Method and apparatus for microneedle transdermal delivery
A method for forming microspheres containing bioactive material, comprising dissolving a polymer matrix, such as albumin or beta-cyclodextrin, in an aqueous medium in a first vessel; contacting the dissolved polymer matrix with a crosslinking agent, such as glutaraldehyde, to crosslink the polymer matrix and the crosslinking agent; neutralizing with sodium bisulfate any excess crosslinking agent remaining after crosslinking is substantially complete; solubilizing in a second vessel a bioactive material in an aqueous solution; mixing the solubilized bioactive material together with the neutralized crosslinked polymer matrix in solution to form a mixture; and, spray drying the mixture to produce nanospheres, whereby substantial bioactivity of the biomaterial is retained upon cellular uptake.
1. A method for incorporating a vaccine into an orally dissolving film, comprising:
(a) preparing a polymeric solution comprising a nonorganic solvent and at least two polymers selected from the group consisting of hydroxyl-propyl methylcellulose acetate succinate, cellulose acetate phthalate polymer (CAP), ethyl cellulose, HPMC-AS, a mixture of copolymers derived from esters of acrylic and methacrylic acids, and chitosan glycol;
(b) preparing nanoparticles or microparticles of encapsulated vaccine by spray drying at a temperature higher than the boiling point of the nonorganic solvent and lower than a temperature at which the vaccine degrades a mixture of a proteinaceous vaccine material and the polymeric solution; and,
(c) casting the nanoparticles or microparticles in a film solution to form the film.
2. The method of claim 1 , wherein the film solution comprises a film forming polymer.
3. The method of claim 2 , wherein the film forming polymer comprises pea starch.
4. The method of claim 3 , wherein the film solution comprises a plasticizer.
5. The method of claim 4 , wherein the nanoparticles or microparticles comprise an adjuvant.
6. The method of claim 1 , wherein the nanoparticle or microparticle has an average particle size in a range of 1,000 nm to about 5,500 nm.