Dr. Priti Sundar Mohanty
Associate Professor (I), School of Chemical Technology & School of Biotechnology
Ph. D. in Physics (Soft Condensed Matter), Material Science Division, Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, India.
M. Sc. And M. Phil in Physics, Hyderabad Central University (HCU), Hyderabad, India

Email : [email protected]

Research Interests

Soft Condensed Matter, Material Science, Biophysics

We work on the areas of soft condensed matter (where physics meets chemistry meets biology for fundamental research to technological applications). Materials that come under soft condensed matter system are deformable by shear, electric field or magnetic field. The length (~ nm to microns) and the time (~ microsecond to several seconds) scales of structures of these materials are shifted by many orders of magnitude than atomic or molecular scales. Our interests cover broad research areas that vary from fundamental problems in soft matter physics and its implications to complex biological systems. Following are our areas of research interests.

  1. Structural ordering and Phase behavior in different types of model synthetic colloids such as hard spheres, charged colloids, soft and ultra-soft colloids (stimuli-responsive microgels).
  2. Directed self-assembly of colloids under an external electric field / magnetic field: Towards development of novel responsive materials.
  3. Phase behavior in a bacterial suspension.
  4. Interaction of nano-particles with cells and its physical insight into antibacterial activity.
  5. Development of novel of drug-delivery platform using different types of colloids and controlling its release kinetics.     

Our major research tools include controlled synthesis of different types of colloids, scattering methods (light, x-ray and neutron), confocal microscopy, and computer simulation.

Professional Research Experiences after Ph.D:

  • Research Associate in Department of Advance Polymer Chemistry, Kyoto University, Kyoto, JAPAN (August, 2005 to March, 2006).
  • Postdoctoral Research Assistant, Department of Physics, University of Fribourg, SWITZERLAND (June 2006 to August 2007).
  • Alexander von Humboldt Research Fellow, Physical Chemistry II, RWTH University, Aachen, GERMANY (November 2007 to July 2009).
  • Postdoctoral Research Assistant, Adolphe Merkle Institute for Pure and Applied Nanoscience and Fribourg Centre for Nanomaterials, University of Fribourg, SWITZERLAND (August 2009 to September 2010).
  • Researcher, Division of Physical Chemistry, Lund University, SWEDEN (October 2010 to December 2011).
  • Researcher, Division of Physical Chemistry, Lund University, SWEDEN. (June 2012 to May 2014).

Awards and academic Honors:

  • Fellowship award from Swiss National Foundation, Switzerland (2009-2010).
  • Alexander von Humboldt Fellow, Germany (2007-2009).
  • Awarded fellowship from ministry of Education, Science, Sports and Technology of Japan (2006).                                
  • Reviewer of international journals (Langmuir, Journal of Physics Chemistry B, etc).
  • Awarded Junior & Senior Research Fellowship (1999-2005) for carrying out PhD.
  • Awarded National Scholarship in High School Certificate Examination.

Invited and Colloquia Talks:

  • Escaping the squeeze: Soft particles at high effective volume fractions.
    Tata Institute of fundamental research (TIFR), Hyderbad, (February, 2015).
  • Phase transition kinetics in thermo-responsive and field-responsive ultra-soft colloids.
    A cluster of topical meetings on Current Trends in Condensed Matter PhysicsNISER, Bhubaneswar (Freburay, 2015).
  • Soft colloids with tunable interactions: Microgels as models for soft dipolar fluids.
    Physics of complex colloids: Comploid Conference, Ljubljana, Slovenia (May 2013).
  • Phase Transitions in Soft-Repulsive Colloids
    Forschungszentrum Juelich, 52425, Juelich, Germany ( Nov. 2012).
  • Use of 3D laser light scattering and fluorescent confocal laser scanning microscopy to study phase transitions in soft condensed matter: National Laser Symposium (NLS – 20, India) (Jan 2012).
  • Escaping the squeeze: Soft particles at high effective volume fractions.
    Swedish Neutron Scattering Society Meeting 15 (SNSS-15, Sweden), (August 2011).
  • Structural ordering and phase behavior in responsive microgels
    Department of Physics and Oceanography, Memorial University of Newfoundland, St. John's, NL A1B 3X7, Canada (March, 2011).
  • Interacting soft microgel colloids
    Institute of Physics, Bhubaneswar, India (July, 2011).
  • Escaping the squeeze: Soft particles at high effective volume fractions
    Department of Physics, University of Vienna, Vienna, Austria (September, 2011).
  • Colloidal dispersion, Department of Physics, BJB College, Bhubaneswar (February, 2010).
  • Confocal studies of Rhodamin Labeled Soft and Charged Microgels,
    RWTH University of Aachen,Germany (July, 2009).

Book Chapter: (Review)

Dynamical arrest and crystallization in dense microgel suspensions Priti S. Mohanty, Divya Paloli, Jerome Crassous and Peter Schurtenberger in “Hydrogel Micro- and Nanoparticles”  L. A.  Lyon and Michael J. Serpe, Eds. WILEY-VCH (2012). DOI: http://dx.doi.org/10.1002/9783527646425

Selected Recent Publications (* : Correspondence author )

  1. Thiago Colla, Priti S. Mohanty, Sofi Nojd, Erik Bialik, Aaron Riede, Peter Schurtenberger   
    and Christos N. Likos
    Title: “Self-Assembly of Ionic Microgels Driven by an Alternating Electric Field: Theory, Simulations and Experiments”
    Journal :  ACS  Nano, Volume : 12, Page: 4321, Year : 2018
  2. Sofi Nöjd, Peter Holmqvist, Niels Boon, Marc Obiols-Rabasa, Priti S. Mohanty, Ralf Schweins and Peter Schurtenberger
    Title: “Deswelling behavior of ionic microgel particles from low to ultra-high densities”
    Journal :  Soft Matter, Volume : 14, Page:  4150, Year :  2018
  3. Priti S. Mohanty, Sofi  Nöjd, Kitty van Gruijthuijsen , Jer´ ome J. Crassous , Marc Obiols-Rabasa , Ralf Schweins, Anna Stradner  and Peter Schurtenberger,
    Title : “Interpenetration of polymeric microgels at ultrahigh densities”
    Journal :  Scientific Reports (Nature), Volume: 7, Page:1487, Year:  2017
  4. Smith Sagar Satapathy, Prachi Bhol, Aswathy Chakkarambath, Jagdeep Mohanta, Kunal Samantaray, Suresh K. Bhat, Subhendu K. Panda, Priti S. Mohanty* , Satyabrata Si,
    Title: “Thermo-responsive PNIPAM-metal hybrids: An efficient nanocatalyst for the reduction  of 4-nitrophenol”
    Journal :  Applied Surface Science, Volume: 420, Page: 753, Year: 2017.
  5. K. Samantaray, P. Bhol, B. Sahoo, S. K. Barik, K. Jathavedan, B.R. Sahu,  M. Suar, S.K. Bhat and Priti S. Mohanty*
    Title: “Template-Free Assembly in Living Bacterial Suspension under an External Electric Field”
    Journal:  ACS Omega, Volume: 2, Page: 1019, Year: 2017
  6. Saswati Ganguly, Priti S. Mohanty, Peter Schurtenberger, Surajit Sengupta and Anand Yethiraj
    Title: Contrasting the dynamics of elastic and non-elastic deformations across an experimental colloidal Martensitic transition.
    Journal:  Soft Matter, Volume: 16, Page: 4689, Year: 2017 (Published as a Front Cover Communication in Royal Society Journal)
  7. Priti S. Mohanty,  S. Nöjd,  M. J. Bergman,  G. Nägele,  S. Arrese-Igor,  A. Alegria,  R. Roa,  Peter Schurtenberger and  J. K. G. Dhont
    Title:Dielectric spectroscopy of ionic microgel suspensions
    Journal:  Soft Matter, Volume: 12, Page: 9705, Year: 2016. (Published as a Back Cover Communication).
  8. Priti S. Mohanty*, Payam Bagheri, Sofi Nöjd, Anand Yethiraj, Peter  Schurtenberger
    Title: “Multiple path-dependent routes for phase transition kinetics in thermo-responsive and field-responsive ultra-soft colloids”
    Journal: Physical Review X, Volume: 5, Page: 011030, Year: 2015.

Research

Soft matter and Biophysics

Selected research works are summarized.

  • Phase behavior in a soft-repulsive colloids:
    (Work carried out at Lund University)
    (Collaborators:  Prof. Peter Schurtenberger and Dr. Emanuela  Zaccarelli )

    We use monodisperse poly(N-isopropylacrylamide) (PNIPAM) microgels as a model system for soft repulsive colloids and study their density dependent structural ordering and phase behaviour using confocal laser scanning microscopy (CLSM). Microgel colloids in the swollen state and interact via a Hertzian potential, evidenced through a quantitative comparison of the pair correlation functions obtained with CLSM and computer simulations. We worked over a broad range of effective volume fractions below and above close packing (fcp). CLSM allows us to identify a fluid–glass and a fluid–crystal transition by looking at the structure and dynamics of the suspensions. The density dependent pair-correlation function exhibit clearly visible anomalies at high volume fraction which we interpret as a structural signature of the glass transition related to the particle softness.


    Part of the  work is published as a front cover communication.

     Ref: Soft Matter 9, 10819 (2013), The Journal of Chemical Physics 140, 094901 (2014).

  • Directed self-assembly of ionic microgels under an external electric field:
    (Work carried out at Lund University)
    (Collaborators: Prof. Peter Schurtenberger and Prof. Anand Yethiraj)


    Schematic image of Ionic microgel.

    Ionic microgels are intriguing soft and deformable colloids with an effective pair potential that crosses over from Yukawa-like at large distances to a much softer repulsive interaction at short distances. Moreover, ionic microgels with their ultra-soft interaction potential and a large amount of confined counterions are very attractive model systems to study field-induced self-assembly and related phase transitions.

    We use an alternating electric field to induce a tunable dipolar contribution, and study the resulting particle self-assembly and phase transitions in situ with confocal laser scanning microscopy. We find significant field-induced structural transitions at low, intermediate and as well at very high effective volume fractions (Phieff). At very lowPhieff we observe a transition from an isotropic to a string fluid at low field strength and at higher field strengths, the chains aggregates into the well-defined body–centred tetragonal (BCT) structures. At intermediate Phieff, we find a field-induced crystal (FCC) to dipolar BCT transition, and a gas–BCT coexistence at a higher electric field strength.  At high Phieff, there is a reversible transition from an amorphous to a dipolar crystalline state, followed by the onset of a gas–(string) solid coexistence. Further at far above close packing, evidence for a field-induced arrested phase separation is found.


    Electric field-induced phase behavior in ionic microgel dispersions. The data points correspond to the experiments carried out at different electric field strength Erms(V/mm) and volume fraction, Φeff. 

    Ref: Soft  Matter  9,9199 (2013)Soft Matter 8, 10819 (2012).
  • Phase transition kinetics in thermo-responsive and field-responsive ultra-soft colloids
    (Work carried out at Lund University)
    (Collaborators: Prof. Peter Schurtenberger and Prof. Anand Yethiraj)

    In spite of the importance of solid-to-solid transformations in many areas of materials science and condensed matter physics and the numerous experimental and theoretical studies, a deep understanding of the micro-structural changes and the underlying kinetic mechanisms is still missing.  In this work, we establish a versatile model system composed of micron-scale soft-repulsive colloids where we not only probe the single-particle kinetics in real space and real time using confocal laser scanning microscopy, but also tune the phase transition in a multiple-parameter space (external alternating electric field and temperature). We discovered that the kinetics of crystal-to-crystal transformations is either diffusive or martensitic depending on the path, and we believe that these two path dependent transitions provide the first real-space, particle-level insights of diffusive and martensitic transformations, respectively, in a single system.


    Ref: Physical Review X (In Press, 2015).

    FCC- to- BCT transition

    BCT- to- BCO transition
  • Phase behaviour in bacterial suspensions
    (work at KIIT)
    (Collaborators:  Prof. M. Suar and Dr. Suresh Bhat) :

    Bacteria can occur in a wide variety of shapes and sizes. Their growth kinetics, cooperative phase behaviour and self-organized pattern vary from bacteria to bacteria. In a natural diverse condition, bacteria often adjust with host environments by adopting sophisticated cooperative behaviour and intricate communication capabilities. Utilizing these capabilities, the colonies develop with complex spatial and temporal patterns in response to adverse growth conditions. However, the origin and significance of such sophisticated cooperative behavior is poorly understood and their physical properties related to signaling process remains an open issue to a large extent. We are currently trying to understand structural ordering and phase behavior in different types of bacterial suspensions related to this issue.


    Microscopy image of a bacterial suspension at high concentration.


    Movie of a bacterial suspension at high concentration.

    Ref: 83rd Annual Meeting of Society of Biological Chemists (India) (Abstract, 2015).

 

Collaborators

  1. Prof. Mrutyunjay Suar (Director), School of Biotechnology, KIIT, India.
  2. Prof. S. Kar, School of Biotechnology, KIIT, India.
  3. Dr. R. Samantaray, School of applied sciences, KIIT, India.
  4. Dr. Suresh Bhat, National Chemical Laboratory, Pune, India.
  5. Prof.  Anand Yethiraj, Department of Physics and Physical Oceanography,Memorial University, St. John's, NL, Canada.
  6. Prof. Peter Schurtenberger, Department of physical chemistry, Lund University, Sweden.

Samir R. Mishra, Research Scientist
Subrat K. Barik, Ph. D student
Ealisha Jha, Master student