Accurate weighing is one of the key tasks carried out in a pharmaceutical quality control laboratory. It is important to ensure that the results are valid and reliable. New pharmaceutical regulations are helping to close the gap between outdated strategies for quality management in weighing and established metrological concepts.
Process weighing involves measuring and controlling powder materials in production processes. This can include level or inventory monitoring, bag or drum filling and dispensing, and simultaneous blending of ingredients.
Pre-weighing
An automated weighing process offers a range of benefits to manufacturers, including improved product quality and greater efficiency. It can also help reduce raw material losses and rework, boosting profitability. However, successful transition to weigh batching requires a thoughtful plan. It is crucial to fully assess current processes, identify inefficiencies and gaps, and choose a system that will meet specific needs.
Many industrial weighing systems incorporate pre-weighing, which allows an operator to check-weigh ingredients before discharge into the process vessel. This is particularly important with loss-of-weight systems that use blenders or other process vessels on load cells for weighing, and where an out-of-specification ingredient could ruin the entire batch.
Pre-weigh lines, such as the OPDosing Linear Palamatic Process weighing line, are ideal for producers who pre-weigh a large number of ingredients in a recipe. These lines offer a convenient, ergonomic manual dosing unit for operators and include an integrated mobile scale to provide weighing preparers with an efficient workstation. They can also be connected to a LIMS for data tracking and traceability.
Balance validation
The quality of your weighing results depends on the accuracy of the balance/scale. This is why it is important to perform regular balance/scale tests. These checks can identify problems that may not be visible when the equipment is in use. This saves time and money by preventing inaccurate results from going undetected until your next service calibration.
During a verification test, a weight (usually 50% of the maximum capacity of the balance) is weighed at various locations on the weighing pan and the mean measurement and relative standard deviation are calculated. A satisfactory result is a RSD of no more than 0.05%.
In some cases, the balance can be internally calibrated using built-in calibration weights or other algorithms. This process is usually conducted daily or before critical measurements, and is particularly necessary after significant changes in environmental factors like temperature fluctuations or air pressure. This process is normally performed in a sealed environment, reducing the risk of contamination from dust or particulates.
Direct weighing
If you’re dealing with non-hygroscopic solid samples or reagents that are stable in air, direct weighing is an option. To perform this process, start by accurately weighing the clean pan of your balance and record its mass reading (this is called taring).
When you’re ready to weigh your sample, cover it with spun gauze gloves, finger cots or wrap it in paper strips, and place it on the balance pan. Alternatively, you can also use an Erlenmeyer flask or beaker to hold the sample. Then, put the weighed bottle on the scales and pour out the sample until you’ve reached the desired mass.
This method is highly accurate and eliminates the need for additional equipment, which can be expensive. It’s also more efficient than manual weighing, and can save businesses money by reducing raw material waste and rework. Moreover, it can help to maintain product consistency and quality, which is crucial for industries like pharmaceutical manufacturing.
Order of ingredients
The weighing process is integral to many industries, from making medication to building bridges. Weighing gives us a precise quantification of the matter that makes up various objects and materials, allowing us to transport, record, and use them more efficiently. It is also crucial in ensuring that manufacturers comply with strict quality standards and regulations.
Balance validation is a critical step in the weighing process that confirms the accuracy of a scale and ensures consistent results. This is especially important in highly sensitive industries, like food and pharmaceuticals, where precision is essential.
An automated weighing system is a powerful tool for manufacturing and inventory management. These systems are capable of pre-weighing and determining the order of ingredients automatically, streamlining operations and eliminating bottlenecks. They can also scan barcodes and connect to a database, allowing for quick access to product details and traceability. They are also often equipped with features for batch manufacturing and compliance monitoring.