In this study, a multiple ramped CP (RAMPnCP) method is proposed. A maximum polarization transfer is achieved on the glycine using RAMPnCP. A theoretical solution is also derived based on the reciprocity relation indicating CP is bidirectional. The experimental results match well with the theoretical model. Under the T-1 rho compensation, all the polarizations of the (CH)-C-13, (CH2)-C-13, (CH3)-C-13, and (COOH)-C-13 groups become similar, which can be used in the quantitative measurement of the C-13 spectrum. It is quite promising to become a best member in quantitative study in the future. (C) 2017 Elsevier B.V. All rights reserved.