Methods for microfabricating composite materials and composite materials prepared there from are described herein. The sacrificial material can be etched or patterned to create a two-dimensional and/or three-dimensional sacrificial material structure. The resulting sacrificial material structure can be embedded in one or more embedding materials. The sacrificial material(s) are materials whose solubility can be altered by application of a stimulus typically pH, and/or temperature, light, pH, pressure, presence of absence of ions, and combinations thereof. The embedding materials can contain one or more additives that modify one or more properties of the embedding materials, such as degradation properties, porosity, mechanical properties, viscosity, conductive properties, and combinations thereof. The composite materials can be used in tissue engineering, drug screening, toxin detection, drug delivery, filtrations, bioseparations, and as microfluidic devices for fluid mixing and structural repair.