Abstract: The present invention relates to methods and compositions for the normalization of complex analyte mixtures. The invention allows the preparation of profiled samples from highly complex analyte mixtures, allowing the identification of relevant targets or biomarkers. The invention also relates to methods for producing devices, such as a support, suitable for normalization of complex analyte samples. The invention can be used for the normalization of any complex mixture, such as immunogenic libraries, particularly of human source, and to identify or produce biomarkers highly relevant to human traits or conditions.