Associate Professor Greg Walker

2025

Journal - Research Article

Krittaphol, W., Martin, L. W., Lamont, I. L., & Walker, G. F. (2025). A sensitive reverse-phase ultra performance liquid chromatography-tandem mass spectrometry method for the determination of tobramycin in Pseudomonas aeruginosa cell lysate. Journal of Pharmaceutical & Biomedical Analysis, 260, 116743. doi: 10.1016/j.jpba.2025.116743

Journal - Research Other

Krittaphol, W., Martin, L. W., Walker, G. F., & Lamont, I. L. (2025). Anaerobiosis and mutations can reduce susceptibility of Pseudomonas aeruginosa to tobramycin without reducing the cellular concentration of the antibiotic. Pathogens, 14, 187. doi: 10.3390/pathogens14020187

2024

Journal - Research Article

Nguyen, H. V., Campbell, K., Painter, G. F., Young, S. L., & Walker, G. F. (2024). Redox-responsive CpG-dextran conjugate enhances anti-tumour immunity following intratumoral administration. International Journal of Pharmaceutics, 664, 124621. doi: 10.1016/j.ijpharm.2024.124621

Conference Contribution - Verbal presentation and other Conference outputs

Shah, R. M., Reily-Bell, M. J., Walker, G., Katare, R., & Das, S. (2024, November). Investigating microRNAs biomarker potential and their encapsulation in cationic liposomes for targeted lung delivery. Verbal presentation at the School of Pharmacy Research Symposium, Dunedin, New Zealand.

2023

Conference Contribution - Published proceedings: Full paper

Shah, R. M., Lyu, A., Walker, G. F., Katare, R., & Das, S. C. (2023). Inhaled ceftazidime dry powder developed using spray freeze drying technique. Proceedings of the 34th Drug Delivery to the Lungs (DDL) Conference. 34, (pp. 320-323). doi: 10.60565/rt43-7m33

Conference Contribution - Published proceedings: Abstract

Draper, S., Minnell, J., McKenzie, R., Oh, S., Anderson, R., Compton, B., … Walker, G., … Painter, G. (2023). Ionisable lipid nanoparticle delivery systems for mRNA vaccines. Proceedings of the New Zealand Controlled Release Society (NZCRS) Symposium. Retrieved from http://nzcrs.org.nz/#/home

Shah, R. M., Reily-Bell, M., Katare, R., Walker, G. F., & Das, S. C. (2023). Preparation and characterisation of microRNA-loaded cationic liposomes for chronic obstructive pulmonary disease. Proceedings of the New Zealand Controlled Release Society (NZCRS) Symposium. Retrieved from http://nzcrs.org.nz/#/home

Shah, R. M., Reily-Bell, M., Katare, R., Walker, G., & Das, S. (2023). Development and evaluation of microRNA-134 encapsulated cationic liposomes for chronic obstructive pulmonary disease. Pharmacy Education, 23(6), (pp. 149). doi: 10.46542/pe.2023.236.129157

2022

Journal - Research Article

Nguyen, H. V., Campbell, K., Painter, G. F., Young, S. L., & Walker, G. F. (2022). Effect of carrier molecular weight on physicochemical properties and the in vitro immune-stimulatory activity of the CpG-dextran conjugates. International Journal of Pharmaceutics, 627, 122236. doi: 10.1016/j.ijpharm.2022.122236

McLaughlin, A. W., McDowell, A., Clarkson, A. N., & Walker, G. F. (2022). Characterization of poly(lactic-co-glycolic acid) nanofibers electrospun using a sustainable green chemistry with a low toxicity solvent system. International Journal of Polymeric Materials & Polymeric Biomaterials, 71(13), 983-992. doi: 10.1080/00914037.2021.1933976

Journal - Research Other

Liu, W., Price, S., Bennett, G., Maxwell, T. M. R., Zhao, C., Walker, G., & Bunt, C. (2022). A landscape review of controlled release urea products: Patent objective, formulation and technology. Journal of Controlled Release, 348, 612-630. doi: 10.1016/j.jconrel.2022.06.009

Conference Contribution - Poster Presentation (not in published proceedings)

Shah, R. M., Katare, R., Walker, G., & Das, S. C. (2022, November). Physicochemical characterization of exosome-mimetic nanoparticles for chronic obstructive pulmonary disease. Poster session presented at the New Zealand Controlled Release Society (NZCRS) Symposium, Auckland, New Zealand.

Conference Contribution - Verbal presentation and other Conference outputs

Shah, R., Walker, G., Katare, R., & Das, S. (2022, November). Spray-freeze drying: An emerging technique for producing inhalable microparticles of thermosensitive bioactives. Verbal presentation at the School of Pharmacy Research Day, Dunedin, New Zealand.

Nguyen, H. V., Campbell, K., Painter, G. F., Young, S. L., & Walker, G. F. (2022, November). Intratumoral delivery of immune-therapeutics: Effect of carrier molecular weight on the in vitro immune-stimulatory activity of the CpG-dextran conjugates. Verbal presentation at the New Zealand Controlled Release Society (NZCRS) Symposium, Auckland, New Zealand.

Shah, R., Walker, G., Katare, R., & Das, S. C. (2022, November). Spray-freeze drying: A hybrid particle engineering technique for producing highly porous and aerosolizable dry powder. Verbal presentation at the Bioengineering@Otago Showcase, [Online].

Shah, R. M., Walker, G. F., Katare, R., & Das, S. C. (2022, August-September). Differential regulation of microRNAs associated with COPD in smokers. Verbal presentation at the 16th New Zealand Medical Sciences Congress (MedSci), Queenstown, New Zealand.

2021

Journal - Research Article

Bērziņš, K., Fraser-Miller, S. J., Walker, G. F., Rades, T., & Gordon, K. C. (2021). Investigation on formulation strategies to mitigate compression-induced destabilization in supersaturated celecoxib amorphous solid dispersions. Molecular Pharmaceutics, 18, 3882-3893. doi: 10.1021/acs.molpharmaceut.1c00540

Liu, W., Walker, G., Price, S., Yang, X., Li, J., & Bunt, C. (2021). Electrospun membranes as a porous barrier for molecular transport: membrane characterization and release assessment. Pharmaceutics, 13(6), 916. doi: 10.3390/pharmaceutics13060916

Campbell, K., Young, V. L., Donaldson, B. C., Woodall, M. J., Shields, N. J., Walker, G. F., Ward, V. K., & Young, S. L. (2021). Delivering two tumour antigens survivin and mucin-1 on virus-like particles enhances anti-tumour immune responses. Vaccines, 9(5), 463. doi: 10.3390/vaccines9050463

Dowlath, S., Campbell, K., Al-Barwani, F., Young, V. L., Young, S. L., Walker, G. F., & Ward, V. K. (2021). Dry formulation of virus-like particles in electrospun nanofibers. Vaccines, 9(3), 213. doi: 10.3390/vaccines9030213

Davison, E. K., McGowan, J. E., Li, F. F., Harper, A. D., Young Jeong, J., Mros, S., Harbison-Price, N., Van Zuylen, E. M., Knottenbelt, M. K., Heikal, A., Ferguson, S. A., McConnell, M. A., Cook, G. M., Krittaphol, W., Walker, G. F., … Rennison, D. (2021). C-2 derivatized 8-sulfonamidoquinolines as antibacterial compounds. Bioorganic & Medicinal Chemistry, 29, 115837. doi: 10.1016/j.bmc.2020.115837

Journal - Research Other

Nguyen, H. V., Campbell, K., Painter, G. F., Young, S. L., & Walker, G. F. (2021). Data on the uptake of CpG-loaded amino-dextran nanoparticles by antigen-presenting cells [Data article]. Data in Brief, 35, 106883. doi: 10.1016/j.dib.2021.106883

2020

Journal - Research Article

Nguyen, H. V., Campbell, K., Painter, G. F., Young, S. L., & Walker, G. F. (2020). Nanoparticle system based on amino-dextran as a drug delivery vehicle: Immune-stimulatory CpG-oligonucleotide loading and delivery. Pharmaceutics, 12, 1150. doi: 10.3390/pharmaceutics12121150

McGowan, J. E., Harper, A. D., Davison, E. K., Jeong, J. Y., Mros, S., Harbison-Price, N., Van Zuylen, E. M., Knottenbelt, M. K., Heikal, A., Ferguson, S. A., McConnell, M. A., Cook, G. M., Krittaphol, W., Walker, G. F., … Rennison, D. (2020). Substituted sulfonamide bioisosteres of 8-hydroxyquinoline as zinc-dependent antibacterial compounds. Bioorganic & Medicinal Chemistry Letters, 30, 127110. doi: 10.1016/j.bmcl.2020.127110

2019

Journal - Research Article

Poller, B., Painter, G. F., & Walker, G. F. (2019). Influence of albumin in the microfluidic synthesis of PEG-PLGA nanoparticles. Pharmaceutical Nanotechnology, 7, 460-468. doi: 10.2174/2211738507666191023091938

Zawari, M., Poller, B., Walker, G., Pearson, A., & Carr, A. C. (2019). Formulation of broccoli sprout powder in gastro-resistant capsules protects against the acidic pH of the stomach in vitro but does not increase isothiocyanate bioavailability in vivo. Antioxidants, 8(9), 359. doi: 10.3390/antiox8090359

Journal - Research Other

Kramer, K., Young, S. L., & Walker, G. F. (2019). Data on the uptake of reducible antigen-adjuvant conjugates by dendritic cells [Data article]. Data in Brief, 23, 103759. doi: 10.1016/j.dib.2019.103759

Conference Contribution - Verbal presentation and other Conference outputs

Walker, G. (2019, December). Methane inhibitors. Verbal presentation at the Ag@Otago Symposium: New Zealand Agriculture 2050: Pathways of Innovation, Dunedin, New Zealand.

2018

Journal - Research Other

Donaldson, B., Lateef, Z., Walker, G. F., Young, S. L., & Ward, V. K. (2018). Virus-like particle vaccines: Immunology and formulation for clinical translation. Expert Review of Vaccines, 17(9), 833-849. doi: 10.1080/14760584.2018.1516552

Conference Contribution - Published proceedings: Abstract

Kramer, K., Donaldson, B., Young, V. L., Walker, G. F., Ward, V. K., & Young, S. L. (2018). Delivering tumour antigens survivin and mucin-1 on virus-like particles for breast cancer immunotherapy. Proceedings of the 41st Annual San Antonio Breast Cancer Symposium (SABCS). P4-06-20. Retrieved from https://www.sabcs.org/

Kramer, K., Donaldson, B., Young, V. L., Walker, G. F., Ward, V. K., & Young, S. L. (2018). Delivering tumour antigens survivin and mucin-1 on virus-like particles for breast cancer immunotherapy. Proceedings of the New Zealand Society for Oncology (NZSO) Conference. Retrieved from http://www.nzsoncology.org.nz/

2017

Journal - Research Article

Walker, G., Römann, P., Poller, B., Löbmann, K., Grohganz, H., Rooney, J. S., Huff, G. S., Smith, G. P. S., Rades, T., Gordon, K. C., Strachan, C. J., & Fraser-Miller, S. J. (2017). Probing pharmaceutical mixtures during milling: The potency of low frequency Raman spectroscopy in identifying disorder. Molecular Pharmaceutics, 14(12), 4675-4684. doi: 10.1021/acs.molpharmaceut.7b00803

Smith, G. P. S., McLaughlin, A., Clarkson, A. N., Gordon, K. C., & Walker, G. F. (2017). Raman microscopic imaging of electrospun fibers made from a polycaprolactone and polyethylene oxide blend. Vibrational Spectroscopy, 92, 27-34. doi: 10.1016/j.vibspec.2017.05.002

Kramer, K., Young, S. L., & Walker, G. F. (2017). Comparative study of 5′- and 3′-linked CpG–antigen conjugates for the induction of cellular immune responses. ACS Omega, 2(1), 227-235. doi: 10.1021/acsomega.6b00368

Poller, B., Strachan, C., Broadbent, R., & Walker, G. F. (2017). A minitablet formulation made from electrospun nanofibers. European Journal of Pharmaceutics & Biopharmaceutics, 114, 213-220. doi: 10.1016/j.ejpb.2017.01.022

Yarragudi, S. B., Richter, R., Lee, H., Walker, G. F., Clarkson, A. N., Kumar, H., & Rizwan, S. B. (2017). Formulation of olfactory-targeted microparticles with tamarind seed polysaccharide to improve nose-to-brain transport of drugs. Carbohydrate Polymers, 163, 216-226. doi: 10.1016/j.carbpol.2017.01.044

Kramer, K., Shields, N. J., Poppe, V., Young, S. L., & Walker, G. F. (2017). Intracellular cleavable CpG oligodeoxynucleotide-antigen conjugate enhances anti-tumor immunity. Molecular Therapy, 25(1), 62-70. doi: 10.1016/j.ymthe.2016.10.001

Conference Contribution - Published proceedings: Abstract

Kramer, K., Donaldson, B., Young, V. L., Walker, G. F., & Young, S. L. (2017). Co-delivery of survivin and mucin-1 on virus-like particles for breast cancer. In A. Blackman, L. Gillman, C. Oliver & D. Dantzic (Eds.), Proceedings of the Inaugural New Zealand Breast Cancer Symposium (NZBCS): United for a Cure through Research. (pp. 96). Auckland, New Zealand: Auckland University of Technology. [Abstract]

Kramer, K., Gaskarth, D., Walker, G. F., & Young, S. L. (2017). Intracellular cleavable antigen-adjuvant conjugates improve immunotherapy. Proceedings of the Third CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference. (pp. 173-174). Retrieved from http://www.cancerimmunotherapyconference.org

Conference Contribution - Verbal presentation and other Conference outputs

Kramer, K., Donaldson, B., Young, V. L., Walker, G. F., & Young, S. L. (2017, July). Developing a breast cancer immunotherapy. Verbal presentation at the New Zealand Branch of the Australasian Society for Immunology (NZ ASI) Annual Scientific Meeting, Christchurch, New Zealand.

2016

Conference Contribution - Published proceedings: Abstract

Kramer, K., Young, S. L., & Walker, G. F. (2016). Design of reversible antigen-adjuvant conjugates for triggered release inside antigen-presenting cells. Proceedings of the 14th Annual Meeting of the Association for Cancer Immunotherapy (CIMT). 39. Retrieved from http://www.cimt.eu/meetings/archive

Kramer, K., Young, S. L., & Walker, G. F. (2016). Design of intracellular cleavable immune-conjugates. European Journal of Immunology, 46(Suppl. 1), (pp. 810). doi: 10.1002/eji.201670200

Wise, L., Libuda, F., Real, N., Stuart, G., Wilkins, S., Wakelin, K., Mercer, A., Clarkson, A., Walker, G., … Theoret, C. (2016). Combined delivery of orf virus proteins VEGF-E and IL-10 dampens inflammation and promotes repair processes in equine skin wounds. Proceedings of the Diagnostics, Drugs, Devices, Discovery (D4) Conference. Retrieved from http://www.otago.ac.nz/d4/index.html

Rizwan, S. B., Yarragudi, S. B., Richter, R., Walker, G. F., & Clarkson, A. N. (2016). Olfactory-targeted microparticles: A novel approach to bypass the blood-brain barrier. In B. Leitch (Ed.), Proceedings of the 34th International Australasian Winter Conference on Brain Research. (pp. 60). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr

2015

Conference Contribution - Published proceedings: Abstract

Yarragudi, S. B., Ritcher, R., Walker, G. F., Clarkson, A. N., & Rizwan, S. B. (2015). Formulation of monodispursed mucoadhesive microparticles for nose-to-brain delivery. Proceedings of the Diagnostic Drug Device Discovery (D4) Conference. Retrieved from https://www.regonline.com.au/builder/site/Default.aspx?EventID=1758070

Kramer, K., Young, S., & Walker, G. (2015). Stability and activity of cleavable vaccine conjugates in vitro. Proceedings of the Diagnostic Drug Device Discovery (D4) Conference. Retrieved from https://www.regonline.com.au/builder/site/Default.aspx?EventID=1758070

Yarragudi, S. B., Walker, G. F., Clarkson, A. N., & Rizwan, S. B. (2015). Scanning electron microscopy as a tool to understand the effects of process variables on microparticle formation. Proceedings of the 27th National Conference on Microscopy. Retrieved from http://microscopy2015.otago.ac.nz/index.html

Conference Contribution - Poster Presentation (not in published proceedings)

Kramer, K., Young, S., & Walker, G. (2015, October). Reversible adjuvant conjugation to a model tumour antigen enhances CD4+ and CD8+ T-cell proliferation in vitro. Poster session presented at the Otago Spotlight Series: Cancer Research, Wellington, New Zealand.

2014

Conference Contribution - Poster Presentation (not in published proceedings)

Kramer, K., Young, S. L., & Walker, G. F. (2014, May). CpG conjugation to model tumour antigen ovalbumin leads to enhanced CD8⁺ T-cell proliferation. Poster session presented at the 12th Annual Meeting of the Association for Cancer Immunotherapy (CIMT), Mainz, Germany.

Kramer, K., Young, S., & Walker, G. (2014, November). Development of cleavable antigen-adjuvant conjugates that are triggered by intracellular glutathione. Poster session presented at the Devices for Diagnostics and Drug Delivery (D4) Conference, Dunedin, New Zealand.

Yarragudi, S., Walker, G., Clarkson, A., & Rizwan, S. (2014, November). Formulation and characterisation of a novel microparticle system for nose-to-brain drug delivery. Poster session presented at the Devices for Diagnostics and Drug Delivery (D4) Conference, Dunedin, New Zealand.

McLaughlin, A., Berretta, A., Clarkson, A., & Walker, G. (2014, November). An alternative solvent system for electrospinning polycaprolactone. Poster session presented at the Devices for Diagnostics and Drug Delivery (D4) Conference, Dunedin, New Zealand.

Wilkins, S., Wise, L., Walker, G., Libuda, F., & Real, N. (2014, November). Engineering electrospun nanofibres with orf virus proteins for improved wound healing. Poster session presented at the Devices for Diagnostics and Drug Delivery (D4) Conference, Dunedin, New Zealand.

2013

Conference Contribution - Published proceedings: Abstract

Xia, L., McLaughlin, A., & Walker, G. (2013). Controlled release from a single- and dual-layered electrospun nanofiber textile device. Proceedings of 15th Conference on Formulation and Delivery of Bioactives: Found in Translation. Retrieved from http://bioactives.otago.ac.nz/

Kao, I., Walker, G., Priemel, P., McDowell, A., Thomas, N., Rades, T., Kieser, J., & Bushby, S. (2013). Effect of antidepressants on growth of Lucilia sericata larvae. Proceedings of 15th Conference on Formulation and Delivery of Bioactives: Found in Translation. Retrieved from http://bioactives.otago.ac.nz/

McLaughlin, A., Walker, G., & Clarkson, A. (2013). Controlled release of the nootropic drug L-655,708 from hydrogels. Proceedings of 15th Conference on Formulation and Delivery of Bioactives: Found in Translation. Retrieved from http://bioactives.otago.ac.nz/

Walker, G. (2013). Developing of new haemostat to control surgical bleeding. Proceedings of 15th Conference on Formulation and Delivery of Bioactives: Found in Translation. Retrieved from http://bioactives.otago.ac.nz/

Conference Contribution - Verbal presentation and other Conference outputs

Walker, G. (2013, December). Design of bioresponsive deshielding nanoparticle systems. Verbal presentation at the Formulation and Delivery of Bioactives Research Theme One Day Forum: Triggered Delivery Systems, Dunedin, New Zealand.

2010

Intellectual Property

Goodall, A. H., Taylor, S. M., & Walker, G. F. (2010). Therapeutic Agent. (GB2429153).

2008

Journal - Research Article

Fella, C., Walker, G. F., Ogris, M., & Wagner, E. (2008). Amine-reactive pyridylhydrazone-based PEG reagents for pH-reversible PEI polyplex shielding. European Journal of Pharmaceutical Sciences, 34(4-5), 309-320. doi: 10.1016/j.ejps.2008.05.004

DeRouchey, J., Schmidt, C., Walker, G. F., Koch, C., Plank, C., Wagner, E., & Rädler, J. O. (2008). Monomolecular assembly of siRNA and Poly(ethylene glycol)—peptide copolymers. Biomacromolecules, 9(2), 724-732. doi: 10.1021/bm7011482

2007

Journal - Research Article

Knorr, V., Allmendinger, L., Walker, G. F., Paintner, F. F., & Wagner, E. (2007). An acetal-based PEGylation reagent for pH-sensitive shielding of DNA polyplexes. Bioconjugate Chemistry, 18, 1218-1225. doi: 10.1021/bc060327a

2006

Conference Contribution - Verbal presentation and other Conference outputs

Walker, G. (2006, November). Development of a platelet substitute. Verbal presentation at the Pharmacy School Seminar Series, Dunedin, New Zealand.

2002

Journal - Research Article

Ledger, R., Tucker, I. G., & Walker, G. F. (2002). The metabolic barrier of the lower intestinal tract of salmon to the oral delivery of protein and peptide drugs. Journal of Controlled Release, 85, 91-103.

Ledger, R., Tucker, I. G., & Walker, G. F. (2002). Quantitative capillary electrophoresis assay for the proteolytic stability of luteinizing hormone-releasing hormones. Journal of Chromatography B, 769, 235-242.

2001

Journal - Research Article

Walker, G. F., Ledger, R., & Tucker, I. G. (2001). Activity of pancreatic endopeptidases towards luteinizing hormone-releasing hormones. International Journal of Pharmaceutics, 216, 77-82.

1999

Journal - Research Article

Walker, G., Ledger, R., & Tucker, I. G. (1999). Garbomer inhibits tryptic proteolysis of luteinizing hormone-releasing hormone and N-alpha-benzoyl-L-arginine ethyl ester by binding the enzyme. Pharmaceutical Research, 16(7), 1074-1080.

1998

Conference Contribution - Published proceedings: Abstract

Walker, G. F., Ledger, R., & Tucker, I. G. (1998). Distribution of proteolytic enzymes in the lumen of the lower intestinal tract of salmon. Pharmaceutical Research, 14, (pp. S153). [Abstract]

Walker, G., Ledger, R., & Tucker, I. G. (1998). Susceptibility of human and salmon lutenising hormone-releasing hormone (LHRH) to metabolism in the salmon intestinal lumen and mucosal homogenates and their protection by various protease inhibitors. Proceedings from the Annual Meeting of the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists. [Abstract]

1995

Conference Contribution - Published proceedings: Abstract

Walker, G. F., Ledger, R., & Tucker, I. G. (1995). Partition coefficients of human and salmon luteinising hormone releasing hormone (LHRH). Abstracts of the Australasian Pharmaceutical Science Association Conference. 15, (pp. 15). Auckland. [Abstract]