Glycosylation creates an intricate and complex code for biological information that plays a role in cell-cell communication, infection, and immunity among many biological events. Dynamic changes in the glycosylation status of cells have been observed in tumor cell metastasis and cell differentiation but have been difficult to analyze because of a lack of high-throughput and facile technologies. Here, we present a method for the rapid evaluation of differences in the glycosylation of heterogeneous mammalian samples using a ratiometric two-color lectin microarray approach. This work represents a significant improvement in glycomics technology and sets the stage for the systematic evaluation of how glycans encode biological information in complex systems. [ABSTRACT FROM AUTHOR]