Page 16 - Clinical-Medical Solution for Clinical Chemistry

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

120
n = 6
100
Absorbance ratio [%] 60
80

40

20

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 4. Absorption ratio with each lysis protocols. Freeze/thaw with -80ºC was effective lysis procedure.
-20ºC was also ef cient at the volume of 0.2 mL. However, the pipetting technique in uenced
the number of hemoglobin in such a small volume. Ammonium chloride was also effective method.
The reason why is that it was diluted 3 times.

Incorporation of ISP into erythrocytes by LC/MS/MS

ISP are spiked to the whole blood and separated only Compared with these results, about 90% of tacrolimus,
spiked and centrifuged sample and reference sample sirolimus, everolimus and about 60% of CSA were
which includes particulates. Where the ISP are located located to the erythrocytes.
was tested by LC/MS/MS (LCMS-8060) for the two After the experiment, ISP recovery rate with each lysis
samples (plasma and whole blood). Fig.5 shows the MRM protocols were evaluated by LC/MS/MS. The whole blood
chromatogram of the ISP and internal standard. sample were performed for reference.

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