The invention provides arrays of molecules where the molecules (e.g., glycans) are attached to the arrays by cleavable linkers. The invention also provides methods for using these arrays, methods for identifying the structural elements of molecules bound to these arrays by using the cleavable linkers, especially the structural elements that are important for binding to test samples. The invention further provides methods for evaluating whether test samples and test molecules can bind to distinct glycans on the arrays and useful glycans identified using the methods and arrays provided herein.