Understanding Porosity in Tablets with the Microtrac BELSORP

May 28, 2025

In the pharmaceutical industry, the smallest details matter, especially when it comes to the design and performance of tablets. One of these critical details is porosity, the measure of how much empty space (pores) exists within a solid structure. Understanding and controlling porosity is essential because it directly affects how a tablet dissolves and how it delivers medication.

That's where the BELSORP series from Microtrac, distributed in Canada by ATS Scientific Inc. comes into play. This advanced line of gas adsorption analyzers provides pharmaceutical scientists with the tools they need to accurately measure porosity in a reliable and reproducible way.

Why Is Porosity Important in Pharmaceutical Tablets?

Porosity plays a major role in how a tablet behaves once it reaches the human body. Here are just a few reasons why it's critical:

Drug Dissolution Rate: Higher porosity often means a faster dissolution rate, which can be essential for drugs that need to act quickly.
Mechanical Strength: Porosity impacts tablet hardness. Too much porosity can lead to fragile tablets.
Stability and Shelf Life: Moisture can get trapped in pores, potentially affecting the chemical stability of the drug.
Controlled Release: In extended-release formulations, porosity must be precisely engineered to release the active ingredient over time.

What is the BELSORP Series?

The BELSORP series is a group of high-precision gas adsorption analyzers designed for measuring pore size distribution and pore volume of materials. In pharmaceutical applications, these metrics are essential for characterizing porous structures such as tablets, powders, and excipients.

Models like the BELSORP Mini X, BELSORP Max X, and BELSORP Max II offer various levels of automation and throughput, but all use gas adsorption techniques, most often nitrogen at 77K, to analyze samples with extremely high precision.

How Does the BELSORP Determine Porosity?

The BELSORP series uses a technique known as gas adsorption porosimetry. Here’s how it works:

Sample Preparation: The pharmaceutical tablet is first degassed to remove moisture and contaminants
Gas Introduction: A known amount of inert gas is introduced in the sample at controlled pressures
Adsorpotion Measurement: The gas molecules adsorb to the surface of the sample, including with its pores
Data Analysis: By measuring how much gas is adsorbed at various pressures the system calculates:

Surface Area
Pore volume
Pore size distribution (via BJH or DFT methods)

This non-destructive analysis provides detailed insight into the internal structure of the tablet, far beyond what traditional techniques can offer.

Pharmaceutical Applications

Pharmaceutical researchers and manufacturers use the BELsorp instruments in various stages of product development and quality control. Some examples include:

Formulation Development: Ensuring that excipients and active pharmaceutical ingredients (APIs) blend correctly and result in the desired porosity.
Quality Control: Verifying that tablets produced at scale maintain consistent porosity levels for uniform performance.
Process Optimization: Fine-tuning manufacturing processes like compression and drying to control pore characteristics.

The BELSORP Advantage

What sets the BELSORP series apart from other gas adsorption analyzers is its blend of precision, flexibility, and ease of use. Each model is built with advanced sensors and intuitive software interfaces, allowing for:

High reproducibility and sensitivity: Ideal for pharmaceutical applications that demand strict quality standards.
Flexible measurement modes: From single-point BET surface area analysis to full pore size distribution, BELsorp instruments adapt to your analysis goals.
User-friendly software: The built-in software simplifies operation and data interpretation, making advanced surface science accessible even to less-experienced users.
Wide range of sample types: Whether you're analyzing bulk powders, fine granules, or compressed tablets, BELsorp systems handle diverse sample forms with ease.

Understanding the porosity of pharmaceutical tablets is crucial for developing safe and effective medications. The BELsorp series from Microtrac enables pharmaceutical scientists to explore porosity in greater detail than ever before.

With advanced gas adsorption technology, intuitive software, and high-precision sensors, BELSORP analyzers help turn complex porosity measurements into actionable insights. Their versatility, accuracy, and ease of use make them a cornerstone for pharmaceutical labs focused on formulation development, process optimization, and quality assurance.

Whether you're in early-stage research or managing large-scale production, the BELSORP series provides the confidence and consistency needed to meet modern pharmaceutical standards.

Working together… providing solutions!

As the exclusive Canadian distributor, ATS Scientific Inc. offers localized support for BELSORP instruments. Our factory-trained technical sales team has extensive expertise in scientific instrumentation and analytical methodologies, particularly within the pharmaceutical sector.

ATS provides comprehensive support that includes:

In-depth consultations to match your lab's needs with the right BELsorp model
On-site installation and personalized training
Ongoing technical support and troubleshooting from knowledgeable local staff

Thanks to ATS Scientific's product expertise and commitment to customer care, Canadian users of the BELSORP series benefit from more than just advanced instrumentation, they gain access to a comprehensive support network that ensures long-term success and confidence in their analysis.