Page 18 - Clinical-Medical Solution for Clinical Chemistry

Evaluation of Blood Lysis Procedures prior to Automated
Sample Preparation for Immunosuppressant Assay by LC-MS/MS

ISP recovery rate with each lysis protocols

Area ratio of ISP which was devided by peak area of reproducibility was very low. This is because freezing time
reference was shown in Fig. 6. There are a correlation was not suf cient. F/T with -80ºC was the most ef cient
between the results of UV spectrophotometer and LC/MS. pre-treatment method for CLAM-2000. Ammonium
Freeze/thaw with -80ºC was the closest to the reference chloride was an alternative method. However, it requires
sample. -20ºC was also effective. However, the sample preparation.

150
Tacrolimus n = 6
Sirolimus
120 Everolimus
Recovery rate [%] 90
CSA

60

30

0
Reference HCl Ultrasound_5min Ultrasound_10min Ultrasound_20min F/T_0.2mL_-20ºC F/T_0.2mL_-80ºC F/T_1mL_-20ºC F/T_1mL_-80ºC
Ammonium Chloride

Figure 6. Area ratio of tacrolimus, sirolimus, everolimus, and CSA.
There are a correlation between lysis ef ciency and recovery rates of ISP.
(Freeze/thaw with -80ºC was the closest to the reference sample)

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