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.

People

Dr. Changquan Calvin Sun – Lab Supervisor, sunx0053@umn.edu

Mr. Hongbo Chen  PhD Student (Sept. 2015-Present), chen4515@umn.edu
Ms. Joan Cheng  PhD Student (Sept. 2019-Present), cheng842@umn.edu
Mr. Jiangnan Dun  PhD Student (Sept. 2014-Present), dunxx004@umn.edu
Ms. Yiwang Guo  PhD Student (Jan. 2016-Present), guoxx836@umn.edu
Ms. Shenye Hu  PhD Student (Sept. 2014-Present), huxxx839@umn.edu
Ms. Zhengxuan Liang  MS Student (Sept. 2018-Present), liang650@umn.edu
Dr. Manish Mishra  Post-Doctoral Associate (August 2018-Present), mmishra@umn.edu
Mr. Gerrit Vreeman  PhD Student (Sept. 2018-Present), vreem012@umn.edu
Dr. Chenguang Wang  Post-Doctoral Associate (June 2016-Present), wang4889@umn.edu
Ms. Kunlin Wang – PhD Student (Sept. 2015-Present), wang3248@umn.edu
Mr. Shan Wang  Visiting Scholar (Nov. 2019-Present), wang9664@umn.edu
Prof. Jun Wen  Visiting Scientist (May 2019-Present), wen00065@umn.edu

Past Members

Dr. Shao-Yu Chang  PhD Student (Sept. 2012-May 2019)
Dr. Sayantan Chattoraj – PhD Student (Sept. 2008-Nov. 2012)
Prof. Jiamei Chen  Visiting Scholar (Dec. 2015-Dec. 2016)
Dr. Miles Chen  Assistant Scientist (Apr. 2010-Dec. 2010)
Dr. Xingchu Gong  Visiting Scholar (Dec. 2013-Dec. 2014)
Prof. Xin He  Visiting Scholar (Feb. 2015-Feb. 2016)
Ms. Cosima Hirschberg  Visiting Scholar (May 2018-Sept. 2018)
Dr. Xiang Kou  Post-Doctoral Fellow (Aug. 2011-Nov. 2012)
Ms. Lili Liu  Visiting Scholar (Aug. 2015-Sept. 2016)
Mr. 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. Frederick Osei-Yeboah  PhD Student (Sept. 2010-Sept. 2015)
Dr. Sarsvat Patel  Post-Doctoral Fellow (Apr. 2010-Aug. 2012)
Dr. Shubhajit Paul  Post-Doctoral Fellow (Jan. 2014-Mar. 2019)
Dr. Reddy Perumalla  Research Associate (Apr. 2010-Dec. 2015)
Dr. Limin Shi  Research Associate (Feb. 2009-Oct. 2014)
Mr. Zhongyang Shi  MS Student (Sept. 2017-July 2019)
Mr. Byoung-Hwa Son  Visiting Scientist (June 2010-June 2011)
Dr. Wei-Jhe Sun  PhD Student (Sept. 2012-Dec. 2017)
Mr. Majeed Ullah  Visiting PhD Student (Jan. 2014-July 2014)
Mr. Chenguang Wang  Visiting Scholar (June 2013-Sept. 2013, Dec. 2014-Oct. 2015)
Prof. Mingjun Wang  Visiting Scholar (Mar. 2016-Mar. 2017)
Prof. Wenxi Wang  Visiting Scholar (Mar. 2016-Mar. 2017)
Dr. Hiroyuki Yamashita  Research Scholar (Dec. 2015-Nov. 2016)
Ms. Hao Ye  Visiting Scientist (Aug. 2011-Nov. 2011)
Ms. Liang Zhengxuan  Visiting Scholar (Jan. 2018-June 2018)
Prof. Qun Zhou  Visiting Assoc. Research Professor (May 2011-May 2012)
Mr. Ling Zhu  MS Student (Sept. 2016-July 2019)

Instrumentation

Compaction simulator (the only unit in a pharmacy school in the U.S.)

  • 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

Nano-indenter

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

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

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

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)

Modeling

  • 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

a. Powder flow
b. Powder tabletability
c. Hygroscopicity
d. Drug release profile
e. Sticking tendency

2. Profiling solid-state properties of drugs and excipients

a. Polymorph screening and characterization
b. Salt screening
c. Cocrystal screening
d. Crystallinity
e. Crystal structure elucidation
f. Thermodynamic stability relationship
g. Process-induced crystal form conversion (trouble-shooting and control)
h. Drug-excipient compatibility

3. Profiling mechanical properties (crystal and powder)

a. Yield strength (in-die and out-of-die Heckel analysis)
b. Young’s modulus and tensile strength
c. Indentation hardness (nano- or micro-)
d. True density
e. Porosity of irregular specimens
f. Understanding tabletability, compressibility, compactibility, and elastic recovery, etc., under realistic manufacturing conditions
g. Mechanical behavior under high (GPa) pressures

4. Powder engineering (feasibility tests)

a. Formulation development
b. Process understanding (direct compression, dry and wet granulation)
c. Surface engineering for enhanced pharmaceutical properties

5. Instrument sharing

a. Easy access to state-of-the-art instruments
b. Cost savings on instrument maintenance and human resources
c. Ready access to expert guidance and training
d. Rapid turnaround time
e. High quality data