Weight difference inspection method of tablet drug analysis technology

Tablets are made by mixing the drug and excipients and then compressed. It is a common oral drug. When analyzing and testing tablet drugs, in order to ensure the uniform quality characteristics of the drug, a weight difference check is required. The uniformity of a drug means that each unit product of a drug preparation meets the requirements of effectiveness and safety. Since people take medicines according to the unit dose, if the content of each unit is not uniform, it may cause insufficient dosage or excessive dosage, which may cause poisoning or even death. Therefore, for tablets, injections, and granules of pharmaceutical preparations And syrups must have the same quality.

There are many types of tablets, such as dispersible tablets, effervescent tablets, enteric-coated tablets, sustained-release tablets, controlled-release tablets, buccal tablets, chewable tablets, dispersible tablets and sugar-coated tablets, etc. The biggest advantage is the dosage Accurate, stable physical and chemical properties, long storage period and low price.

Generally, the steps of tablet drug analysis and testing are firstly to check its appearance, color, odor, etc., and then conduct identification test; secondly, conduct routine inspection and impurity analysis, as well as bacterial count, mold count and biopsy, and finally content Determination. Medicilon Pharmaceutical Analysis provides a full range of drug analysis services, including method development and method validation, analytical testing and release, stability studies, large-scale separation and CMC filing services.

In the production process of tablets, due to the uniformity, fluidity, technology, production equipment and other reasons of the particles, there will be a certain deviation in the weight between the tablets. If it exceeds or is less than the limit, it is difficult to guarantee the clinical use of drugs. Accurate dosage, so the weight difference of tablets should be checked. The weight difference refers to the degree of difference between the weight of each piece and the average piece weight measured by the weighing method.

The weight difference check refers to randomly taking a certain number of samples from a whole, and comparing how close the weight of each sample is to the average value of the sample, which can also be understood as the degree of dispersion. According to the description of the Chinese Pharmacopoeia, take the tablet as an example, take 20 test samples, accurately weigh the total weight, and calculate the average tablet weight, then accurately weigh each tablet; the weight of each tablet is compared with the average tablet weight For tablets without content determination, the weight of each tablet should be compared with the weight of the labeled tablet. According to the limit of the weight difference inspection method, the limit of weight difference should not exceed 2 tablets, and no one tablet should exceed the limit by 1 time.

The limits of the weight difference limit method Average film weight or label film weight To Weight difference limit 0.30g or less To ±7.5% 0.30g and above 0.30g To ±5%

When using the weight difference measurement method, you should wear gloves or finger cots, or use flat-tipped tweezers to take the tablets, and do not directly touch the test product with your hands. In addition, the test product that is easy to absorb moisture should be placed in a closed weighing bottle and weighed as soon as possible.

The weight difference inspection method converts the weight of each piece according to the average weight and the actually measured content, calculates the percentage content of each piece virtually, and then evaluates it according to the idea of ​​content uniformity, which can control the dispersion and also The degree of deviation can be controlled, and it can prevent production enterprises from carrying out low-limit feeding or crude production technology. The rigorous and scientific standard is to control the quality of drugs, promote the excellence of the production process, and improve the company’s own technical content, and to achieve the ultimate guarantee of improving the intrinsic quality of drugs. Therefore, it is very important to formulate a strict weight difference inspection method.

At the same time, it should be noted that not all tablets can be taken apart when taking tablets. Generally split tablets and dispersible tablets can be taken separately, but enteric-coated tablets, sustained-release tablets, and control tablets must be swallowed as a whole. This is because the outer layer of enteric-coated tablets is coated with a gastric-resistant coating to prevent Stomach acid is digested in advance to ensure that the medicine can be absorbed after entering the intestine. Sustained-release tablets can release the drug slowly, while controlled-release tablets can release the drug at a constant rate. If such drugs are broken, the controlled-release film of the tablet will be destroyed, and the drug will be released quickly, failing to achieve sustained and long-term release. For the purpose of effectiveness, in severe cases, it may even cause drug poisoning in patients due to a rapid increase in drug concentration.