Application of Microfluidic Devices for Biomarker Detection

Microfluidic devices that will enable global proteomic profiling will be particularly useful for biomarker discovery applications where the researcher is interested in comprehensively mapping all peptide/protein components in given biological fluids or tissues. Differential protein expression analysis will enable the discovery of specific protein markers or protein co-expression patterns that 

An essential finding that emerged from proteomic experiments was that the number of identified proteins was strongly dependent on the amount of sample consumed for analysis. The LC chip enabled the injection of 1 pL of sample and resulted in the identification of 77 proteins, of which 39 proteins had p 0.001. A conventional LC system that used conditions similar to the chip (2 cm separation column, 1 pL sample injection) provided comparable 

Even though the microfluidic-MS analysis was performed with low injection volumes, it enabled the identification of five putative biomarkers 39,40 proliferating cell nuclear antigen (PCNA), cathepsin D and keratins K8, K18 and K19 (Table 7.1). All corresponding peptides that identified these proteins had p 0.001, confirming the reliability of the match. PCNA is a protein involved 

Microfluidic Bioanalytical Platforms with Mass Spectrometry Table 7.1 List of putative cancer biomarkers identified with the microfluidic 

protonated molecular ion z, peptide charge state p, probability of a random match MW, protein molecular weight Sp, peptide preliminary score 

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