Enabling a Microfluidic RFID Readout System via Miniaturization and Integration We present a microfluidic read-out platform concept for miniaturized radio-frequency identification (RFID) tags that will help identifying natural underground sources. Designed microfluidic platform has embedded spiral reader antennas for data communication via near field magnetic coupling. To enable near field magnetic coupling with the reader antennas at reasonably low frequencies, we developed electrically ultrasmall (380 μm × 380 μm × 15 μm with resonance ~0.75 GHz) on-chip antennas. Concept feasibility was proven by a set of experiments. First, data communication between an RFIDreader and a printed circuit board-level passive tag was demonstrated through miniaturized antennas. Second, coupling between passive reader and on-chip antennas was shown inside the fluidic environment. In addition, a chip separation mechanism was introduced to the platform to prevent cross-coupling events between RFID tags.