[learn_more caption=”Zhibing Zhang”]

Professor Zhibing Zhang (ZZ) obtained his BSc in Chemical Engineering from Hefei University of Technology, China in 1982, MSc and PhD in Chemical Engineering from East China University of Science and Technology, Shanghai in 1985 and 1988 respectively, and moved to Birmingham, UK in 1989. Over the last 25 years, he has built up an international reputation for developing a novel micromanipulation technique to mechanically characterize single micro/nano particles for various academic and industrial applications, and for his novel research in encapsulation of different active ingredients for pharmaceutical, nutraceutical, human care and fabric care applications.

ZZ is a member of the Editorial Boards of Journal of Microencapsulation, Artificial Cells, Nanomedicine and Biotechnology and Journal of Engineering, Editor of Chemical Engineering of Cogent Engineering, UK representative to the Management Committee of European COST 840 on Bioencapsulation Innovation and Technologies, Member of Consumers and Diversified Committee of Controlled Release Society, EPSRC Peer Review College and Overseas Assessor of Chinese Academy of Sciences. His research has resulted in 120 academic journal papers, and 200 other publications including book chapters, conference papers, patents and a number of invited presentations at international conferences or meetings. His work on developing “perfume microcapsules for detergents” in collaboration with Proctor & Gamble Belgium was highly commended for the Global Innovative Product Award 2014 by the Institution of Chemical Engineers, UK (https://www.youtube.com/watch?v=SltXHwGDMqA).

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School of Chemical Engineering,
University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
Email: z.zhang@bham.ac.uk

 

Compaction of active ingredients such as probiotic cells with excipients into rigid tablets is challenging since the former are suceptible to high compression pressure. In order to produce rigid tablets at low compression pressure, it is important to understand the mechanical properties of the primary particles such as viscoelasticity and plasticity, and how the mechanical properties affect their compressibility. However, it was not possible to measure the mechanical properties of single micro-particles (~1 mm) directly until a novel micromanipulation technique has been developed at Birmingham. This technique is based on compression of single micro-particles between two flat surfaces and simultaneous measurement of the force applied to them as a function of displacement. Valuable mechanical properties can be obtained directly from such measurements, including the force required to cause a given nominal deformation of the micro-particles, their size, visco-elastic-plastic behaviour, rupture force and nominal deformation at rupture. Mathematical modelling of the force versus deformation data based on appropriate constitutive equations of the materials can be used to determine their intrinsic material properties, such as Young’s modulus, yield stress, stress and strain at rupture. The mechanical properties of different primary particles including yeast cell granuls, polymer particles and agglomerates have been determined by the micromanipulation technique. The mixture of these primary particles were also compacted in cylindrical dies to tablets. The bulk compression data of the particles were analysed using differnet models, which have been related to the mechanical properties of the primary particles. The details of these studies and their applications in producing probiotic tablets will be presented.