摘要 |
The present invention relates to a method and apparatus for producing uniform polymeric spheres with controllable permeability. This invention may be useful for encapsulating living cells or tissue or chemicals or medicines in uniform polymeric spheres. In particular, this invention relates to polymeric microspheres made from polycation and polyanion polymer solutions. An apparatus includes airtight housing 1 having top 3 and bottom 25 chambers. Top chamber 3 includes pressure regulator means 5, stationary polyanion reservoir tank 7, polycation reservoir tank 27, and feed line 9 to adjustable tank 11. Tank 11 is associated with oscillator 13, nozzle 14 and capacitance means 19. Nozzle 14 and oscillator 3 cooperate to form polyanion droplets. In the bottom chamber 25 annular nozzle 50 is used to form an annular jet of polycation solution. The droplets and polycation jet are mixed at minimal impact velocities to form uniform polymeric sphere.
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