A device and method are provided for sealing a puncture in a body vessel. The device has an elongated body having a proximal end and a distal end sized to be positioned within a lumen of the body vessel; at least one closure composition precursor lumen within the elongated body having a entrance port adjacent the proximal end of the elongated body through which one or more fluent closure composition precursors can be delivered into the closure composition precursor lumen and an exit port adjacent the distal end of the elongated body through which the one or more fluent closure composition precursors can be delivered outside the vessel adjacent the vessel puncture; and a microwave antenna for delivering microwave energy adjacent the distal end of the elongated body to the fluent closure compound precursor. The microwave antenna according to this embodiment is preferably incorporated onto the elongated body adjacent the body distal end. Alternatively, the device can include a guidewire lumen and a guidewire which includes a microwave antenna.