In situ determination of acceptable resuspension in pharmaceutical products using water proton NMR
A method of using the transverse relaxation rate (R 2 ) of solvent NMR signal to noninvasively assess if an alum-containing product, such as a vaccine, has been acceptably resuspended for use following transport and/or storage. This technique allows for the manufacturer and/or distributor and/or end user to monitor for unexpected stressors associated with transport and/or storage including, but not limited to, temperature fluctuations, pH changes, vigorous shaking during transportation, exposure to sunlight, and freezing.
1. A method of determining if particles in an alum-containing product were acceptably resuspended following transport and/or storage, said method comprising:
measuring a transverse relaxation rate of solvent R 2,m in the alum-containing product following transport and/or storage; and
determining if the alum-containing product was properly resuspended by comparing the measured R 2,m to a reference transverse relaxation rate of solvent R 2,r , wherein the reference R 2,r represents an acceptable range of evenly distributed aluminum particles or suspended aluminum particles in the alum-containing product,
wherein when the measured R 2,m is inside the reference R 2,r range, the alum-containing product was acceptably resuspended, and wherein the alum-containing product is contained in a vial, and wherein no additives or probes are added to the vial prior to measurement of the transverse relaxation rate of solvent R 2,m .
2. The method of claim 1 , wherein R 2,m is measured using nuclear magnetic resonance (NMR).
3. The method of claim 1 , wherein R 2,m is measured without opening the vial or withdrawing the contents of the vial containing the alum-containing product.
4. The method of claim 1 , wherein the solvent is water.
5. The method of claim 1 , wherein the alum-containing product comprises single particles in a range from 1 nanometer and 50 microns in diameter.
6. The method of claim 1 , wherein the alum-containing product comprises aluminum-containing salts selected from the group consisting of aluminum hydroxide, aluminum phosphate, alum (KAI(SO 4 )·12H 2 O), aluminum hydroxyphosphate sulfate, and any combination thereof.
7. The method of claim 1 , wherein the alum-containing product is a vaccine comprising alum adjuvants or a pharmaceutical product comprising aluminum particles.
8. The method of claim 1 , wherein acceptable resuspension indicates that the alum-containing product is useable or distributable as intended.
9. The method of claim 1 , wherein the particles are free aluminum particles, aluminum-antigen complexes, or a mixture of free aluminum particles and aluminum-antigen complexes.
10. The method of claim 1 , wherein R 2,m and R 2,r are measured at a substantially similar temperature.
11. A method of determining if particles in an alum-containing product were acceptably resuspended following transport and/or storage, said method comprising:
measuring a transverse relaxation time of solvent T 2,m in the alum-containing product following transport and/or storage; and
determining if the alum-containing product was properly resuspended by comparing the measured T 2,m to a reference transverse relaxation time of solvent T 2,r , wherein the reference T 2,r represents an acceptable range of evenly distributed aluminum particles or suspended aluminum particles in the alum-containing product,
wherein when the measured T 2,m is inside the reference T 2,r range, the alum-containing product was acceptably resuspended, and wherein the alum-containing product is contained in a vial, and wherein no additives or probes are added to the vial prior to measurement of the transverse relaxation time of solvent T 2,m .
12. The method of claim 11 , wherein T 2,m is measured using nuclear magnetic resonance (NMR).
13. The method of claim 11 , wherein T 2,m and T 2,r are measured at a substantially similar temperature.
14. The method of claim 13 , wherein T 2,m is measured without opening the vial or withdrawing the contents of the vial containing the alum-containing product.
15. The method of claim 11 , wherein the solvent is water.
16. The method of claim 11 , wherein the alum-containing product comprises aluminum-containing salts selected from the group consisting of aluminum hydroxide, aluminum phosphate, alum (KAI(SO 4 )·12H 2 O), aluminum hydroxyphosphate sulfate, and any combination thereof.
17. The method of claim 11 , wherein the alum-containing product is a vaccine comprising alum adjuvants or a pharmaceutical product comprising aluminum particles.
18. The method of claim 11 , wherein acceptable resuspension indicates that the alum-containing product is useable or distributable as intended.
19. The method of claim 11 , wherein the alum-containing product comprises single particles in a range from 1 nanometer and 50 microns in diameter.
20. The method of claim 11 , wherein the particles are free aluminum particles, aluminum-antigen complexes, or a mixture of free aluminum particles and aluminum-antigen complexes.