... 

An alternative approach is plasma ECD [86], in which electrons (0.1-15 eV) are collided with pulsed nitrogen gas prior to the trapping of ions in the ICR cell. The induced plasma conditions result in significant increase in ECD efficiency. A single plasma ECD mass spectrum of carbonic anhydrase ca 29 kDa) showed peaks corresponding to cleavage of 183/253 N-Ca bonds c/116/258 by activated ion ECD. 

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