This dissertation presents characteristics and utilities of enhanced microsensors for chemical land oncological applications. Simple and cheap techniques for fabrication of mechanical and electrical sensing devices in micro scale have been developed. Critically buckled resonant microbrides with active sensing polymer layer detect chemical gases as it swells volumetrically and its resonant frequency shifts due to altered tension in the microbridges. Substantial improvements in quality factor and frequency stability of the microresonators under ambient pressure and temperature condition have been demonstrated. For potential applications in monitoring electrical behavior of human colorectal carcinoma cells, bio-functionalized electrical graphene microsensors on a sapphire substrate have been developed. The biosensors have shown substantial increase in impedance compared to its baseline with a small number of captured cells. In addition to the development of microsensors, experimental procedure for visualization of metastatic colorectal tumor cells in mice using multiphoton fluorescent microscopy is presented.