Madli tof ms microflex lt

Example 10

Methods. Five hundred fifty six (556) serum samples that had been previously analyzed by routine clinical PEL/IFE testing were evaluated by MADLI-TOF MS (Microflex LT, Bruker Daltonics). Prior to analysis, intact immunoglobulins were isolated from serum with Capture Select™ (Hu)LC-kappa and LC-lambda affinity resin (Life Technologies) and reduced with tris(2-carboxyethyl)phosphine hydrochloride (TCEP-HCl, Thermo Scientific). Purified samples were prepared for MALDI-TOF analysis using dried droplet method and α-cyano-4-hydroxycinnamic acid as matrix. Mass analysis was performed in positive ion mode with summation of 500 laser shots.

Results. For spectral analysis, the ion distribution of the MH+1 and MH+2 charge states of the light chain were compared to the spectrum of normal serum. Any monoclonal abnormalities were distinguished from the normal pattern. Of the 556 samples assayed, abnormal patterns were identified in 406 of 421 samples (96%) that were positive by IFE. Abnormalities were also noted in 23 of 126 samples (18%) that were negative by IFE. Of the 9 samples that were indeterminate by IFE, abnormalities were noted in 2.

Example 10

Methods. Five hundred fifty six (556) serum samples that had been previously analyzed by routine clinical PEL/IFE testing were evaluated by MADLI-TOF MS (Microflex LT, Bruker Daltonics). Prior to analysis, intact immunoglobulins were isolated from serum with Capture Select™ (Hu)LC-kappa and LC-lambda affinity resin (Life Technologies) and reduced with tris(2-carboxyethyl)phosphine hydrochloride (TCEP-HCl, Thermo Scientific). Purified samples were prepared for MALDI-TOF analysis using dried droplet method and α-cyano-4-hydroxycinnamic acid as matrix. Mass analysis was performed in positive ion mode with summation of 500 laser shots.

Results. For spectral analysis, the ion distribution of the MH+1 and MH+2 charge states of the light chain were compared to the spectrum of normal serum. Any monoclonal abnormalities were distinguished from the normal pattern. Of the 556 samples assayed, abnormal patterns were identified in 406 of 421 samples (96%) that were positive by IFE. Abnormalities were also noted in 23 of 126 samples (18%) that were negative by IFE. Of the 9 samples that were indeterminate by IFE, abnormalities were noted in 2.