According to recent estimates, the worldwide pharmaceuticals market is pegged at $300 billion (USD) per annum and growing. However, in spite of this exponential growth, there are several pharmaceutical products that never reach the clinical trial stage. This can be attributed to the rigorous regulatory measures that have been established to find out the efficacy and safety of a product.
Different components are present in pharmaceuticals, it is critical to ensure that only high-quality formulant and active ingredients are used. Talc is one formulant that is often utilized in pharmaceuticals. This mineral can come in different forms of grades and therefore, it becomes all the more crucial to establish its behavior, safety, and activity.
Such measures go a long way in making sure that the safety of a pharmaceutical product is not affected in any way. One imperative measurement often used to interpret the performance profile of talc is particle size. However, analysis can only be effectively carried out when reliable instruments are used along with knowledgeable experts.
Talc and its importance within the pharmaceutical industry
Hydrated magnesium silicate present in talc is obtained through the metamorphism of magnesian minerals in the presence of water and carbon dioxide gas (Mondo Minerals, 2015). In many industrial applications, talc has been shown to be highly effective and offers five exclusive properties such as whiteness, affinity for organic chemicals, softness, lamellarity, and chemical inertness. This substance is highly unique and is utilized in both domestic and industrial applications (Eurotalc, 2015).
The pharmaceutical industry is the major area where talc is primarily used for its diversity. Since this mineral meets all the criteria of a diluent and glidant, it is extensively utilized as a pharmaceutical formulation and processing aid. For instance, it is used as a lubricant and anti-caking agent in tablet making, a filler and an excipient for pills, and even as a dissolution retardant for making controlled-release products. Talc is also utilized as a new powder coating in the production of extended-release pellets (Jadhav et al., 2013).
The challenges of utilizing talc within pharmaceuticals
Regardless of the extensive applications of talc in the pharmaceutical sector, production processes still continue to present a major problem. Regulated and stringent measures and standards have been put in place for guaranteeing lot to lot consistency, which in turn ensures the quality of products and delivers the same clinical profile, which is the most important aspect.
Proper planning is required to build quality into the product, so that any possible failures can be suitably prevented. Quality should be built into the product from the beginning, basic analysis of the end product is not going to work (Kumar, 2015).
The supply of pharmaceutical product constituents, including talc, is outsourced by pharmaceutical firms so as to subject them to rigorous quality control and tests. Such meticulous quality control measures for pharmaceuticals are undertaken to obtain pharmaceutical-grade constituent components.
Although pharmaceutical companies themselves are responsible for ensuring the quality of their end products, component suppliers dealing in formulated pharmaceutical products should also subject their products to rigorous tests and quality control so that they deliver high-quality products that meet all the required specifications.
Addressing stringent quality control challenges within the pharmaceutical industry
Measurement of particle size is one way to deal with the issues related to the quality control of pharmaceuticals as well as the application of talc. This process makes it possible to evaluate the material's behavior and activity and also affects the properties of material like suspension stability, reactivity, efficacy of delivery, dissolution rates, texture, appearance and feel, packing density, rheology, porosity and handling.
Additionally, talc producers can use particle characterization methods to offer an A grade range of talcs that include performance-designed, quality-controlled features to fulfill the complex process needs of the pharmaceutical manufacturing sector.
A wide range of methods can be used to find out the products’ particle size, but the selected sizing technique will rely on the size distribution characteristics and the nature of the sample that are of major significance.
There is no suitable method for all applications or materials, and effective techniques comprise air permeability, dynamic light scattering, static light scattering, electrical sensing zone, dynamic image analysis, and X-ray sedimentation. However, the availability of many different methods along with many numbers of vendors makes it a challenging prospect to choose a suitable but consistent system for quality control.
Multiple techniques to obtain a complete particle size
A technique that is extensively used for particle size analysis is X-ray sedimentation but in order to find out the size distribution versus quantity of various particulates in an effective way, additional measurement methods would need to be applied. Within the scope of particle size analysis, there are many number of additional measurement methods.
For instance, the static light scattering technique helps in establishing the particle size from the way the particles scatter light. Low angle light scattering is considered to be the standard application of static light scattering, wherein a source of monochromatic, coherent light illuminates a group of particles, thus making it easy to determine their size from the relative intensity of the dispersed light with regard to the scattering angle.
Another popular particle size method for macro molecules and submicron particles is dynamic light scattering in which Stokes-Einstein equation is used to determine the hydrodynamic size from the quantified diffusion coefficient of the particles in suspension.
In the air permeability method, the principle of pressure drop occurring throughout a packed powder bed is used, and by changing the height of the sample, an average aerodynamic particle size, and aerodynamic surface area can be established as a function of flow rate and pressure drop according to the Kozeny-Carman equation.
Electrical sensing zone, also known as the Coulter principle, is yet another method that examines samples in a particle by particle fashion. A major benefit of this technique is that only a small amount of sample is required for analysis yet the highest resolution of particle size measurement of other methods can be obtained.
Lastly, in dynamic image analysis, particles are first homogenously suspended in a carrier liquid and then allowed to pass via a thin flow cell in the optical path. This is followed by transmitting light via the flow cell so that silhouettes of the particles are projected onto a camera of high resolution. Thanks to the high-resolution camera, high frame rate, and a high-speed host PC, a count of particles can be easily defined each second in real-time.
Application of Micromeritics principles
With the availability of various measurement options, it becomes imperative to account for the pros and cons of each measurement option so that the right method is used. Users can avail the help of a service provider who provides a wide range of particle size analyzers along with knowledgeable expertise so that they can be properly informed and thus get the right kind of advice on which method to use.
Lab Manager recently carried out a survey, in which 10 features were emphasized as most significant while buying a particle size analyzer. As high as 83% of respondents looked for superior repeatability (Henderson, 2015), an aspect fully agreed upon by David Brenton, who is an industry expert and IMERYS’ Quality Control Laboratory Manager. This was the reason why Micromeritics was selected as a specialist partner by IMERYS more than 15 years ago.
Brenton said that without dependable instruments, IMERYS would not have been able to function properly, but through its specialist partner, the company realized that precision, accuracy, and reliability would be unrivaled, and therefore has complete faith in the reliability of the results obtained.
Given the complex nature of particle sizing, another issue faced by talc producers is to gain access to technical experts, who could help them understand the obtained results. In Lab Manager’s survey, 44% of respondents looked for vendors that provide support for their research-related needs (Henderson, 2015).
A vendor that has informed experts or scientists can additionally assist particle size measurements, thus any questions or challenges related to research are addressed, and the highest quality product is also achieved. David Brenton was considerably happy with Micromeritics’ Sedigraph®, which has been specifically designed for X-ray sedimentation and also with its technical expertise.
Brenton added that his specialist partner employs professionals who have extensive knowledge about the particle size field and the associated instruments. which means that if there is a research challenge, IMERYS can be rest assured that it will have the required support and help to resolve it.
In one instance, IMERYS was asked to carry out particle size analysis under set-up conditions that had never before been used by the company. The partner’s staff was experienced enough to provide the optimum method for preparing and testing the material, and even provided a scenario of options.
Without Micromeritics’ help, the material would not have been tested in an effective way. With customized solutions available, IMERYS considers its specialist partner and its employees as a vital part of its quality control team.
Likewise, Dr. Mario Mondonico, R&D at IMI Fabi S.p.A, also enlisted the help of Micromeritics to effectively execute quality controls on talc powders. Similar to many other companies, he wanted to team up with a vendor who can provide reliable instruments as well as tailored solutions from experienced staff.
According to Dr. Mondonico, Fabi S.p.A shares an open relationship with Micromeritics, and the technical expertise provided by its application scientists has considerably improved the research many times. In one certain situation, Dr. Mondonico and his colleagues required assistance to find out the particles’ hydrophilicity and hydrophobicity.
On contacting its strategic partner, a teleconference was arranged with a particle size expert that made it possible to obtain positive results rapidly and accurately, Dr. Mondonico added.
Within the scope of the talc production field, it is very important to acquire a detailed overview of the material’s profile so that only the highest quality product is marketed. Quality control is also very important within the pharmaceutical sector to ensure that the same clinical profile is delivered lot after lot, with the highest quality products. It is imperative to have such stringent regulatory and quality controls in this field because problems in pharmaceutical manufacturing can lead to serious consequences.
By collaborating with a vendor who provides dependable and high-quality instruments along with well-informed professionals, customers can benefit from personalized solutions that are fully customized to meet their specific applications needs. This can help in realizing high-quality talc and other materials, which can then be confidently used in pharmaceuticals and other highly regulated areas.
Produced from materials originally authored by Greg Thiele, General Manager, Micromeritics Instrument Corporation.
- Mondo Minerals. (2015). The Softest Mineral in the World: Mineralogy and Geology. Available: http://www.mondominerals.com/en/talc-production/mineralogy-geology/. Last accessed 4 Jan 2016.
- Eurotalc. (2015). Functions and applications of talc. Available: http://www.eurotalc.eu/functionsapplication.html. Last accessed 4 Jan 2016.
- Jadhav, N.R. Paradkar, A.R. Salunkhe, N.H. Karade, R.S. Mane, G.G. (2013). Talc: A versatile pharmaceutical excipient. World Journal of Pharmacy and Pharmaceutical Sciences. 2 (6): 4639-4660.
- Kumar, G.P. (2015). Quality control issues in the pharmaceutical industry.
- Henderson T. (2015). Are You in the Market for a ... Particle Size Analzyer? Available: http://www.labmanager.com/surveys/2015/09/are-you-in-the-market-for-a-partice-size-analyzer-#.VnFXOmdFBjo. Last accessed 16th Dec 2015.
About Micromeritics Instrument Corporation
In the early 1960’s, a graduate student at the Georgia Institute of Technology named Warren Hendrix and his advisor, Dr. Clyde Orr, built what is believed to be the first all-metal, transportable gas adsorption analyzer.
Their vision was to provide a commercially available instrument that would allow anybody (with just a small amount of training) to measure the surface area of materials and particulates using gas adsorption methodology.
The two first realized the need for such an instrument two years earlier while working on a research project involving measuring the surface area of particles using glass rack technology (a slow and tedious process requiring constant monitoring).
They understood that with better-designed equipment, they could simplify the complexities of particle analysis and convey the benefits of this science to industry.
The term "micromeritics" is used to describe the science and technology of small particles. It was the the obvious choice for the name of the Micromeritics Instrument Corporation, founded by Warren Hendrix and Clyde Orr in July of 1962.
Micromeritics was the first company to market commercially automated surface area, mercury penetration, and sedimentation particle size analyzers. Micromeritics is world-renowned for its pioneering innovations in these areas and others, including porosimetry, density, zeta potential, and chemisorption analysis.
The company has also led the way in the areas of liquid chromatography, density, automatic sample delivery, TPD/TPR chemisorption, balanced adsorption surface area, and DFT Plus® (NLDFT) data interpretation.
The company has been granted over forty patents in these combined areas of materials characterization. Micromeritics' corporate headquarters, manufacturing, R&D, and the Materials Analysis Laboratory are all located in Norcross (Atlanta), Georgia, USA.
They have direct sales and service offices, as well as a full network of distributors, throughout the world. Micromeritics is an ISO 9001 : 2008 company and a recipient of the prestigious "E" Award for excellence in exports, awarded in 1990 by President George H.W. Bush.