Determination of the solubility of acetaminophen tablets.

, the purpose of the
1. Mastering the determination of tablet solubility
2. Can correctly use the solubility meter 2, experimental guidance
tablets and other solid preparations to take, in the gastrointestinal tract to go through the dissolution and dissolution of the two processes, before it can be absorbed through the biofilm. For many drugs, the absorption is usually directly equivalent to the amount the drug dissolves from the dosage form. For insoluble drugs, dissolution is the main process, so the time limit of dissolution is often not used as an indicator to judge the absorption degree of insoluble drug preparations.
with a solubility of less than 0.1 to 1.0 (g/L), the absorption in the body is often affected by its dissolution rate. In addition to the crystal type and particle size of the drug, the speed of dissolution is also related to the production process, accessories, storage conditions and so on. In order to effectively control the quality of solid preparations, in addition to the in vivo measurement method such as blood drug concentration method or urine drug concentration method to guess the absorption speed, in vitro solubility determination method is a simpler
seed quality control
method.is the speed and degree at which a drug dissolves from a solid preparation, such as a tablet or capsule, in a specified solvent. However, in practical application, the degree of dissolution only refers to the degree of drug dissolution within a certain period of time, generally expressed as a percentage of the indicated amount, such as the pharmacopeia within 30 minutes of the limit of the dissolution of acetaminophen is 80% of the indicated amount.For oral solid preparations, especially for insoluble solid preparations that are poorly absorbed in the body, and for solid preparations for drugs that are close to the toxic dose, the solubility test should be performed and used as a quality standard.3, the experimental content
(1) the basketball method instrument device
1. Basket basket body and basket shaft two parts, are made of stainless steel metal. The inner diameter of stainless steel wire mesh is 22.2mm ± 1.0mm, and the range of the basket should not exceed 1.0mm ± the rotation.
2. The operating container is a round bottom of 1000 ml
Bea cup
, coat water bath, the temperature of the water bath should be able to keep the temperature of the solvent in the container at 37 degrees C ±0.5 degrees C. The bottom of the basket is 25mm away from the bottom of the be ± 2mm.
3. The motor is connected to the basket shaft, and the speed can be adjusted at any speed of 50 to 200 rets per minute, with a steady speed error of not more than ±4%.
4. The instrument should be equipped with 6 sets of operating devices, which can be used to determine 6 tests at a time. The sampling point position should be in the middle of the end-to-end solution on the basket, 10mm from the beech wall.(ii) determination of the solubility of acetaminophen tablets
1. With 24 ml of thin hydrochloric acid plus degassed water to 1000 ml as the solvent, the amount of 1000 ml solvent is injected into each operating container, and the heating keeps the solvent temperature at 37±0.5 degrees C. Adjust the basket speed to 100 rets per minute and stabilize it.
2. Take 6 pieces for test products, respectively, into 6 baskets, the basket will be lowered into the container, immediately start timing. After 30 minutes, take the solution 5 ml, filter, precision amount to continue the filter 1 ml, plus 0.04% sodium hydroxide solution diluted to 50 ml, shake well, light ionizing light method, at 257nm wavelength to determine absorption, according to C8H9NO2 absorption score (E1%1cm) for 715 to calculate the amount of each piece of dissolved. The limit is 80% of the indicated amount and shall be in accordance with the regulations.(iii) Results Judge
The amount of dissolved in each of the 6 tablets shall not be lower than the prescribed limit (Q) according to the indicated content, unless otherwise specified, the limit (Q) shall be 70% of the indicated content. If only 1 of the 6 tablets is below the prescribed limit, but not less than Q to 10%, and the average amount of dissolved is not less than the prescribed limit, it can still be judged to be in compliance with the provisions. If 1 of the 6 tablets is lower than Q to 10%, another 6 tablets should be taken for retry, and only 2 of the 12 tablets of the initial and retry are below Q to 10%, and their average amount of dissolved is not less than the prescribed limit, it can also be judged to meet the provisions..note
1. Dissolved instrument water bath should be added purified water to the water line, after power-on water should be recycled.
2. The solution has been filtered with a micro-porous membrane not greater than 0.8 m, and self-sampling to filtering should be completed within 30 seconds., thinking question 1.
1. Why do tablets or capsules of some drugs need to be solubility determined?
2. What problems should be paid attention to in the experimental process in order to make the solubility determination results accurate?
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