Our Published Research

 *undergraduate student, #graduate student/postdoc, +corresponding author

63. Sharma, V.#, Manchester, L., Holstein, M., Xu, X., Ghose, S., and Heldt, C.L.+ (2025) Impact of Eco-Friendly Surfactant Structure and Class on Enveloped Virus Inactivation. Biotechnology Journal, 20(4) e70023. DOI: 10.1002/biot.70023

62. Nold, N.M.#, Waldack, S.*, James, G. *, Colling, T., Manchester, L., Sarvari, T.#, Bekkala, A., Kriz, S.A. #, Baldwin, M.*, Augstin-Mazariegos, E.*, Betenbaugh, M.J., and Heldt, C.L.+. (2025) Continuous Purification of a Parvovirus Using Two Aqueous Two-Phase Extraction Steps. Biotechnology Progress. Accepted. DOI: 10.1002/btpr.70034

61. Kriz, S.A.# and Heldt, C.L+ (2025) Rapid optimization by experimental and model-based approaches for biomolecule separation in aqueous two-phase systems. Journal of Chromatography A. 1749, 465881. DOI: 10.1016/j.chroma.2025.465881

60. Nold, N.M.#, Kriz, S.A. #, Waldack, S.*, James, G. *, Colling, T., Sarvari, T.#, Sharma, V.#, Pohkrel, A. *, Burghardt, E. *, Joshi, P.U. #, and Heldt, C.L.+ (2025) Purification of a Non-Enveloped Virus using Sequential Aqueous Two-Phase Extraction. Journal of Chromatography A. 1748, 465866. DOI: 10.1016/j.chroma.2025.465866

59. Zajac, J.W.P., Muralikrishnan, P., Tohidian, I#, Zeng, X., Heldt, C.L., Perry, S.L., and Sarupria, S.+ (2025) Flipping Out: Role of Arginine in Hydrophobic Interaction and Biological Formulation Design. Chemical Science. Accepted.  DOI: 10.1039/D4SC08672D

58. Zajac, J., Muralikrishnan, P., Heldt, C.L., Perry, S.L., and Sarupria, S+. (2025) Towards Stable Biologics: Understanding Co-Excipient Effects on Hydrophobic Interactions and Solvent Network Integrity. Molecular Systems Design & Engineering. Accepted. doi: 10.1039/D4ME00201F.

57. Sharma, V.#,^, Singh, S.#,^, Nold, N.M.#, Kaur, S., Li, B., and Heldt, C.L.+ (2025) Viral clearance of cupric-modified phyllosilicate minerals against enveloped and non-enveloped viruses. Colloids and Interfaces. 9(1), 13.

https://doi.org/10.3390/colloids9010013

 *undergraduate student, #graduate student/postdoc, +corresponding author

56. Heldt, C.L.+, Skinner, M.A.#, and Anand, G.S. (2024) Structural Changes Likely Cause Chemical Differences Between Empty and Full AAV Capsids. Biomedicines. 12 (9), 2128. doi: 10.3390/biomedicines12092128

55. Razaviamri, F., Singh, S.#, Manuel, J., Zhang, Z., Manchester, L., Heldt, C.L., and Lee, B.P.+ (2024) Utilizing Rapid Hydrogen Peroxide Generation from 6-Hydroxycatechol to Design Moisture-Activated, Self-Disinfecting Coating. ACS Applied Materials & Interfaces 16 (21), 26998–27010. doi: 10.1021/acsami.4c00213 

54. Ding, X. +, Zhang, Z., Kluka, C., Asim, S., Manuel, J., Lee, B.P., Jiang, J., Heiden. P.A., Heldt, C.L., Rizwan, M. (2024) A pair of functional polyesters that are photo-crosslinkable and electrospinnable to engineer elastomeric scaffolds with tunable structure and properties. ACS Applied Bio Materials. 7(2), 863-878. DOI: 10.1021/acsabm.3c00894 

53. Heldt, C.L.+ (2024) Chapter 28 – Virus removal in bioprocessing using charged media. In Ion-Exchange Chromatography and Related Techniques (eds P.N. Nesterenko, C.F. Poole, and Y.Sun). Elsevier. 579-590.

52. Joshi, P.U.#, Decker, C.*, Zeng, X., Sathyavageeswaran, A., Perry, S.L.+, and Heldt, C.L.+ (2024) Design Rules for the Sequestration of Viruses into Polypeptide Complex Coacervates. Biomacromolecules. Accepted. DOI: 10.1021/acs.biomac.3c00938

51. Nold, N.M.#, Pearson, E.#, and Heldt, C.L.+ (2024) Economic Comparison of Batch and Continuous Aqueous Two-Phase Purification for Viral Products. Biotechnology Progress. Accepted. DOI: 10.1002/btpr.3397

 *undergraduate student, #graduate student/postdoc, +corresponding author

50. Heldt, C.L.+, Areo, O.#, Joshi, P.U.#, Mi, X.#, Ivanova, Y., and Berrill, A. (2023) Empty and Full AAV Capsid Charge and Hydrophobicity Differences Measured with Single Particle AFM. Langmuir. 39(16), 5641-5648. doi: 10.1021/acs.langmuir.2c02643

49. Joshi, P.U.#, Kroger, S.M., Zustiak, S.P., and Heldt, C.L.+ (2023) Multimodal Peptide Ligand Extracts Parvovirus from Interface in Affinity Aqueous Two-Phase System. Biotechnology Progress. Accepted. doi: 10.1002/btpr.3338. PMID: 36891815

48. Lim, X.C., Huang,C., Yatim, S.M.J.M., Chong, S.Y., Tan, S.H., Yang, X., Pedersen, J.* Talanker, M.* Heldt, C.L., Modh, H., Wacker, M.G., Pastorin, G., Chan, S.P., Richards, A.M., Charles, C.J., Chan, M.Y.+, Wang, J.W.+ (2023) Temporal changes of hemostatic proteins in extracellular vesicles presage reverse left ventricular remodeling in acute myocardial infarction. International Journal of Molecular Sciences. 24, 327. doi: 10.3390/ijms24010327

 *undergraduate student, #graduate student/postdoc, +corresponding author

47. Obrenovich, M.E.+, Heldt, C.L., Tayahi, M., and Enancipator, S.N. (2022) Prophylaxis and Remediation for Future Pandemic Pathogens–(Lessons from a post-Covid world). Microorganisms. 10, 2407. doi: 10.3390/microorganisms10122407

46. Sorci, M., Fink,T.D., Sharma, V.#, Singh, S.#, Arduini, B., Dovidenko,K., Heldt,C.L., Palermo,E.F.+, and Zha, R.H.+. (2022) Virucidal N95 Respirator Face Masks via Ultrathin Surface-Grafted Quaternary Ammonium Polymer Coatings. ACS Applied Materials and Interfaces. 14(22) 25135-25146. doi: 10.1021/acsami.2c04165.

45. Singh, N.+ and Heldt, C.L.+ (2022) Challenges in Downstream Purification of Gene Therapy Viral Vectors. Current Opinion in Chemical Engineering. 35, 100780. doi: 10.1016/j.coche.2021.100780.

44. Joshi, P.U. #, Meingast, C.L. #, Xu, X., Hostein, M., Feroz, H., Ranjan, S., Ghose, S., Li, Z.J., and Heldt, C.L.+ (2022) Virus Inactivation at Moderately Low pH Varies with Virus and Buffer Properties. Biotechnology Journal. 17(2) 2100320.  doi: 10.1002/biot.202100320.

 *undergraduate student, #graduate student/postdoc, +corresponding author

43. Areo, O.#, Joshi, P.U.#, Obrenovich, M, Tayahi, M., and Heldt. C.L.+ (2021) Single-Particle Characterization of SARS-CoV-2 Isoelectric Point and Comparison to Variants of Interest. Microorganisms. 9(8), 1606. doi: 10.3390/microorganisms9081606.

42. Joshi,P.U.#, Turpeinen, D.G. #, Schroeder, M.*, Jones, B.*, Lyons, A.*, Kriz, S.A.#, Khaksari, M., O’Hagan, D., Nikam, S., and Heldt, C.L.+ (2021) Osmolyte Enhanced Aqueous Two-Phase System for Virus Purification. Biotechnology and Bioengineering. 118 (8): 3251-3262. doi: 10.1002/bit.27849

41. Turpeinen, D.G. #, Joshi,P.U.#, Kriz, S.A.#, Kaur, S., Nold, N.M.#, O’Hagen, D., Nikam, S., Massoud, H., and Heldt, C.L.+ (2021) Continuous Downstream Purification of Viral Products Using an Aqueous Two-Phase System. Separation and Purification Technology. 269: 118753. doi: 10.1016/j.seppur.2021.118753

40. Meingast, C.L. #, Joshi, P.U. #, Turpeinen, D.G. #, Xu, X., Hostein, M., Feroz, H., Ranjan, S., Ghose, S., Li, Z.J., and Heldt, C.L.+. (2021) Physiochemical Properties of Enveloped Viruses and Arginine Dictate Inactivation. Biotechnology Journal. Accepted. https://doi.org/10.1002/biot.202000342.

 *undergraduate student, #graduate student/postdoc, +corresponding author

39. Mi, X.#, Blocher McTigue, W.C., Joshi,P.U.#, Bunker,M.K.*, Heldt,C.L.+ and Perry, S.L.+ (2020) Stabilization of Viruses: A Stepping Stone toward Thermostable Vaccines. Biomaterials Science. 8, 7082. (invited paper) doi: 10.1039/d0bm01433h

38. Mi, X.#, Albukhari, S.M., Heldt, C.L.+, and Heiden, P.A.+ (2020) Virus and chlorine adsorption onto guanidine modified cellulose nanofibers using covalent and hydrogen bonding. Carbohydrate Research. 498, 108153. doi: 10.1016/j.carres.2020.108153

37. Kord Forooshani, P., Pinnaratip, R., Polega, E., Tyo, A., Pearson, E. #, Liu, B., Folayan, T.O., Pan, L., Rajachar, R., Heldt, C.L.  and Lee, B.+ (2020) Hydroxyl Radical Generation Through the Fenton-Like Reaction of Hematin- and Catechol-Functionalized Microgels. Chemistry of Materials. 32 (19) 8182-8194. doi: 10.1021/acs.chemmater.0c01551

36. Mi, X.# and Heldt, C.L.+ (2020) Single-particle chemical force microscopy to characterize virus surface chemistry. BioTechniques. 69 (5), 363-370. doi: 10.2144/btn-2020-0085

35. Joonaki, E.+ Hassanpouryouzband, A., Heldt, C.L., and Areo, O.# (2020) Surface Chemistry Can Unlock Drivers of Surface Stability of SARS-CoV-2 onto the Surfaces in Variety of Environmental Conditions. Chem. 6(9), 2135-2146. doi: 10.1016/j.chempr.2020.08.001

34. Habibi, S., Joshi, P.U. #, Mi, X. #, Heldt, C.L., and  Minerick, A.M.+ (2020) Changes in membrane dielectric properties of porcine kidney cells provide insight into the antiviral activity of glycine. Langmuir. 36 (29), 8344-8356. doi: 10.1021/acs.langmuir.0c00175

33. Mi, X. #, Bromley, E.K.*, Joshi, P.U. #, Long, F., and Heldt, C.L.+ (2020) Virus isoelectric point determination using single-particle chemical force microscopy. Langmuir. 36, 370-378. doi: 10.1021/acs.langmuir.9b03070. Highlighted in BioTechniques by Katie Gordon. Mar 23, 2020.

32. Meingast, C.L. #, and Heldt, C.L.+. (2020) Exploring the Mechanism of Arginine Enveloped Virus Inactivation. Biotechnol Prog. 36(2), e2931. doi: 10.1002/btpr.2931

 *undergraduate student, #graduate student/postdoc, +corresponding author

31. Joshi, P.U. #, Weiss, M.*, Corbin-Escalante, G.*, Schroeder, M.*,and Heldt, C.L.+. (2019) Tie Line Framework to Optimize Non-Enveloped Virus Recovery in Aqueous Two-Phase Systems. Journal of Chromatography B. 1126-1127. 121744. doi: 10.1016/j.jchromb.2019.121744

30. Mi, X. #, Lucier, E.M.*, Turpeinen, D. G. #, Yeo, E.L.L, Kah, J.C.Y.+, and Heldt, C.L.+. (2019) Mannitol-induced gold nanoparticle aggregation for the ligand-free detection of viral particles. Analyst. 144: 5486-5496. doi: 10.1039/C9AN00830F

29. Heldt,C.L.+ (2019) Scalable method utilizing low pH for DNA removal in the harvest of recombinant adeno-associated virus vectors. Journal of Chromatography B. 1124. 173-179. doi: 10.1016/j.jchromb.2019.06.011

28. Meng, H., Forooshani, P.K, Joshi, P.U. #, Osborne, J., Mi, X. #, Meingast, C. #, Kelley, J., Narkar, A.R., He, W., Frost, M.C., Heldt, C.L., and Lee, B.P.+ (2019) Biomimetic Recyclable Microgels for On Demand Generation of Hydrogen Peroxide and Antipathogenic Application. Acta Biomaterialia. 83(1). 109-118.

 *undergraduate student, #graduate student/postdoc, +corresponding author

27. Heldt,C.L.+, Smith, E., Cunningham, H.*, and Miller, C.* (2018) Mentoring Students in Research and Communication Across the Ocean. PURM 7.1. https://blogs.elon.edu/purm/2013/04/12/archives/

26. Heldt,C.L.+, Saksule, A. #, Joshi, P.U. #, and Ghafarian, M. # (2018) A Generalized Purification Step for Viral Particles Using Mannitol Flocculation. Biotechnology Progress. 34(4): 1027-1035.

25. Heldt,C.L.+, Nwamba, C., Radecki, B., Colvard, D., and Czeka, S. (2018) Environmental research to engage community college students. ASEE North Central Conference Proceedings. Spring.

 *undergraduate student, #graduate student/postdoc, +corresponding author

24. Heldt,C.L.+, Zahid,A.*, Vijayaragavan,K.S. # and Mi, X. # (2017) Experimental and Computational Surface Hydrophobicity Analysis of a Non-enveloped Virus and Proteins. Colloids and Surfaces B. 153: 77-84.

 *undergraduate student, #graduate student/postdoc, +corresponding author

23. Saha, D.+, Heldt, C. L., Gencoglu, M.F. #, Vijayaragavan,K.S. #, Chen, J., and Saksule,A. # (2016) A Study on the Cytotoxicity of Carbon-based Materials. Material Science and Engineering C. 68, 101-108.

22. Pearce, J.M.+, Anzalone, N.C.*, and Heldt, C. L. (2016) Open-source Wax RepRap 3-D Printer for Rapid Prototyping Paper-Based Microfluidics. Journal of Laboratory Automation.  21(4), 510-516.

21. Heldt, C. L.+, Bank, A. *, Turpinen, D. T. * & King, J. A. (2016) Translating University Biosensor Research to a High School Laboratory Experience. Chemical Engineering Education. 50(1), 70-75.

 *undergraduate student, #graduate student/postdoc, +corresponding author

20. Gencoglu, M. F. # and Heldt, C. L.+. (2015) Enveloped Virus Flocculation and Removal in Osmolyte Solutions. Journal of Biotechnology.  206, 8-11.

 *undergraduate student, #graduate student/postdoc, +corresponding author

19. Gencoglu, M. F#., Spurri, A.*, Franko, M.*, Chen, J., Hansley, D. K., Heldt, C. L.+, Saha, D.+ (2014) Biocompatibility of Soft-templated Mesoporous Carbons. ACS Applied Materials & Interfaces.  6, 15068-15077.

18. Vijayaragavan, K. S. #, Zahid, A.*, Young, J.W.* and Heldt, C. L.+ (2014).  Separation of porcine parvovirus from bovine serum albumin using PEG-salt aqueous two-phase system. Journal of Chromatography B 967, 118-126.

17.  Mi, X# and Heldt, C. L.+ (2014) Adsorption of a non-enveloped mammalian virus to functionalized nanofibers. Colloids and Surfaces B: Biointerfaces 121, 319-324.

16. Gencoglu, M. F. #, Pearson, E.* and Heldt, C. L.+ (2014). Porcine Parvovirus Flocculation and Removal in the Presence of Protecting Osmolytes.  Journal of Biotechnology 186, 83-90.

15.  Xie, H., Tewari, R., Fukushima, H., Narendra, J., Heldt, C. L., King, J. A. and Minerick, A. R.+ (2014). Development of a 3D graphene electrode dielectrophoresis device.  Journal of Visualized Experiments. 88, e51696.

14. Mi, X. #, Vijayaragavan, K. S. # and Heldt, C. L.+ (2014). Virus Adsorption of Water-Stable Quaternized Chitosan Nanofibers.  Carbohydrate Research, 387: 24-29.

 *undergraduate student, #graduate student/postdoc, +corresponding author

13.  Bai, B. #, Mi, X. #, Xiang, X., Heiden, P. A. and Heldt, C. L.+ (2013). Non-Enveloped Virus Reduction with Quaternized Chitosan Nanofibers Containing Graphene. Carbohydrate Research 380, 137-142.

12.  Tafur, M. F. #, Vijayaragavan, K. S. # and Heldt, C. L.+ (2013). Reduction of Porcine Parvovirus Infectivity in the Presence of Protecting Osmolytes. Antiviral Research 99, 27-33.

11.  Heldt, C. L.+, Sieloff, A. M.*, Merillat, J. P.*, Minerick, A. R., King, J. A., Perger, W. F., Fukushima, H. and Narendra, J. (2013). Stacked graphene nanoplatelet paper sensor for protein detection. Sensors and Actuators B: Chemical 181, 92-98.

10. Zonca, M. R., Yune, P. S., Heldt, C. L., Belfort, G. and Xie, Y. (2013). High-Throughput Screening of Substrate Chemistry for Embryonic Stem Cell Attachment, Expansion, and Maintaining Pluripotency. Macromolecular Bioscience 13, 177-190.

9. Sorci, M., Gu, M., Heldt, C. L., Grafeld, E.* and Belfort, G. (2013). A multi-dimensional approach for fractionating proteins using charged membranes. Biotechnology and Bioengineering 110, 1704-1713.

 *undergraduate student, #graduate student/postdoc, +corresponding author

8. Heldt, C. L.+ (2012). Peer Evaluation in Chemical Engineering Capstone Design Via Wikis. Chemical Engineering Education 46, 189-195.

7. Heldt, C. L., Gurgel, P. V., Jaykus, L. A. and Carbonell, R. G. (2012). Porcine parvovirus removal using trimer and biased hexamer peptides. Biotechnology Journal 7, 558-565.

 *undergraduate student, #graduate student/postdoc, +corresponding author

6. Heldt, C. L., Kurouski, D., Sorci, M., Grafeld, E.*, Lednev, I. K. and Belfort, G. (2011). Isolating toxic insulin amyloid oligomers that lack b-sheets and have wide pH stability. Biophysical Journal 100, 2792-2800.

5. Heldt, C. L., Zhang, S.* and Belfort, G. (2011). Asymmetric Amyloid Fibril Elongation: A New Perspective on a Symmetric World. Proteins 79, 92-98. Highlighted in C&E News, Nov 2010.

4. Heldt, C. L., Sorci, M., Posada, D., Hirsa, A. and Belfort, G. (2011). Detection and Reduction of Microaggregates in Insulin Preparations. Biotechnology and Bioengineering 108, 237-241.

 *undergraduate student, #graduate student/postdoc, +corresponding author

3. Heldt, C. L., Gurgel, P. V., Jaykus, L. A. and Carbonell, R. G. (2009). Influence of Peptide Ligand Surface Density and Ethylene Oxide Spacer Arm on the Capture of Porcine Parvovirus. Biotechnology Progress 25, 1411-1418.

 *undergraduate student, #graduate student/postdoc, +corresponding author

2. Heldt, C. L., Gurgel, P. V., Jaykus, L. A. and Carbonell, R. G. (2008). Identification of Trimeric Peptides That Bind Porcine Parvovirus from Mixtures Containing Human Blood Plasma. Biotechnology Progress 24, 554-560.

 *undergraduate student, #graduate student/postdoc, +corresponding author

1. Heldt, C. L., Hernandez, R., Mudiganti, U., Gurgel, P. V., Brown, D. T. and Carbonell, R. G. (2006). A colorimetric assay for viral agents that produce cytopathic effects. Journal of Virological Methods 135, 56-65.