How to Perform a Standardized Tapped Density Test for Pharmaceutical Powders
2021-11-09Application Note
BeDensi T Pro Series (3-workstation) measures tapped density for QbD/GMPs. It meets USP/Ph. Eur. standards, ensuring repeatable powder analysis.
| Product | BeDensi T Pro Series |
| Industry | Pharmaceuticals |
| Sample | Lactose, Mannitol, Microcrystalline cellulose |
| Measurement Type | Powder Characteristics |
| Measurement Technology |
Jump to a section:
Abstract: Tapped density is a significant parameter to explore the compressibility and flowability of pharmaceutical powders, which is useful to promote the approach of QbD and GMPs. Standardization of apparatus and procedure is vital to get meaningful, repeatable results. In this application note, standardized tapped density tests of three excipients were performed by the BeDensi T3 Pro with 3 workstations. It is worthy of note that this highly efficient and economic tester is designed to meet the USP and Ph. Eur. standards fully.
Key words: Tapped Density; Pharmaceutical Powders; Flowability; Compressibility; Hausner Ratio.
1. Introduction
Pharmaceutical powders are mainly composed of active pharmaceutical ingredients (API) and excipients, and presented to the patient in the form of solid dosages such as granules, tablets, and capsules. Powders that have all the right attributes can be deemed to have good compressibility, suitable to be made into tablets by compression in a tableting press. The flow properties of the powders are the key to the success of many pharmaceutical operations, including tableting and capsule filling. Those powders with the appropriate flow properties promote the homogeneity of the API and excipient bulk easily. Knowing these properties is useful to promote the approach of Quality by Design (QbD) and good manufacturing practices (GMPs) for pharmaceutical products and processes.
Tapped density (volume) is one of the necessary parameters needed to calculate the compressibility index (CI) or Hausner ratio (HR), which relate to the flow characteristics of the pharmaceutical powders. Tapped density (Ptapped) of a powder is the ratio of the mass of powder (M) to the volume (VF) occupied by powder after it has been tapped for a defined period. The tapped densities of samples are calculated by using the following equation:
Due to its simplicity and convenience, the tapped density test is a popular method to understand powder flow properties. The test recommended by the European Pharmacopoeia (Ph. Eur..) and the United States Pharmacopoeia (USP) has been harmonized. To this end, standardization of the apparatus and procedure has been stipulated in order to attain vital, meaningful results.
This application note aims to perform a standardized tapped density test of excipients according to USP and Ph. Eur. standards.
2. Standardized Test
2.1 Apparatus
The BeDensi T Pro series, which complies fully with the Ph. Eur. and USP standards, can help you to perform standardized tests of tapped density easily. [1, 2] In addition, user-defined measurements are also supported.
| USP & Ph. Eur. Standards | Methods I | Methods I / II | BeDensi T Pro Series | |||
| Cylinder | Volume (mL) | 250 |
25
|
100 | 250 | |
| Mass (g) |
220±44
|
55±10
|
140±10
|
210±10
|
||
| Height (mm) |
≤335
|
155±10
|
245±10
|
237±10
|
||
| Tap | Height (mm) |
14±2
|
3±0.2
|
3±0.2 or 14±2
|
||
| Speed (taps / min) |
300±15
|
250±15
|
100-300 (adjustable)
|
|||
Learn more details about Bettersize BeDensi T Pro
2.2 Test Procedure
The tapped volume of three common excipients (microcrystalline cellulose MCC, lactose, and mannitol) was obtained using the BeDensi T3 Pro with 3 workstations by the USP method Ⅰ. The procedure is shown in the following schematic. To conform to the volume requirement (≥60% of 250 ml cylinder volume) of USP or Ph. Eur., 75 g MCC, 120 g lactose, and 120 g mannitol were used. Until the difference between succeeding test volumes (ΔV) is less than or equal to 2 mL, the latter is the tapped volume. After inputting the tapped volume and the mass value, the BeDensi T Pro will calculate the tapped density automatically. Then, the CI and HR were also calculated according to the following formula:
Where V0 is the unsettled volume and VF is the tapped volume.
3. Results
The volumes of the three samples were obtained by the BeDensi T3 Pro under different taps. As shown in the figure, the volume decreased with an increasing number of taps. When the number of taps reached 500, the change in volume only decreased slightly. The V2000 is the tapped volume for MCC, and V1250 is the tapped volume for lactose and mannitol. The bulk density, tapped density, CI, and HR were confirmed as shown in Table 2. On the basis of the relationship between the CI/HR and the flowability [3], the flow behavior of these excipients was determined. Comparing the MCC and mannitol, the lactose has the poorest flowability in this case.
4. Conclusion
By employing the BeDensi T3 Pro, standardized tests of tapped density were performed to study the tapped density of three pharmaceutical powders. The tapped volume and tapped density of these samples were determined easily and scientifically. To obtain meaningful and valuable results for evaluating the flowability, a reliable tapped density tester- the BeDensi T Pro series- is necessary to provide a standardized tapped density test.
5. Reference
[1] USP <616>, Bulk Density and Tapped Density of Powders
[2] Ph. Eur. 2.9.34. Bulk Density and Tapped Density of Powders
[2] USP <1174> Powder Flow
About the Authors
 |
Perfil Liu Engineer @ Application Research Lab, Bettersize Instruments Ltd.
|
|
The BeDensi T Pro Series is a reliable tapped density tester. It excels at intuitive operation while complying with the USP, Ph. Eur., ASTM, and ISO standards.
|
|
Recommended articles
Rate this article