Changquan Calvin Sun Lab

Pharmaceutical Materials Science and Engineering Laboratory

Department of Pharmaceutics
College of Pharmacy, University of Minnesota

Our research focuses on manufacturing science of solid dosage forms, such as tablets and capsules. Formulation and process development is achieved by a clear scientific understanding of powders, including their flow and compaction properties. In this way, design replaces trial and error, and improved quality results.

We rely on three levels of control to attain the desired powder properties for successful manufacturing: (1) study and specification of the physico-mechanical properties of drugs; (2) incorporation of appropriate excipients for optimum mechanical properties; and (3) optimization of processes such as mixing, granulation, and compaction, based on a mechanistic understanding.


Dr. Changquan Calvin Sun – Lab Supervisor,

Arushi Agarwal – MS Student (Sept. 2021-Present)
Vedant Bhagali – MS Student (Sept. 2021-Present)
Dr. Ramy Elsergany – Postdoctoral Associate (Feb. 2022-Present)
Dr. Chamara Gunawardana – Postdoctoral Associate (Nov. 2020-Present)
Dr. Yiwang Guo – Postdoctoral Associate (Jan. 2016-Present)
Pin-Syuan Huang – MS Student (Sept. 2022-Present)
Vikram Joshi – PhD Student (Sept. 2021-Present)
Dhaval Mori – PhD Student (Sept. 2022-Present)
Gerrit Vreeman – PhD Student (Sept. 2018-Present)
Zjian Wang – PhD Student (Sept. 2021-Present)
Tianyi Xiang – MS Student (Sept. 2021-Present)
Yunping Zhoujin – PhD Student (Sept. 2022-Present)

Past Members

Dr. Shao-Yu Chang – PhD Student (Sept. 2012-May 2019)
Dr. Sayantan Chattoraj – PhD Student (Sept. 2008-Nov. 2012)
Dr. Hongbo Chen – PhD Student (Sept. 2015-July 2020)
Prof. Jiamei Chen – Visiting Scholar (Dec. 2015-Dec. 2016)
Joan Cheng – PhD Student (Sept. 2019-March 2022)
Dr. Miles Chen – Assistant Scientist (Apr. 2010-Dec. 2010)
Dr. Jiangnan Dun – PhD Student (Sept. 2014-Feb. 2020)
Dr. Xingchu Gong – Visiting Scholar (Dec. 2013-Dec. 2014)
Prof. Xin He – Visiting Scholar (Feb. 2015-Feb. 2016)
Dr. Cosima Hirschberg – Visiting Scholar (May 2018-Sept. 2018)
Shenye Hu – PhD Student (Sept. 2014-Sept. 2022)
Dr. Xiang Kou – Postdoctoral Fellow (Aug. 2011-Nov. 2012)
Zhengxuan Liang – MS Student (Sept. 2018-Sept. 2020)
Dr. Lili Liu – Visiting Scholar (Aug. 2015-Sept. 2016)
Sibo Liu – MS Student (Sept. 2017-July 2019)
Prof. Shuyu Liu – Visiting Scholar (Feb. 2016-Jan. 2017)
Dr. Benyong Lou – Visiting Scholar (Oct. 2013-Oct. 2014)
Dr. Manish Mishra – Postdoctoral Associate (Aug. 2018-June 2021)
Dr. Frederick Osei-Yeboah – PhD Student (Sept. 2010-Sept. 2015)
Dr. Sarsvat Patel – Postdoctoral Fellow (Apr. 2010-Aug. 2012)
Dr. Shubhajit Paul – Postdoctoral Fellow (Jan. 2014-Mar. 2019)
Dr. Reddy Perumalla – Research Associate (Apr. 2010-Dec. 2015)
Dr. Limin Shi – Research Associate (Feb. 2009-Oct. 2014)
Zhongyang Shi – MS Student (Sept. 2017-July 2019)
Byoung-Hwa Son – Visiting Scientist (June 2010-June 2011)
Amy H. Sun – Lab Manager (June 2016-Dec. 2016)
Dr. Wei-Jhe Sun – PhD Student (Sept. 2012-Dec. 2017)
Dr. Majeed Ullah – Visiting PhD Student (Jan. 2014-July 2014)
Dr. Chenguang Wang – Visiting Scholar (June 2013-Sept. 2013, Dec. 2014-Oct. 2015), Researcher (June 2016-Nov. 2021)
Dr. Kunlin Wang – PhD Student (Sept. 2015-Sept. 2020)
Prof. Mingjun Wang – Visiting Scholar (Mar. 2016-Mar. 2017)
Shan Wang – Visiting Scholar (Nov. 2019-May 2020)
Prof. Wenxi Wang – Visiting Scholar (Mar. 2016-Mar. 2017)
Prof. Jun Wen – Visiting Scientist (May 2019-June 2020)
Dr. Hiroyuki Yamashita – Research Scholar (Dec. 2015-Nov. 2016)
Hao Ye – Visiting Scientist (Aug. 2011-Nov. 2011)
Liang Zhengxuan – Visiting Scholar (Jan. 2018-June 2018)
Prof. Qun Zhou – Visiting Associate Research Professor (May 2011-May 2012)
Ling Zhu – MS Student (Sept. 2016-July 2019)


Compaction simulators (Presster & Styl'One)

  • Collecting fundamental physical parameters during tableting
  • Material sparing (1 – 5 g of powder)
  • Vast amount of information available, e.g., ejection force, take-off force, radial die-wall stress, compaction pressure-time profile, volume-time profile, tensile strength – pressure profile
  • Variable tableting speeds (capable of simulating most commercial tablet presses and roller compactors)
  • Flexible with tablet size and shape
  • Reliable prediction of success or failure during scale up

Ring shear cell

  • A well-established methodology
  • Predictive of powder flow property during powder transfer processes
  • Flow function, cohesion, and internal friction angle, bulk density
  • Superior to any other methods that assess flow property based on single point measurement     
  • A large in-house flow database is available

Zwick universal material testing machine

  • A wide range of force (0.1 – 200 kN)
  • User-friendly software enabling study of relaxation and creep behavior
  • Controlled by force or displacement
  • Variable speed (0.01 - 100 mm/s)

Texture analyzer

  • High sensitivity (8 mN – 500 N)
  • Suitable for micro-indentation, film adhesion, mechanical properties of film, tablet tensile strength, breaking strength of granules


  • Suitable for studying mechanical properties of single crystals, films, and other small specimen
  • Exceptional sensitivity and spatial resolution

Roller compactor (Alexanderwerk, WP120)

  • Fully instrumented (feed screw speed, roll pressure, roll gap, milling speed, vacuum)
  • Micro batch (5-10g batch size)

Other Instruments

Powder characterization

  • Helium pycnometer
  • Atomic force microscope (AFM)
  • Particle size analyzer
  • Scanning electron microscope (SEM)
  • Environmental SEM
  • X-Ray micro-tomography (micro-CT)
  • Zygo optical profilometer/Tencor stylus profilometer
  • Gas sorptometer (ASAP 2000)
  • Contact Angle Goniometer
  • Geopyc (envelop density measurement)

Solid-state characterization

  • X-ray diffractometry (powder and single crystal) with temperature control
  • Moisture sorption apparatus
  • Thermo-gravimetry analyzer (TGA)
  • Differential scanning calorimeter (DSC)
  • Thermal mechanical analyzer (TMA)
  • Transmission electron microscope (TEM)
  • X-ray Photoelectron Spectroscopy (XPS)
  • Rotating disc dissolution rate apparatus (RDDR)
  • FTIR and Raman spectroscopy
  • Nanoindenter (Hysitron TI-980)

Processing equipment

  • Lab scale spray-drier
  • Crystallizer (1 liter)
  • Lab-scale micronizer (Jet-mill)
  • PK blender
  • High shear granulator (1L, custom made; RotoLab, 1.8L)
  • Turbula mixer (Model T2F)
  • Comil (Model U5, underdriven)


  • Materials Studio & Cambridge Crystal Database (supported by Minnesota Supercomputing Institute)

Collaboration Opportunities

We welcome opportunities to collaborate with industry on challenging projects.  Some examples of such collaboration are listed below.

  1. Assessing manufacturability of a formulation
    1. Powder flow
    2. Powder tabletability
    3. Hygroscopicity
    4. Drug release profile
    5. Sticking tendency
  2. Profiling solid-state properties of drugs and excipients
    1. Polymorph screening and characterization
    2. Salt screening
    3. Cocrystal screening
    4. Crystallinity
    5. Crystal structure elucidation
    6. Thermodynamic stability relationship
    7. Process-induced crystal form conversion (trouble-shooting and control)
    8. Drug-excipient compatibility
  3. Profiling mechanical properties (crystal and powder)
    1. Yield strength (in-die and out-of-die Heckel analysis)
    2. Young’s modulus and tensile strength
    3. Indentation hardness (nano- or micro-)
    4. True density
    5. Porosity of irregular specimens
    6. Understanding tabletability, compressibility, compactibility, and elastic recovery, etc., under realistic manufacturing conditions
    7. Mechanical behavior under high (GPa) pressures
  4. Powder engineering (feasibility tests)
    1. Formulation development
    2. Process understanding (direct compression, dry and wet granulation)
    3. Surface engineering for enhanced pharmaceutical properties
  5. Instrument sharing
    1. Easy access to state-of-the-art instruments
    2. Cost savings on instrument maintenance and human resources
    3. Ready access to expert guidance and training
    4. Rapid turnaround time
    5. High quality data