Hamish S Christie

Interests

No activities entered.

Courses

Scholarly Contributions

Books

• Christie, H. S., & Padias, A. B. (2016). Organic Chemistry Laboratory Manual. Hayden-McNeil.

Journals/Publications

• Arce, F. T., Aspinwall, C. A., Christie, H. S., Fonseka, N. M., & Saavedra, S. S. (2021).

  Nanomechanical Properties of Artificial Lipid Bilayers Composed of Fluid and Polymerizable Lipids

  . Langmuir, 38(1), 100-111. doi:10.1021/acs.langmuir.1c02098
  More info

  Polymerization enhances the stability of a planar supported lipid bilayer (PSLB) but it also changes its chemical and mechanical properties, attenuates lipid diffusion, and may affect the activity of integral membrane proteins. Mixed bilayers composed of fluid lipids and poly(lipids) may provide an appropriate combination of polymeric stability coupled with the fluidity and elasticity needed to maintain the bioactivity of reconstituted receptors. Previously (Langmuir, 2019, 35, 12483-12491) we showed that binary mixtures of the polymerizable lipid bis-SorbPC and the fluid lipid DPhPC form phase-segregated PSLBs composed of nanoscale fluid and poly(lipid) domains. Here we used atomic force microscopy (AFM) to compare the nanoscale mechanical properties of these binary PSLBs with single-component PSLBs. The elastic (Young's) modulus, area compressibility modulus, and bending modulus of bis-SorbPC PSLBs increased upon polymerization. Before polymerization, breakthrough events at forces below 5 nN were observed, but after polymerization, the AFM tip could not penetrate the PSLB up to an applied force of 20 nN. These results are attributed to the polymeric network in poly(bis-SorbPC), which increases the bilayer stiffness and resists compression and bending. In binary DPhPC/poly(bis-SorbPC) PSLBs, the DPhPC domains are less stiff, more compressible, and are less resistant to rupture and bending compared to pure DPhPC bilayers. These differences are attributed to bis-SorbPC monomers and oligomers present in DPhPC domains that disrupt the packing of DPhPC molecules. In contrast, the poly(bis-SorbPC) domains are stiffer and less compressible relative to pure PSLBs; this difference is attributed to DPhPC filling the nm-scale pores in the polymerized domains that are created during bis-SorbPC polymerization. Thus, incomplete phase segregation increases the stability of poly(bis-SorbPC) but has the opposite, detrimental effect for DPhPC. Overall, these results provide guidance for the design of partially polymerized bilayers for technological uses.
• Christie, H. S., Saavedra, S. S., Aspinwall, C. A., Teran Arce, P. F., & Fonseka, N. M. (2022). Nanomechanical Properties of Artificial Lipid Bilayers Composed of Fluid and Polymerizable Lipids. Langmuir, 38, 100-111. doi:https://doi.org/10.1021/acs.langmuir.1c02098
• Christie, H. S., & Vitaku, E. (2019).

  Improved Procedure for Bleach-Based Alcohol Oxidation in Undergraduate Laboratories

  . Journal of Chemical Education, 96(5), 1042-1045. doi:10.1021/acs.jchemed.8b00710
  More info

  A reliable method for bleach-based alcohol oxidation has been developed. Use of sodium bisulfate as the acid additive in the reaction mixture eliminates the various problems associated with acetic acid, which has commonly been used for this type of oxidation. By conducting the reaction in an ethyl acetate/water two-phase reaction mixture, efficient reaction occurs at room temperature, and the workup is straightforward. This more reliable version of the well-known transformation has been successfully performed by thousands of second-year undergraduate organic chemistry students over the last several years.
• Christie, H. S., & Vitaku, E. (2019). Improved Procedure for Bleach-Based Alcohol Oxidation in Undergraduate Laboratories. Journal of Chemical Education, 96(5), 1042-1045. doi:10.1021/acs.jchemed.8b00710
  More info

  A publication describing a useful oxidation experiment for use in second-year organic chemistry undergraduate laboratory classes.
• Christie, H. S., Aspinwall, C. A., Saavedra, S. S., Fonseka, M. N., Liang, B., Orosz, K. S., Jones, I. W., & Hall Jr, H. (2019). Nanodomain Formation in Planar Supported Lipid Bilayers Composed of Fluid and Polymerized Dienoyl Lipids. Langmuir, 35, 12483-12491. doi:10.1021/acs.langmuir.9b02101

Presentations

• Christie, H. S., Lachance, Z. T., & Pemberton, J. E. (2018, July/summer). Teaching Green Chemistry and Sustainability in the Secondary Classroom – A Course for In-Service High School Teachers. 25th Biennial Conference on Chemical Education. Notre Dame, IN: American Chemical Society Division of Chemical Education.
  More info

  Presented a talk at the 25th Biennial Conference on Chemical Education
• Lachance, Z. L., Christie, H. S., & Pemberton, J. E. (2016, Summer). Green and Sustainable Chemistry in Secondary Education. 252nd American Chemical Society National Meeting & Exposition. Philadelphia, PA: American Chemical Society.
• Christie, H. S. (2014, August). Safe, easily constructed apparatus for liquid CO2 extractions. 2014 Biennial Conference on Chemical Education. Grand Valley State University, Allendale MI, August 3-7, 2014: American Chemical Society.
• Christie, H. S., & Vitaku, E. (2014, August). Straightforward procedure using bleach for the green oxidation of alcohols. 2014 Biennial Conference on Chemical Education. Grand Valley State University, Allendale MI, August 3-7, 2014.: American Chemical Society.

Poster Presentations

• Lachance, Z. L., Christie, H. S., & Pemberton, J. E. (2016, Summer). Green and Sustainable Chemistry in Secondary Education. 2016 Biennial Conference on Chemical Education (BCCE). Greeley, CO: BCCE.