Methods are provided for surface modifying a hydrophobic polymer substrate to increase wettability comprising the steps of pre-treating the hydrophobic polymer substrate with a radio frequency (RF)-generated first plasma and a RF-generated second plasma wherein the first plasma and the second plasma are applied sequentially, coating the hydrophobic polymer substrate with a hydrophilic coating; and polymerizing the hydrophilic coating on the hydrophobic polymer substrate by exposure to a RF-generated third plasma.