METHODS AND COMPOSITIONS FOR REFINING FEATURE BOUNDARIES IN MOLECULAR ARRAYS

Provided in some aspects are methods for light-controlled in situ surface patterning of a substrate. Compositions such as nucleic acid arrays produced by the methods are also disclosed. Further provided in some aspects are methods for light-controlled in situ refinement of nucleic acid array feature boundaries. In some embodiments, a method disclosed herein comprises using photoresist for photocontrollable removal, blocking, and/or inactivation of nucleic acid molecules at feature boundaries. A large diversity of barcodes can be created in molecules on the substrate via sequential rounds of light exposure, hybridization, ligation, and further interceded and/or followed by one or more rounds of photocontrollable refinement of array feature boundaries, to improve spatial array resolution and sensitivity.