Varian, Inc.

Agilent Technologies, Inc.

August Specht

Kenneth R Newton

Gregory J Wells

Bert David Egley

Dave Deford

An ion processing apparatus includes a plurality of electrodes, first and second insulators, a housing, and a plurality of compliant first supports and second supports. Each electrode has a length along a central axis, and includes a first end region and an axially opposing second end region. The first and second insulators are coaxially disposed about the first and second end regions, respectively. The housing is coaxially disposed about the electrodes, the first insulator and the second insulator. The first supports extend between, and into contact with, the first insulator and the housing. The second supports extend between, and into contact with, the second insulator and the housing. The supports isolate the electrodes from external forces.

Linear ion processing apparatus with improved mechanical isolation and assembly

In some embodiments, a method of optimizing operating parameters of an analytical instrument (e.g. lens voltages of a mass spectrometer) includes steps taken to minimize the method duration in the presence of substantial instrument noise and/or drift. Some methods include selecting a best point between a default instrument parameter set (vector) and a most-recent optimum parameter set; building a starting simplex at the selected best point location in parameter-space; and advancing the simplex to find an optimal parameter vector. The best simplex points are periodically re-measured, and the resulting readings are used to replace and/or average previous readings. The algorithm convergence speed may be adjusted by reducing simplex contractions gradually. The method may operate using all-integer parameter values, recognize parameter values that are out of an instrument range, and operate under the control of the instrument itself rather than an associated control computer.

Simplex optimization methods for instrumentation tuning

In some embodiments, a tandem (MS/MS) mass spectrometry method includes selecting a collision-induced dissociation (CID) voltage amplitude and a q-parameter value for a quadrupole ion trap to optimize a daughter ion fragmentation process for a given parent ion mass-to-charge (m/z) ratio. The q and CID voltage values may be selected according to a look-up table and/or using approximate analytical expressions. The correspondence between m/z values and (q, CID) value pairs may be established by pre-measurement calibration. A fragmentation-optimized q value may be computed according to m/z, and a CID voltage value may be determined according to the computed q value. A user may also force q to another value, for example in order to facilitate trapping of a desired daughter ion mass range, and the controller computes a CID voltage value according to the forced q value.

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Walnut Creek, CA, United States of America

August Specht