Integrated barcode chips for rapid, multiplexed analysis of proteins in microliter quantities of blood

As the tissue that contains the largest representation of the human proteome(1), blood is the most important fluid for clinical diagnostics(2-4). However, although changes of plasma protein profiles reflect physiological or pathological conditions associated with many human diseases, only a handful of plasma proteins are routinely used in clinical tests. Reasons for this include the intrinsic complexity of the plasma proteome(1), the heterogeneity of human diseases and the rapid degradation of proteins in sampled blood(5). We report an integrated microfluidic system, the integrated blood barcode chip that can sensitively sample a large panel of protein biomarkers over broad concentration ranges and within 10 min of sample collection. It enables on-chip blood separation and rapid measurement of a panel of plasma proteins from quantities of whole blood as small as those obtained by a finger prick. Our device holds potential for inexpensive, noninvasive and informative clinical diagnoses, particularly in point-of-care settings.