A micro-scale artificial gland is disclosed in the form of an independent unit for promoting biological activity. The artificial gland includes cells formed in a membrane enclosing a reservoir. The reservoir is a bio-reactor capable of containing a product of activity of the cells. The reservoir comprises a gas, a liquid, and a gel and preferably also contains nanoparticles, a buffer, a surfactant, and, a gel precursor. The reservoir may also contain cells. Nanoparticles may also surround the artificial gland to form a protective coating. A variety of methods are disclosed for making the artificial gland by directed assembly of cells into the artificial micro-gland by gel, liquid or bubble templating. All involve coating the surface of gel, droplet or bubble with the living cells and the stabilizing the cells on the surface of gels, droplets or bubbles.
