Dhamoon et al. DOI: 10.5138/09750215.2204 International Journal of Drug Delivery 2018;10(1):01-11 ORIGINAL RESEARCH ARTICLE Particle Size Characterization- Techniques, Factors and Quality-by-design Approach Rupinder Kaur Dhamoon 1 , Harvinder Popli 1 , Geeta Aggarwal 1 , Madhu Gupta 1 * Introduction Particle size and size characterization knowledge act as a prereq- uisite for all the processes which are involved in the production of a formulation. They influence mechanical strength, electri- cal and thermal properties of the finished product. Massive pro- duction losses can occur if particle sizes of the materials being used in the process are not appropriately monitored [1]. A wide range of materials starting from proteins and polymers, micro- emulsions, viruses, droplets, pigments up to sand and cement re- quire particle characterization [2]. Particle size characterization Correspondence: madhugupta98@gmail.com 1 Delhi Pharmaceutical Sciences Research University, Pushpvihar, Sector-3, M.B Road,, New Delhi, 110017, India Full list of author information is available at the end of the article. Received: 28 Oct 2017, Accepted: 09 Jan 2018 is about describing particle sizes in a formulation that helps in understanding, predicting and optimizing pharmacokinetic prop- erties of that formulation. Accurate determination of particle size is necessary for pharmaceutical industry. It is a physical param- eter that must be specified, examined and managed right from the starting material to the finished product. Despite the modern instrumentation, there are some challenges faced in the field of particle size characterization- Need for an appropriate method development specific to drug type, form, and delivery. The very minute quantity of sample available, especially, in initial stages of drug development. Inaccuracies in data interpretation due to most of the particles being non-spherical in shape. Abstract Particle size characterization is one of the key areas involved in quality assurance. The concept of particle size and size char- acterization acts as a foundation for all the processes involved in the production of a formulation; from manufacturing to quality control operations. Particle size characterization dictates many properties of the finished product. Particle size characterization of samples is important to make a better quality product, improve its appearance, taste, texture and shelf-life. There are many instruments for particle size characterization that are available commercially. Each instrument is based on a different technique and each technique is based on a different principle. Selecting the right particle size characterization technique for the given sample is a challenging decision. The choice of technique is made according to the sample. Sometimes even a combination of techniques is used to obtain accurate results. There are several factors upon which choice of technique depends like size range, sample quantity, cost-effectiveness etc. To ensure appropriate quality standards in the field of particle sizing and particle size characterization, ICH and US-FDA have recently insisted on including Quality-by-design approach in the pharmaceutical indus- try. Application of QBD approach to particle size characterization techniques ensures a resilient method which gives reproducible results. It aids in reducing result and method variations and promotes productivity and quality. The main objectives of this review are first, to understand the principle, instrumentation, and working of commercially used techniques and to compare their pros and cons; secondly, to study the factors which govern the choice of technique and lastly, to understand the concept of Quality by design and its role in particle size characterization through some example. Keywords: Particle size characterization; techniques; factors; QBD 1 brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by Advanced Research Journals