Thirty-five melamine-formaldehyde (MF) monolithic materials with bimodal pore distributions were synthesized in fused silica capillaries by catalyst-free polycondensation, starting with an aqueous MF precondensate, using acetonitrile as macroporogen and a variety of aliphatic polyethers and triblock copolymeric surfactants as porogens and mesoporogens, respectively. By varying the prepolymer composition and the type and molecular weights of the polymeric porogen components, a library of porous monolithic materials were produced, covering a range of meso- and macroporous properties. A multivariate evaluation revealed that the amount of surfactant was the strongest contributor to specific surface area and pore volume, and to the inversely related mesopore size, whereas the macropore dimension was mainly controlled by the amount of aliphatic polyether porogen. One of these capillary monoliths, chosen based on the combination of meso- and macropores providing optimal percolative flow and accessible surface area, was synthesiz¬ed in the presence of N-Fmoc and O-Et protected phosphoserine and phosphotyrosine, in order to prepare molecularly imprinted monoliths with surface layers selective for phosphopeptides. These imprinted monoliths were characterized alongside non-imprinted monoliths by a variety of techniques and finally evaluated by liquid chromatography-mass spectrometry in the capillary format to assess their abilities to trap and release phosphorylated amino acids and peptides from partly aqueous media. Selective enrichment of phosphorylated targets was demonstrated, suggesting that these materials could be useful as trapping media in affinity-based phosphoproteomics.