Dr Ramachandran’s first degree and masters were in Physics and her MPhil was in Theoretical Physics calculating the force constants of inorganic systems using the Infra-red and Raman spectroscopic studies. She carried out her PhD in experimental Physics where she investigated near and inner surface characteristics and defects of materials using luminescence (thermoluminescence, radioluminescence and cathodoluminescence) techniques. She has also worked as a voluntary researcher in the areas of Liquid crystal simulation at the University of Lancaster and in Astro Physics at the Liverpool John Moores University. With strong research experience in molecular modelling, and crystallisation with teaching experience in pharmaceutical product formulation, Vasuki is passionate about promoting digital design for the development and manufacturing of quality pharmaceutical products.
Dr. Ramachandran’s research interests include the following:
The external shape of a crystal influences particle properties and in turn affects the processing. The crystal shape is greatly influenced by the impurity and/or crystal growth environment. Qualitative and quantitative understanding of the intrinsic and extrinsic synthons (intermolecular interactions) is fundamental to the digital design of drug products and/formulation. Vasuki’s interests lie in applying molecular modelling approaches as complementary screening tools to understand the interparticle interactions that are fundamental to active pharmaceutical ingredient (API)/excipient compatibility, effect of solvent on the crystal morphology, particle agglomeration, and nucleation. The feasibility test that she carried out at the diamond synchrotron light source to simultaneously characterise the molecular orientation by X-ray diffraction and particle shape by X-ray tomography of micron-sized particles led to the development of a methodology via a PhD project to get a complete description of a particle’s 2-dimensional and 3-dimensional shape. The characterization method coupled with molecular modelling will give a unique understanding to why particles behave in characteristic ways especially in pharmaceutical secondary processes such as size reduction, granulation, blending and agglomeration/de-agglomeration processes.
Cathodoluminescence (CL) is a well-established characteristaion technique widely used in minerology, materials science and geochemistry but seldom used in pharmaceutical industry. When a sample is irradiated with high energy electrons, the delocalsied electrons will be excited which when reverting back to the ground state, release the excess energy as light. The light/luminescence is characteristic of the chemical structure, purity and the point defects of the sample. CL has not been used widely to characterize organic materials. Dr. Ramachandran is very keen to exploit this technique combined with synthonic engineering approaches to investigate the surface and near-surface characteristics of pharmaceutical materials.
Some of Dr. Ramachandran’s key publications include:
- Ramachandran, , Murnane, D., Hammond, R.B., Pickering, J., Roberts, K.J., Soufian, M., Formes, B., Jaffari, S., Martin, G., Collins, E., Pencheva, K. ‘Formulation Pre-Screening of Inhalation Powders Using Computational Atom-Atom Systematic Search Method’ Molecular Pharmaceutics 12 (2015) 18-33
- Merrifield, D.R., Ramachandran, V., Roberts, K.J., Armour, W., Axford, D., Basham, M., Connelly, T., Evans, G., McAuley, K., Owen, R., Sandy, J. A novel technique combining high resolution synchrotron X-ray micro-tomography and X-ray diffraction for characterization of microparticulates Measurement Science & Technology 22 (2011) (12pp)
- Hammond R.B., Ramachandran V., Roberts K.J. Molecular Modelling of the Incorporation of Habit modifying additives: α-glycine in the presence of l-alanine’ CrystEngComm 13 (2011) 4935
- Hammond, R.B., Pencheva, K., Ramachandran, V. and Roberts K.J., Application of Grid-Based Molecular Methods for Modeling Solvent-Dependent Crystal Growth Morphology: Aspirin Crystallized from Aqueous Ethanolic Solution. Cryst. Growth & Design, 7 (2007) 1571-1574.
- Ramachandran, V., Maghrabi, M., Xiqi Feng, Townsend, P.D., Luminescence Spectra of doped and undoped Lead Tungstate crystals, Radiation Effects & Defects in Solids, 157 (2002) 609 –613.
- Kurt, K., Ramachandran, V., Mughrabi, M., Townsend, P.D. and Yang, B., Influence of phase transitions of ice on near surface cathodoluminescence, Physics, C: Condens. Matter, 14 (2002) 4319 – 4328.
- Mohan, S., Gunasekaran, S., Vasuki G. Dynamical model of force constants on the vibrational analysis of isothiocyanate and silyl isocyanate molecules, Indian Journal of Physics, B 62B (1988) 175-180
- Mohan, S., Vasuki G., Srinivasan, S. Laser Raman spectrum of α-bromotoluene, of the Indian National Science Academy, Part A., 53 (1987) 646-649
- Roberts, K.J., Hammond, R. B., Ramachandran, V., Docherty, R. ‘Synthonic Engineering: From Molecular and Crystallographic Structure to the Rational Design of Pharmaceutical Solid Dosage Forms’, in Computational Approaches in Pharmaceutical Solid State Chemistry, Ed: Abramov, Y.A. ISBN 9781118700747, Wiley.