The present invention relates generally to compositions and methods comprising abiotic, synthetic polymers with affinity and specificity to proteins. The synthetic polymers are an improvement over biological agents by providing a simpler, less expensive, and customizable platform for binding to proteins. In one embodiment, the compositions and methods relate to synthetic polymers with affinity and specificity to vascular endothelial growth factor (VEGF). In one embodiment, the compositions are useful for treating diseases and disorders related to the overexpression of VEGF. In one embodiment, the compositions are useful for treating cancer. In one embodiment, the compositions are useful for detecting VEGF levels from biological samples. In one embodiment, the compositions are useful for detecting overexpression of VEGF from biological samples. In one embodiment, the compositions are used to diagnose cancer.