Instrumentation MALDI-ToF

Unlike many mass spectrometers, which allow the use of several different ionization methods on the same instrument, MALDI-TOF instruments are generally single purpose, being devoted exclusively to MALDI. In practice, El and ESI methods are also used with TOP mass spectrometers. However, the continuous nature of these sources causes a natural mismatch to TOF-MS, which is a pulsed technique. The traditional way to couple a continuous ion source to a TOF-MS is to dynamically deflect the ion beam past a narrow slit, thus generating a pulsed ion beam at the exit side of the siit. However, this results in low sensitivity as more than 99% of the ion beam is discarded. 

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