This review paper first discusses the design considerations that are being applied in the development of a highly sensitive, miniaturised and high throughput assay microcalorimeter. Major factors include reaction chamber, thermal insulation, fluid handling, mixing techniques and temperature sensing. Miniaturisation is the key to handle smaller sample volume within the nanoliter to picoliter regions, which is made possible by advancement in materials and fabrication technologies. Materials under review include silicon, silicon nitride, parylene-C, PMMA, PDMS, SU-8 and polyimide. The materials are compared in terms of size, cost, biocompatibility, chemical resistance and thermal properties. Finally, we compile the list of works across the globe and their contributions that demonstrated microcalorimeter prototypes with high thermal insulation, precise microfluidic handling capabilities, rapid mixing of fluids and high throughputs. This review offers broad perspectives and insights for those working on microcalorimeter, enthalpy arrays, microfluidic biosensor, thermal sensor and micromixer.