Dry heat diffusion cell and diffusion sampling system

Patent metadata

Field	Value
Publication number	US-10753841-B2
Application number	US-201816102480-A
Country	US
Kind code	B2
Filing date	Aug 13, 2018
Priority date	May 18, 2018
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

A diffusion system to improve the efficiency, accuracy, and consistency of testing the release rate of an active ingredient in semisolid form through a membrane in between a dosage lid and a cell cap mounted on a cell in which a mixer is placed to mix the receptor medium in the cell as the semisolid diffuses through the membrane. The cell can be placed in a heating system to heat the samples. The cell has a sampling arm through which samples of the receptor medium can be extracted without opening the cell cap and dosage lid. The mixer may be cylindrical and may occupy a large surface area of the cell. The mixer may have grooves and other irregularities to increase turbulence while mixing. The system can be automated using an automated sampling and collection station.

First claim

The invention claimed is:

1. A diffusion system, comprising:
a. a cell for receiving a receptor medium;
b. a mixer configured to fit inside the cell to mix the receptor medium in the cell;
c. a cell cap to cover the cell; and
d. a dosage lid to place on top of the cell cap, wherein the cell comprises a main body having an open top, and a sampling arm branching from the main body, the sampling arm having an opening.

2. The diffusion system of claim 1 , wherein the cell cap is configured to fit on top of the cell at the open top, the cell cap comprising a top surface and a floor recessed from the top surface, the floor having an inner wall defining an output orifice having a diameter.

3. The diffusion system of claim 2 , wherein the dosage lid is configured to fit on top of the cell cap, the dosage lid comprising an inner wall defining a lid orifice having a diameter, wherein the diameter of the output orifice is equal to the diameter of the lid orifice, such that when the dosage lid is placed on top of the cell cap, the inner wall of the floor of the cell cap and the inner wall of the dosage lid are aligned.

4. The diffusion system of claim 3 , further comprising a membrane configured to fit in between the cell cap and the dosage lid.

5. A diffusion system, comprising:
a. a cell for receiving a receptor medium;
b. a mixer configured to fit inside the cell to mix the receptor medium in the cell;
c. a cell cap to cover the cell; and
d. a dosage lid to place on top of the cell cap, wherein the cell and the mixer are cylindrical, each defining a longitudinal axis, the cell having an inner diameter and the mixer having a diameter, wherein the inner diameter of the cell is substantially the same as the diameter of the mixer, while allowing the mixer to be spin inside the cell.

6. The diffusion system of claim 5 , wherein mixer has longitudinal groove.

7. The diffusion system of claim 6 , wherein the longitudinal groove is angled relative to the longitudinal axis of the mixer.

8. The diffusion system of claim 7 , wherein the mixer comprises a top, a bottom opposite the top, and a sidewall therebetween, wherein the longitudinal groove is formed into the sidewall extending from the top of the mixer to the bottom of the mixer.

9. The diffusion system of claim 5 , wherein the mixer comprises a top, a bottom opposite the top, and a sidewall therebetween, wherein the top of the mixer comprises an irregularity.

10. The diffusion system of claim 9 , wherein the irregularity is a transverse groove.

11. The diffusion system of claim 5 , wherein the mixer comprises a top, a bottom opposite the top, and a sidewall therebetween, wherein the bottom of the mixer comprises a downward projection.

12. A diffusion system, comprising:
a. a cell for receiving a receptor medium;
b. a mixer configured to fit inside the cell to mix the receptor medium in the cell;
c. a cell cap to cover the cell;
d. a dosage lid to place on top of the cell cap; and
e. a heating and stirring system, wherein the heating and stirring system comprises a dry heat block, the dry heat block comprising a plurality of bays to receive a plurality of cells, each bay comprising a stirrer configured to rotate the mixer.

13. The diffusion system of claim 12 , wherein each bay of the dry heat block is defined by a cylindrical wall having an inner diameter.

14. The diffusion system of claim 13 , wherein each bay of the dry heat block defines a slot to accommodate an arm of the cell when the cell is inserted into one of the bays.

15. The diffusion system of claim 14 , wherein the heating and stirring system further comprises a sleeve insertable into any one of the plurality of bays, such that heat generated in the bay into which the sleeve has been inserted is transferred to the sleeve.

16. The diffusion system of claim 12 , wherein the stirrer comprises a rotatable magnet mounted in a cup.

17. The diffusion system of claim 12 , further comprising a controller running on an embedded single-board computer to control the heat generated by the heating and stirring system and to control the stirrer.

18. A diffusion system, comprising:
a. a cell for receiving a receptor medium;
b. a mixer configured to fit inside the cell to mix the receptor medium in the cell;
c. a cell cap to cover the cell;
d. a dosage lid to place on top of the cell cap; and
e. an automated sampling and collection station, wherein the automated sampling and collection station comprises a syringe driven probe configured to move in three translational directions.

19. The diffusion system of claim 18 , wherein the probe is mounted on a rotatable head that allows the probe to tilt between a vertical orientation and an angled orientation.

20. The diffusion system of claim 19 , wherein the automated sampling and collection station comprises a peg, wherein coordinated movement of the probe relative to the peg allows the peg to tilt the probe between the vertical orientation and the angled orientation.

21. The diffusion system of claim 20 , wherein the automated sampling and collection station further comprises a collection tray, wherein the probe is configured to:
a. move to the peg and use the peg to tilt the probe in the angled orientation;
b. move to the cell and insert into an angled sampling arm of the cell to extract a sample from the receptor medium;
c. move to the peg and use the peg to tilt the probe in the vertical orientation; and
d. move to the collection tray and deposit the extracted sample into a collection vial mounted on the collection tray.

22. The diffusion system of claim 21 , wherein the automated sampling and collection station further comprises a wash station, wherein the probe is configured to move to the wash station after depositing the extracted sample into the collection vial and wash the probe in preparation for another extraction.

Assignees

• Teledyne Instruments Inc

Inventors

• Shaw Steven W
• Downes Gary C

Classifications

• G01N13/00 Primary

  Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects (scanning-probe techniques or apparatus G01Q) · CPC title

• G01N2035/00356

  Holding samples at elevated temperature (incubation) · CPC title

• G01N15/08

  Investigating permeability, pore-volume, or surface area of porous materials · CPC title

• G01N2035/00534

  Mixing by a special element, e.g. stirrer · CPC title

• G01N2013/006

  Dissolution of tablets or the like · CPC title