Ronald A. Siegel, ScD

Professor Siegel received his ScD degree in Electrical Engineering and Computer Science from the Massachusetts Institute of Technology (MIT) in 1984. From 1984 to 1998 he was on the faculty of the School of Pharmacy at the University of California, San Francisco. He moved to the University of Minnesota in 1998, and was Head of the Department of Pharmaceutics from 1999 to 2009 and 2022 to 2024. He is also on the faculty of the Department of Biomedical Engineering.

• Fellow, CRS, 2010
• CRS/Jorge Heller Journal of Controlled Release Outstanding Paper Award, 2003
• CRS/Ethypharm Best Pharmaceutical Paper Award, 2001
• Fellow, American Association of Pharmaceutical Scientists, 1999
• Fellow, American Institute for Medical and Biological Engineering, 1999
• Controlled Release Society (CRS) Young Investigator Research Award, 1989
• American Association of Pharmaceutical Scientists (AAPS)/Pfizer Young Investigator Grant Award, 1988

• President, Controlled Release Society, 1997-1998
• Editorial Boards: Journal of Controlled Release, AAPS Journal

• Intranasal prodrugs and delivery systems for treatment of epilepsy
• Hydrogels and polymer-drug interactions
• Development of inert biodegradable polymers for implants
• Physical and mathematical modeling of processes governing drug disposition

• Polymer synthesis and characterization
• UV-Vis, NMR, FTIR, DSC, DTA, PXRD
• HPLC
• Mathematical and computational modeling

• Drug delivery
• Mathematical modeling

• Graduate course in controlled drug and gene delivery
• Graduate course modules in physical chemistry/physical pharmacy

• PHM/BMEN 8431: Controlled Drug and Gene Delivery: Materials, Mechanisms, and Models
• PHM 8110: Readings in Pharmaceutics
• PHM 8220: Physical Pharmacy Module I
• PHM 8230: Physical Pharmacy Module II
• PHM 8240: Biopharmaceutics Module

• M.C. Calderer, D. Henao, M.S. Sanchez, R.A. Siegel, and S. Song, “Experiments and finite element simulations pertinent to hydrogel debonding from a solid substrate,” Polymer 335, 129702 (2025) DOI: 10.1016/j.polymer.2025.128702
• K.M.H. Jain, I. Duggal, H.H. Hou, and R.A. Siegel, “Artificial Gut Simulator.  A scheme to predict intestinal and plasma concentration-time profiles of a weekly basic BCS-II drug, dipyridamole,” Eur J Pharm Biopharm, 210, 114688 (2025)  DOI: 10.1016/j.ejpb.2025.114688
• T. Xiang, S. Song, R.A. Siegel, and C.C. Sun, “Efficient development of high drug loaded posaconazole tablets enabled by amorphous solid dispersion,” RSC Pharmaceutics, 2, 178-185 (2025) DOI: 10.1039/D4PM00301B
• S. Song, J. Xu, Z. Chen, C.C. Sun, E.J. Munson, and R.A. Siegel, “Miscibility of amorphous solid dispersions:  rheological and solid-state NMR study,” J Pharm Sci, 114, 119-126 (2025) DOI: 10.1016/j.xphs.2024.05.017
• S. Song, X. Yao, C. Wang, C.C. Sun, and R.A. Siegel, “Delaying the first nucleation event of amorphous solid dispersions above the polymer overlap concentration (c*): PVP and PVPVA in posaconazole,” J Pharm Sci, 114, 98-104 (2025) DOI: 10.1016/j.xphs.2024.04.026
• S. Song, S. Cui, C.C. Sun, T.P. Lodge, and R.A. Siegel, “Crystallization inhibition in molecular liquids by polymers above the critical overlap concentration (c*): Delay of the first nucleation,” J Pharm Sci, 114, 82-85 (2025) DOI: 10.1016/j.xphs.2024.02.011
• K.M.H. Jain, H.H. Hou, and R.A. Siegel, “An artificial gut/absorption simulator: Understanding the impact of absorption on in vitro dissolution, speciation and precipitation of amorphous solid dispersions," Mol Pharm, 21, 1184-1899 (2024). DOI: 10.1021/acs.molpharmaceut.3c01180
• R.A. Siegel, “Notes on the Use of Kirchhoff’s Laws in Pharmacokinetics,” AAPS J, 26, 8 (2024). DOI: 10.1208/s12248-023-00875-6
• A. Sahoo and R.A. Siegel, “Drug-polymer miscibility and the overlap concentration (C*) as measured by rheology: Variation of polymer structure,” Pharm Res 40, 2229-2237 (2023)  DOI: 10.1007/s11095-023-03570-5
• K.M.H. Jain, H.H. Hou, and R.A. Siegel, “An artificial gut/absorption simulator: Simultaneous evaluation of desupersaturation and absorption from ketoconazole supersaturated solutions,” J Pharm Sci, 112, 2217-2222 (2023) DOI: 10.1016/j.xphs.2022.09.017
• K.M.H. Jain and R.A. Siegel, “Predetermination of burst times of elastoplastic osmotic capsules,” J Control Rel, 357, 422-431 (2023) DOI: 10.1016/j.jconrel.2023.03.029
• S. Song, C. Wang, B. Zhang, C.C. Sun, T.P. Lodge, and R.A. Siegel, “A rheological approach for predicting physical stability of amorphous solid dispersions,” J Pharm Sci, 112, 204-212 (2023) DOI: 10.1016/j.xphs.2022.08.028
• K.M.H. Jain, H.H. Hou, and R.A. Siegel. “An artificial gut/absorption simulator: Description, modeling, and validation using caffeine,” AAPS J, 24, 87 (2022) DOI: 10.1208/s12248-022-00721-1
• S. Panja, A. Siehr, A. Sahoo, R.A. Siegel, and W. Shen, "Biodegradable elastomers enabling thermoprocessing below 100 ˚C,"  Biomacromolecules, 23, 163-173 (2022) DOI: 10.1021/acs.biomac.1c01197
• A. Sahoo, R. Suryanarayanan, and R.A. Siegel, “Stabilization of Amorphous Drugs by Polymers: The Role of Overlap Concentration (C*),” Mol Pharm, 17, 4401-4406 (2020). DOI: 10.1021/acs.molpharmaceut.0c00576
• D. Rautiola, J. Updyke, K.M. Nelson, and R.A. Siegel, "Diazepam Prodrug Stabilizes Human Aminopeptidase B During Lyophilization," Mol Pharm, 17, 453-460 (2020). DOI: 10.1021/acs.molpharmaceut.9b00880
• A. Hivechi, S. Bahrami, and R.A. Siegel, “Drug release and biodegradability of electrospun cellulose nanocrystal reinforced polycaprolactone,” Mater Sci Eng C., 94, 929-937 (2019). DOI: 10.1016/j.msec.2018.10.037
• D. Rautiola, P. Maglalang, N. Cheryala, K.M. Nelson, G.I. Georg, J.M. Fine, A.L. Svitak, K.A. Faltisek, L.R. Hanson, U. Mishra, L.D. Coles, J.C. Cloyd, and R.A. Siegel, “Intranasal co-administration of a diazepam prodrug with a converting enzyme results in rapid absorption of diazepam in rats,” J Pharmacol Exp Therapeut, 370, 796-805 (2019). DOI: 10.1124/jpet.118.255943
• A. Siehr, B. Xu, R.A. Siegel, and W. Shen, “Colloidal Stability versus Self-Assembly of Nanoparticles Controlled by Coiled-Coil Protein Interactions,” Soft Matter, 15, 7122-7126 (2019). DOI: 10.1039/C9SM01314H
• A. Kim, H. Lee, C. Jones, S.K. Mujumdar, Y. Gu, and R.A. Siegel, “Swelling, Mechanics, and Thermal/Chemical Stability of Hydrogels Containing Phenylboronic Acid Side Chains,” Gels, 4, 4 (2018). DOI: 10.3390/gels4010004
• D. Rautiola, J.C. Cloyd, and R.A. Siegel, “Conversion of a soluble diazepam prodrug to supersaturated diazepam for rapid intranasal delivery: Kinetics and stability,” J Control Rel, 289,1-9 (2018). DOI: 10.1016/j.jconrel.2018.09.013
• Drug-Device Combinations for Chronic Diseases (S. Lyu and R.A. Siegel, eds.), Wiley (2016).
• M. Kapoor, N. Cheryala, D. Rautiola, G. Georg, J.C. Cloyd, and R.A. Siegel, "Chirally Pure Prodrugs and Their Converting Enzymes Lead to High Supersaturation and Rapid Transcellular Permeation of Benzodiazepines," J Pharm Sci, 105, 2365-2371 (2016). DOI: 10.1016/j.xphs.2016.05.011
• M. Kapoor, J.C. Cloyd, and R.A. Siegel, "A Review of Intranasal Formulations for the Treatment of Seizure Emergencies," J Control Rel, 237, 147-159 (2016). DOI: 10.1016/j.jconrel.2016.07.001
• W. Wang, R.A. Siegel, and C. Wang, "Nanocomposite Polymers with "Slimy" Surfaces that Refresh Following Abrasion," ACS Biomaterials Science & Engineering, 2, 180-187 (2016). DOI: 10.1021/acsbiomaterials.5b00182
• A.R. Kirtane, R.A. Siegel, and J. Panyam, "A Pharmacokinetic Model for Quantifying the Effect of Vascular Permeability on the Choice of Drug Carrier: A Framework for Personalized Nanomedicine," J Pharm Sci, 104, 1174-1186 (2015). DOI: 10.1002/jps.24302. PMID: 25583443
• A.S. Bhalla and R.A. Siegel, "Mechanistic Studies of an Autonomously Pulsing Hydrogel/Enzyme System for Rhythmic Hormone Delivery Journal of Controlled Release," J Control Rel, 196, 261-271 (2014). NIHMS640330. DOI: 10.1016/j.jconrel.2014.10.019. PMC4268432
• M. Kapoor, T. Winter, L. Lis, G.I. Georg, and R.A. Siegel, "Rapid Delivery of Diazepam from Supersaturated Solutions Prepared Using Prodrug-Enzyme Mixtures: Toward Intranasal Treatment of Seizure Emergencies," AAPS J, 16, 577-585 (2014). DOI: 10.1208/s12248-014-9596-5. PMID: 24700272
• S.H. Song, J.H. Park, G. Chitnis, R.A. Siegel, and B. Ziaie, "A Wireless Chemical Sensor with Iron Oxide Nanoparticles Embedded Hydrogel," Sens Act B, 193, 925-930 (2014). DOI: 10.1016/j.snb.2013.12.012
• G. Khushf and R.A. Siegel, “What is Unique about Nanomedicine? The Significance of the Mesoscale,” J Law Med Ethics, 40, 780-794 (2012). DOI: 10.1111/j.1748-720X.2012.00706.x
• I. Koonar, C. Zhou, M.A. Hillmyer, T.P. Lodge, and R.A. Siegel, “ABC TriblockTerpolymers Exhibiting Both Temperature- and pH-Sensitive Micellar Aggregation and Gelation in Aqueous Solution,” Langmuir, 28, 17785-17794 (2012). DOI: 10.1021/la303712b
• J.P.M. Motion, G.H. Huynh, F.C. Szoka, and R.A. Siegel, “Convection and Retro-Convection Enhanced Delivery: Some Theoretical Considerations Related to Drug Targeting,” Pharmaceut Res, 28, 472-479 (2011). DOI: 10.1007/s11095-010-0296-2
• R.A. Siegel, "Oscillatory Systems Created with Polymer Membranes, in Nonlinear Dynamics with Polymers," (J. Pojman and T-Q. Miyata, eds.), Wiley-VCH, Weinheim, pp. 189-217 (2010).
• R.A. Siegel and J.L. Linstad, “Cooperative Binding Isotherms for Nearest Neighbor Interacting Ligands on Platonic Solids: A Simple Model for Viral Capture Nanotherapy,” J Phys Chem B, 114, 14071-14076 (2010). DOI: 10.1021/jp1066378
• R.A. Siegel, Y. Gu, M. Lei, A. Baldi, E.E. Nuxoll, and B. Ziaie, "Hard and Soft Micro- and Nanofabrication: An Integrated Approach to Hydrogel Based Biosensing and Drug Delivery," J Controlled Release, 141, 303-313 (2010). DOI: 10.1016/j.jconrel.2009.12.012
• T. Vermonden, S.S. Jena, D. Barriet, R. Censi, J. van der Gucht, W.E. Hennink, and R.A. Siegel, "Macromolecular Diffusion in Self-Assembling Biodegradable Thermosensitive Hydrogels," Macromolecules, 43, 782-789 (2010). DOI: 10.1021/ma902186e
• V.D. Ivaturi, J.R. Riss, R.L. Kriel, R.A. Siegel, and J.C. Cloyd, "Bioavailability and Tolerability of Intranasal Diazepam in Healthy Adult Volunteers," Epilepsy Research, 84, 120-126 (2009). DOI: 10.1016/j.eplepsyres.2009.01.001
• E.E. Nuxoll, M.A. Hillmyer, R. Wang, C. Leighton, and R.A. Siegel, "Composite Block Polymer-Microfabricated Silicon Nanoporous Membrane," ACS Appl Mater Interf, 1, 888-893 (2009). DOI: 10.1021/am900013v
• D.F. Bayramov, P. Singh, G.W. Cleary, R.A. Siegel, A.E. Chalykh, and M.M. Feldstein, "Noncovalently Crosslinked Hydrogels Displaying a Unique Combination of Water Absorbing, Elastic and Adhesive Properties," Polym Int, 57, 785-790 (2008). DOI:10.1002/pi.2417
• H. Hou and R.A. Siegel, "Enhanced Permeation of Diazepam through Artificial Membranes from Supersaturated Solutions," J Pharm Sci, 95, 896-905 (2006). DOI: 10.1002/jps.20600
• M. Lei, A. Baldi, E. Nuxoll, R.A. Siegel, and B. Ziaie, "A Hydrogel-Based Implantable Micromachined Transponder for Wireless Glucose Measurement," Diabetes Tech Therap, 8, 112-122 (2006). DOI: 10.1089/dia.2006.8.112
• B. Ziaie, A. Baldi, M. Lei, Y. Gu, and R.A. Siegel, "Hard and Soft Micromachining for BioMEMS: Review of Techniques and Examples of Applications in Microfluidics and Drug Delivery," Adv Drug Deliv Revs, 56, 145-172 (2004). DOI: 10.1016/j.addr.2003.09.001
• G.P. Misra and R.A. Siegel, "A New Mode of Drug Delivery: Long-Term Autonomous Rhythmic Hormone Release Across a Hydrogel Membrane," J Controlled Release, 81, 1-6 (2002). DOI: 10.1016/s0168-3659(02)00043-3