Apparatus

Abstract

A reactor for forming fully coated particles having a solid core, the reactor comprises a reactor vessel which is configured to receive particles, and a gas phase coating mechanism that is configured to selectively introduce pulses of gas phase materials that form a coating on the particles. The reactor also includes a sieve (16) that is located within the reactor vessel, and a forcing means that is configured to force the particles through the sieve (16) in use. The sieve is configured to deagglomerate any particle aggregates formed in the reactor vessel upon forcing of the particles by the forcing means through the sieve.

1 . A reactor for forming a plurality of fully coated particles having solid cores, the reactor comprising:
 a reactor vessel configured to receive particles in the form of microparticles comprising a biologically active agent;   a gas phase coating mechanism configured to selectively introduce pulses of gas phase materials that form a coating on the particles;   at least one sieve located within the reactor vessel; and   a forcing means configured to force the particles through the sieve in use,   wherein the sieve is configured to deagglomerate any particle aggregates formed in the reactor vessel upon forcing of the particles by the forcing means through the sieve.   
     
     
         2 . The reactor according to  claim 1 , wherein the forcing means comprises shaking, tapping, oscillating, tumbling, horizontal rotation, periodic displacement of the sieve, centrifugal force, sonic vibration, ultrasonic vibration, vacuum, air column, pressure gradient, gas flow, brushing, gravitational or a combination thereof. 
     
     
         3 . The reactor according to  claim 1 , wherein the forcing means is integrated with the reactor vessel and is or includes ultrasonic vibration such that the vessel and sieve act as a sonic sifter. 
     
     
         4 . The reactor according to  claim 1 , wherein the forcing means comprises a forcing aid to aid in forcing the particles through the sieve in use. 
     
     
         5 . The reactor according to  claim 1 , wherein the ratio of the size of particles to the sieve mesh size is about 1:2. 
     
     
         6 . The reactor according to  claim 1 , further comprising a plurality of sieves located within the reactor vessel, each sieve having progressively finer meshes in the direction of forceable movement of the particles. 
     
     
         7 . The reactor according to  claim 1 , wherein the reactor vessel comprises more than one reactor chamber, the sieve being located between each neighbouring reactor chamber, the gas phase coating mechanism being configured to selectively introduce one or more pulses of gas phase material to the particles in one or each reactor chamber. 
     
     
         8 . The reactor according to  claim 7 , further comprising a particle position changing means configured to action movement of the particles from one physical space in the reactor to another to permit subsequent forcing of the particles through the sieve. 
     
     
         9 . The reactor according to  claim 8 , wherein the particle position changing means is a movement member configured to physically move each of the reactor chambers so as to switch places of the reactor chambers. 
     
     
         10 . The reactor according to  claim 9 , wherein the movement member is configured to rotate the reactor chambers along a single axis to switch places of the reactor chambers. 
     
     
         11 . The reactor according to  claim 9 , wherein the movement member is configured to switch places of the reactor chambers without rotation of the reactor chambers. 
     
     
         12 . The reactor according to  claim 9 , wherein each reactor chamber includes a sieve located on an intermediate surface, the intermediate surface being located between neighbouring reactor chambers upon switching of their places so that a sieve is located between the reactor chambers at any given time. 
     
     
         13 . The reactor according to  claim 8  wherein the particle position changing means is a particle transport mechanism configured to transport the particles between each of the reactor chambers. 
     
     
         14 . The reactor according to  claim 8 , wherein the particle position changing means includes a movement member configured to physically move each of the reactor chambers so as to switch places of the reactor chambers and a particle transport mechanism configured to transport the particles between each of the reactor chambers. 
     
     
         15 . The reactor according to  claim 7 , further comprising a stop means positioned relative to each sieve to selectively prevent passing of the particles through the sieve into a neighbouring reactor chamber. 
     
     
         16 .- 17 . (canceled) 
     
     
         18 . The reactor according to  claim 1 , wherein the gas phase coating mechanism incorporates one of the following gas phase coating techniques: atomic layer deposition (ALD), atomic layer epitaxy (ALE), molecular layer deposition (MLD), molecular layer epitaxy (MLE), chemical vapor deposition (CVD), atomic layer CVD, molecular layer CVD, physical vapor deposition (PVD), sputtering PVD, reactive sputtering PVD, evaporation PVD, binary reaction sequence chemistry. 
     
     
         19 . A method of forming fully coated particles comprising the steps of:
 i) providing a plurality of particles in the form of microparticles comprising a biologically active agent into a gas phase coating reactor;   ii) subjecting those particles to pulses of gas phase materials by a gas phase coating technique so as to coat the particles;   iii) forcing the coated particles through a sieve within the reactor to deagglomerate any particle aggregates formed during step ii); and   iv) repeating steps ii) and iii) to form particles with a solid core, the solid core being fully enclosed by the coating formed by the gas phase coating technique.   
     
     
         20 . The method according to  claim 19 , wherein step ii) includes subjecting the particles to pulses of gas phase materials by a gas phase coating technique so as to perform at least one ALD cycle and step iii) includes forcing the particles through the sieve after the at least one ALD cycle performed in step ii). 
     
     
         21 . The reactor according to  claim 1 , wherein the gas phase coating mechanism is configured to introduce pulses of gas phase materials to perform at least one ALD cycle between the forcing means forcing the particles through the sieve.