A modular and reconfigurable multi-stage microreactor cartridge apparatus provides a manifold for removably attaching multiple microfluidic components such as microreactors. The microfluidic components are attached at microfluidic component ports having two input/output terminals, which microfluidic component ports are connected via connections internal to the manifold to other microfluidic component ports providing a microfluidic circuit. The microfluidic component may be a microfluidic circuit plug-in or a cartridge having a mounting block with two input/output terminals and a fastener aperture and fluidic tubing having a first and second transport portion and a body portion, the three portions being disposed in substantially parallel planes and the body portion being would in a coil around a spool. The coil is connected to the mounting block by either epoxy protector or L-bracket. The cartridge has a first and a second remote input/output terminal connected to the first and second transport lines respectively.