Evaluation of an automated SPE method for samples derived from capillary microsampling
• The automated workflow described gave equivalent results (LLOQ, precision, accuracy) compared to samples processed manually by protein precipitation. The overall time/sample is slightly higher for the automated protocol. However, since only minimal intervention is required, process safety is superior and human resources are freed up for other tasks.
• The automated protocol may be further optimized in several aspects. As shown a volume of 20 μL is sufficient for complete elution of the analyte from the cartridge. Figure 6 indicates that a loading volume of 2-5 μL diluted plasma is sufficient allowing the use of low-volume samples. Both aspects are important for further optimizing this protocol for analysis of samples originating from studies using microsampling techniques.
• Methods for the automated optimization of the SPE conditions exist and will be applied in future studies.
• The automated protocol may be further optimized in several aspects. As shown a volume of 20 μL is sufficient for complete elution of the analyte from the cartridge. Figure 6 indicates that a loading volume of 2-5 μL diluted plasma is sufficient allowing the use of low-volume samples. Both aspects are important for further optimizing this protocol for analysis of samples originating from studies using microsampling techniques.
• Methods for the automated optimization of the SPE conditions exist and will be applied in future studies.