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2040 DISINTEGRATION AND DISSOLUTION OF DIETARY SUPPLEMENTS

DISINTEGRATION
This test is provided to determine compliance with the limits on Disintegration stated below or in the individual class monographs on dietary supplements, including botanical dosage forms. This test applies to uncoated and plain coated tablets and to hard gelatin and soft gelatin capsules. It does not apply to tablets or capsules designed to liberate vitamin or mineral content over an extended period or where the label states that the dosage form is to be chewed. Determine the type of units under test from the labeling and from observation, and apply the appropriate procedure to 6 or more dosage units.
For the purposes of this test, disintegration does not imply complete solution of the unit or even of its active constituent. Complete disintegration is defined as that state in which any residue of the unit, except fragments of insoluble coating or capsule shell, remaining on the screen of the test apparatus is a soft mass having no palpably firm core.
Apparatus
Apparatus A— Use the Apparatus described under Disintegration 701 for tablets or capsules that are not greater than 18-mm long. For larger tablets or capsules, use Apparatus B.
Apparatus B— The apparatus* consists of a basket-rack assembly, a 1000-mL, low-form beaker for the immersion fluid, a thermostatic arrangement for heating the fluid between 35 and 39, and a device for raising and lowering the basket in the immersion fluid at a constant frequency rate between 29 and 32 cycles per minute through a distance of not less than 5.3 cm and not more than 5.7 cm. The volume of the fluid in the vessel is such that at the highest point of the upward stroke the wire mesh remains at least 2.5 cm below the surface of the fluid and descends to not less than 2.5 cm from the bottom of the vessel on the downward stroke. The time required for the upward stroke is equal to the time required for the downward stroke, and the change in stroke direction is a smooth transition, rather than an abrupt reversal of motion. The basket-rack assembly moves vertically along its axis. There is no appreciable horizontal motion or movement of the axis from the vertical.
Basket-Rack Assembly— The basket-rack assembly consists of three open-ended transparent tubes, each 7.95- ± 0.05-cm long and having an inside diameter of approximately 33.3-mm and a wall approximately 2.4 mm thick; the tubes are held in a vertical position by two plastic plates, each about 9.7 cm in diameter and 9.5 mm in thickness, with three holes, each about 39 mm in diameter, equidistant from the center of the plate and equally spaced from one another. Attached to the under surface of the lower plate is 10-mesh No. 23 (0.025-inch) W. and M. gauge woven stainless-steel wire cloth having a plain square weave. The parts of the apparatus are assembled and rigidly held by means of three bolts passing through the two plastic plates. A suitable means is provided to suspend the basket-rack assembly from the raising and lowering device using a point on its axis.
The design of the basket-rack assembly may be varied somewhat provided the specifications for the glass tubes and the screen mesh size are maintained.
Disks— Each tube is provided with a perforated cylindrical disk 15.3- ± 0.15-mm thick and 31.4 ± 0.13 mm in diameter. The disk is made of a suitable, transparent plastic material having a specific gravity of between 1.18 and 1.20. Seven 3.2-mm holes extend between the ends of the cylinder, one of the holes being through the cylinder axis and the others parallel with it equally spaced on a 6-mm radius from it. All surfaces of the disk are smooth.
Procedure
VITAMIN-MINERAL DOSAGE FORMS
Uncoated Tablets and Film-Coated Tablets— Place 1 tablet in each of the tubes of the basket, add a disk to each tube, and operate the apparatus, using water maintained at 37 ± 2 as the immersion fluid. At the end of 30 minutes, lift the basket from the fluid, and observe the tablets: all of the tablets disintegrate completely. If 1 or 2 tablets fail to disintegrate completely, repeat the test on 12 additional tablets: not fewer than 16 of the total of 18 tablets tested disintegrate completely.
Plain Coated Tablets (Other Than Film-Coated Tablets)— Place 1 tablet in each of the tubes of the basket and, if the tablet has a soluble external coating, immerse the basket in water at room temperature for 5 minutes. Then add a disk to each tube, and operate the apparatus, using water maintained at 37 ± 2 as the immersion fluid. After 45 minutes of operation in water, lift the basket from the fluid, and observe the tablets: all of the tablets have disintegrated completely. If 1 or 2 tablets fail to disintegrate completely, repeat the test on 12 additional tablets: not fewer than 16 of the total of 18 tablets tested disintegrate completely.
Hard Gelatin Capsules— Apply the test for Uncoated Tablets, using 0.05 M acetate buffer, prepared by mixing 2.99 g of sodium acetate trihydrate and 1.66 mL of glacial acetic acid with water to obtain 1000 mL of solution having a pH of 4.50 ± 0.05, maintained at 37 ± 2 as the immersion fluid. At the end of 45 minutes, lift the basket from the fluid, and observe the capsules: all of the capsules disintegrate except for fragments from the capsule shell. If 1 or 2 capsules fail to disintegrate completely, repeat the test on 12 additional capsules: not fewer than 16 of the total of 18 capsules tested disintegrate completely.
Soft Gelatin Capsules— Proceed as directed under Hard Gelatin Capsules.
BOTANICAL DOSAGE FORMS
Uncoated Tablets and Film-Coated Tablets— [NOTE—Omit the use of disks unless otherwise specified in the individual monograph.] Place 1 tablet in each of the tubes of the basket, and operate the apparatus, using water maintained at 37 ± 2 as the immersion fluid. At the end of 20 minutes, lift the basket from the fluid, and observe the tablets: all of the tablets disintegrate completely. If 1 or 2 tablets fail to disintegrate completely, repeat the test on 12 additional tablets: not fewer than 16 of the total of 18 tablets tested disintegrate completely.
Plain Coated Tablets (other than Film-Coated Tablets)— [NOTE—Omit the use of disks, unless otherwise specified in the individual monograph.] Place 1 tablet in each of the tubes of the basket and, if the tablet has a soluble external coating, immerse the basket in water at room temperature for 5 minutes. Operate the apparatus using water maintained at 37 ± 2 as the immersion fluid. After 20 minutes of operation in water, lift the basket from the fluid, and observe the tablets: all of the tablets have disintegrated completely. If 1 or 2 of the tablets fail to disintegrate completely, repeat the test on 12 additional tablets: not fewer than 16 of the total of 18 tablets tested disintegrate completely.
Delayed-Release (Enteric-Coated) Tablets— Place 1 tablet in each of the six tubes of the basket, and if the tablet has a soluble external coating, immerse the basket in water at room temperature for 5 minutes. Then operate the apparatus using simulated gastric fluid TS maintained at 37 ± 2 as the immersion fluid. After 1 hour of operation in simulated gastric fluid TS, lift the basket from the fluid, and observe the tablets: the tablets show no evidence of disintegration, cracking, or softening. Operate the apparatus, using simulated intestinal fluid TS, maintained at 37 ± 2 as the immersion fluid, for the time specified in the monograph. Lift the basket from the fluid, and observe the tablets: all of the tablets disintegrate completely. If 1 or 2 tablets fail to disintegrate completely, repeat the test on 12 additional tablets: not fewer than 16 of the total of 18 tablets tested disintegrate completely.
Hard Gelatin Capsules— Apply the test for Uncoated Tablets, using 0.05 M acetate buffer, prepared by mixing 2.99 g of sodium acetate trihydrate and 1.66 mL of glacial acetic acid with water to obtain 1000 mL of solution having a pH of 4.50 ± 0.05, maintained at 37 ± 2 as the immersion fluid. At the end of 20 minutes, lift the basket from the fluid, and observe the capsules: all of the capsules disintegrate except for fragments from the capsule shell. If 1 or 2 capsules fail to disintegrate completely, repeat the test on 12 additional capsules: not fewer than 16 of the total of 18 capsules tested disintegrate completely.
Soft Gelatin Capsules— Proceed as directed under Hard Gelatin Capsules.

DISSOLUTION
Vitamin–Mineral Dosage Forms
This test is provided to determine compliance with the dissolution requirements where stated in the individual class monographs for a tablet or capsule dosage form, except where the label states that the tablets are to be chewed. It does not apply to tablets or capsules designed to release vitamin or mineral content over a delayed or extended period of time. Soft gelatin capsule preparations of dietary supplements meet the requirements for Disintegration.
All dietary supplements belonging to USP Classes II to VI, prepared as tablets or capsules, are subject to the dissolution test and criteria described in this chapter for folic acid (if present) and for index vitamins and index minerals. This test is also required if the product labeling includes a health claim concerning the relationship between folate deficiency and the risk of neural tube defects. The accompanying table lists the dissolution requirements for the individual USP classes of dietary supplements. Class I dietary supplements are combinations of oil-soluble vitamins, which are exempt from dissolution requirements; hence, dissolution requirements do not apply to the oil-soluble vitamins contained in formulations belonging to Class IV or Class V.
Dietary Supplements—Vitamin–Mineral
Dosage Forms
USP
Class
Combination of
Vitamins or Minerals
Present
Dissolution Requirement
I Oil-Soluble Vitamins not applicable
II Water-Soluble Vitamins one index vitamin; folic
acid (if present)
III Water-Soluble Vitamins
with Minerals
one index vitamin and
one index element;
folic acid (if present)
IV Oil- and Water-Soluble
Vitamins
one index water-soluble
vitamin; folic acid
(if present)
V Oil- and Water-Soluble
Vitamins with
Minerals
one index water-soluble
vitamin and one
index element; folic
acid (if present)
VI Minerals one index element
Unless otherwise stated in the individual monograph, test 6 dosage units for dissolution as directed under Dissolution 711.
DISSOLUTION CONDITIONS FOR FOLIC ACID
NOTE—Perform this test under subdued light.
Medium: water; 900 mL. If the units tested do not meet the requirements for dissolution in water, test 6 additional dosage units for dissolution in a medium of 900 mL of 0.05 M pH 6.0 citrate buffer solution, prepared by mixing 9.5 mL of 0.1 M citric acid monohydrate and 40.5 mL of 0.1 M sodium citrate dihydrate in a 100-mL volumetric flask, diluting with water to volume, mixing, and adjusting to a pH of 6.0 by using either 0.1 M hydrochloric acid or 0.1 M sodium hydroxide solution.
Apparatus 1: 100 rpm, for capsules.
Apparatus 2: 75 rpm, for tablets.
Time: 1 hour.
DISSOLUTION CONDITIONS FOR INDEX VITAMINS and INDEX MINERALS
Medium: 0.1 N hydrochloric acid; 900 mL.
Apparatus 1: 100 rpm, for capsules.
Apparatus 2: 75 rpm, for tablets.
Time: 1 hour.
For formulations containing 25 mg or more of the index vitamin, riboflavin, use the following conditions:
Medium: 0.1 N hydrochloric acid; 1800 mL.
Apparatus 1: 100 rpm, for capsules.
Apparatus 2: 75 rpm, for tablets.
Time: 1 hour.
SELECTION OF INDEX VITAMINS and INDEX ELEMENTS
Compliance with the dissolution requirements for dietary supplements representing combinations of water-soluble vitamins (Water-Soluble Vitamins Capsules and Water-Soluble Vitamins Tablets) and combinations of oil- and water-soluble vitamins (Oil- and Water-Soluble Vitamins Capsules and Oil- and Water-Soluble Vitamins Tablets) is determined by measuring the dissolution of a single index vitamin from the water-soluble vitamins present. Riboflavin is the index vitamin when present in the formulation. For formulations that do not contain riboflavin, pyridoxine is the index vitamin. If neither riboflavin nor pyridoxine is present in the formulation, the index vitamin is niacinamide (or niacin), and in the absence of niacinamide (or niacin), the index vitamin is thiamine. If none of the above four water-soluble vitamins is present in the formulation, the index vitamin is ascorbic acid.
Compliance with the dissolution requirements for dietary supplements representing combinations of minerals (Minerals Capsules and Minerals Tablets) is determined by measuring the dissolution of only one index element. Iron is the index element when present in the formulation. For formulations that do not contain iron, the index element is calcium. If neither iron nor calcium is present, the index element is zinc, and in the absence of all three of these elements, magnesium is the index element.
Compliance with dissolution requirements for dietary supplements representing combinations of water-soluble vitamins and minerals (Water-Soluble Vitamins with Minerals Capsules and Water-Soluble Vitamins with Minerals Tablets) and combinations of oil- and water-soluble vitamins and minerals (Oil- and Water-Soluble Vitamins with Minerals Capsules and Oil- and Water-Soluble Vitamins with Minerals Tablets) is determined by measuring the dissolution of one index water-soluble vitamin and one index element, designated according to the respective hierarchies described above.
PROCEDURES
In the following procedures, combine equal volumes of the filtered solutions of the 6 individual specimens withdrawn, and determine the amount of folic acid or the index vitamin or element dissolved, based on the average of 6 units tested. Make any necessary modifications including concentration of the analyte in the volume of test solution taken. Use Dissolution Medium for preparation of the Standard solution and dilution, if necessary, of the test solution.
Folic Acid— Determine the amount of C19H19N7O6 dissolved by employing the procedure set forth in the Assay for folic acid under Oil- and Water-Soluble Vitamins with Minerals Tablets, in comparison with a Standard solution having a known concentration of USP Folic Acid RS in the same medium.
Niacin or Niacinamide, Pyridoxine, Riboflavin, and Thiamine— Determine the amount of the designated index vitamin dissolved by employing the procedure set forth in the Assay for niacin or niacinamide, pyridoxine, riboflavin, and thiamine under Water-Soluble Vitamins Tablets.
Ascorbic Acid— Determine the amount of C6H8O6 dissolved by adding 10 mL of 1.0 N sulfuric acid and 3 mL of starch TS to 100.0 mL of test solution, and titrating immediately with 0.01 N iodine VS. Perform a blank determination, and make any necessary correction.
Iron, Calcium, Magnesium, and Zinc— Determine the amount of the designated index element dissolved by employing the procedure set forth in the appropriate Assay under Minerals Capsules.
TOLERANCES
The requirements are met if not less than 75% of the labeled content of folic acid and not less than 75% of the labeled content of the index vitamin or the index element from the units tested is dissolved in 1 hour.
Botanical Dosage Forms
This test is provided to determine compliance with the dissolution requirements where stated in the individual monograph for a tablet or capsule dosage form. See Dissolution 711 for description of apparatus used, Apparatus Suitability Test, and other related information. Of the types of apparatus described in 711, use the one specified in the individual monograph. Where the label states that an article is enteric-coated, and a dissolution or disintegration test that does not specifically state that it is to be applied to enteric-coated articles is included in the individual monograph, the test for Delayed-Release Articles under Drug Release 724 is applied, unless otherwise specified in the individual monograph. Compliance with dissolution requirements is determined by testing 6 dosage units individually, or testing 2 or more counted number of dosage units in each vessel, and measuring the dissolution of one or more index/marker compound(s) or the extract specified in the individual monograph. This nonspecific dissolution is intended to be diagnostic of known technological problems that may arise due to coatings, lubricants, disintegrants, and other substances inherent in the manufacturing process. Further, this dissolution measurement allows an assessment of the extent of decomposition of the extract to polymeric or other nondissoluble compounds that may have been produced by excessive drying or other manipulations involved in the manufacture of botanical extracts. The operative assumption inherent in this procedure is that if the index or marker compound(s) or the extract is demonstrated to have dissolved within the time frame and under conditions specified, the dosage form does not suffer from any of the above formulation or manufacturing related problems.
PROCEDURES
Combine equal volumes of the filtered solutions of the 6 or more individual specimens withdrawn, and use the pooled sample as the test solution. Determine the average amount of index or marker compound(s) or the extract dissolved in the pooled sample by the Procedure specified in the individual monograph. Make any necessary modifications, including concentration of the analyte in the volume of the test solution taken. Use Dissolution Medium for preparation of the Standard solution and dilution, if necessary, of the test solution.
INTERPRETATION
Pooled Sample— Unless otherwise specified in the individual monograph, the requirements are met if the quantities of the index or marker compound(s) or the extract dissolved from the pooled sample conform to the accompanying acceptance table. The quantity, Q, is the amount of dissolved index or marker compound(s) or the extract specified in the individual monograph, expressed as a percentage of the labeled content. The 5%, 15%, and 25% values in the acceptance table are percentages of the labeled content so that these values and Q are in the same terms.
Acceptance Table for a Pooled Sample
Stage Number Tested Acceptance Criteria
S1 6 Average amount dissolved is not
less than Q + 10%
S2 6 Average amount dissolved
(S1 + S2) is equal to
or greater than Q + 5%
S3 12 Average amount dissolved
(S1 + S2 + S3) is equal
to or greater than Q

*  An apparatus and disks meeting these specifications are available from VanKel Technology Group, 13000 Weston Parkway, Cary, NC 27513, or from laboratory supply houses.

Auxiliary Information—
Staff Liaison : Damian A. Cairatti, M.Sc., Senior Scientific Associate
Expert Committee : (DSBA05) Dietary Supplements - Bioavailability
USP29–NF24 Page 3089
Pharmacopeial Forum : Volume No. 29(2) Page 513
Phone Number : 1-301-816-8307