CHE1CHF Introduction to Chemistry

CHE2NAC  Nanochemistry

CHE3ADB Surface Chemistry

CHE4HNA Honours Chemistry

Selected publications:

Exploring the origin of tip-enhanced Raman scattering; preparation of efficient TERS probes with high yield Author(s): Asghari-Khiavi, Mehdi; Wood, Bayden R.; Hojati-Talemi, Pejman; et al. Source: Journal of Raman Spectroscopy Volume: 43 Issue: 2 Pages: 173-180 Published: 2012

Surface Immobilization of Bio-Functionalized Cubosomes: Sensing of Proteins by Quartz Crystal Microbalance Author(s): Fraser, S. J.; Mulet, X.; Martin, L.; et al. Source: Langmuir Volume: 28 Issue: 1 Pages: 620-627 Published: 2012

Near-field diffraction in a two-dimensional V-groove and its role in SERS Author(s): Mechler, M.; Kukhlevsky, S. V.; Mechler, A.; et al. Source: Physical Chemistry Chemical Physics Volume: 13 Issue: 46 Pages: 20772-20778 Published: 2011

Correlation of atomic force microscopy and Raman micro-spectroscopy to study the effects of ex vivo treatment procedures on human red blood cells Author(s): ASGHARI-KHIAVI, M; WOOD, BR; MECHLER, A; et al. Source: Analyst Volume: 135 Issue: 3 Pages: 525-530 Published: 2010 

Electrochemiluminescence of surface bound microparticles of ruthenium complexes Author(s): BARBANTE, GJ; HOGAN, CF; MECHLER, A; et al. Source: Journal of Materials Chemistry Volume: 20 Issue: 5 Pages: 891-899 Published: FEB 7 2010 

Multifunctional protein nanocarriers for targeted nuclear gene delivery in nondividing cells Author(s): GLOVER, DJ; NG, SM; MECHLER, A; et al. Source: FASEB JOURNAL Volume: 23 Issue: 9 Pages: 2996-3006 Published: SEP 2009 

Novel Engineered Ion Channel Provides Controllable Ion Permeability for Polyelectrolyte Microcapsules Coated with a Lipid Membrane Author(s): BATTLE, AR; VALENZUELA, SM; MECHLER, A; et al. Source: ADVANCED FUNCTIONAL MATERIALS Volume: 19 Issue: 2 Pages: 201-208 Published: JAN 23 2009 

Organization of Cytochrome P450 Enzymes Involved in Sex Steroid Synthesis PROTEIN-PROTEIN INTERACTIONS IN LIPID MEMBRANES Author(s): PRAPORSKI, S; NG, SM; NGUYEN, AD; et al. Source: JOURNAL OF BIOLOGICAL CHEMISTRY Volume: 284 Issue: 48 Pages: 33224-33232 Published: NOV 27 2009 

Structure and homogeneity of pseudo-physiological phospholipid bilayers and their deposition characteristics on carboxylic acid terminated self-assembled monolayers Author(s): MECHLER, A; PRAPORSKI, S; PIANTAVIGNA, S; et al. Source: BIOMATERIALS Volume: 30 Issue: 4 Pages: 682-689 Published: FEB 2009 

For older publications please see my

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Chemistry of biomembranes Membranes are the physical boundaries of cells and sub-cellular structures, preserving cell integrity while also serving as a platform for life functions related to metabolism, sensing and intercellular communication. Phospholipids, organised into a two-dimensional bilayer surface, provide the primary material for the membrane structure, incorporating functional proteins: transmembrane channels that enable controlled passage of chemicals; receptors; and functional enzymes that perform tasks related to e. g. respiration and photosynthesis. While in its native complexity a cell membrane is composed of a range of phospho- and glycolipids, cholesterol, cytoskeletal (e. g. actin) fibres, in practice, protein function and activity depends only, or mainly, on the phospholipid components and cholesterol. We study the formation and physicochemical properties of phospholipid bilayers of various composition, with microscopic and microspectroscopic methods. Our aim is to describe the structural and chemical characteristics of cell membranes that are deterministic of protein function and activity. We create artificial "biomimetic" membranes on arbitrary surfaces to mimic the physiological environment of living cells, for applications such as the biocompatible coating of implants or autonomous microscopic surgical tools, and the development of biosensing and biocatalytic methods by using membranes as in-vitro platform for redox enzyme and/or ionchannel activity.

Antimicrobial peptides Disruption of the integrity of cellular membranes underpins a broad spectrum of biophysical processes throughout the biological realm. Pore formation by perforin-like proteins in bacteria and protozoan pathogens play a pivotal role in microbial egress and virulence. The neurodegenerative effects of the Aβ peptide, the causative agent in Alzheimer’s disease, is postulated to derive from the formation of cation-sensitive ion channels in the neuronal membranes. The process of programmed cell death, or apoptosis, is contingent on the assembly of the pro-apoptotic proteins Bak or Bax in the outer mitochondrial membrane into pores, allowing the contents of the inner-membrane space to escape. Antimicrobial proteins that provide innate immunity against pathogens in most complex organisms, e.g. defensins, disrupt the cytoplasmic membrane of pathogens, facilitate the efflux of essential ions, and thereby disrupt ionic homeostasis. In spite of the variety of roles this apparently simple process plays in nature, the mechanism of membrane disruption is not fully understood.  We study the molecular mechanism of peptide-membrane interaction. The focus is on identifying the factors contributing to the specificity and selectivity of these peptides towards pathogenic membranes. To achieve this goal, we study the role of lipid composition, peptide sequence, the physiological environment and temperature at various stages of the interaction, and the role these factors play in switching between disruptive and non-disruptive interaction pathways. Collaboration with Dr Brian Smith, Dr Peter Barnard, Dr Mark Hulett (LIMS) and Prof. Mibel Aguilar (Monash).Membranes are the physical boundaries of cells and sub-cellular structures, preserving cell integrity while also serving as a platform for life functions related to metabolism, sensing and intercellular communication. Phospholipids, organised into a two-dimensional bilayer surface, provide the primary material for the membrane structure, incorporating functional proteins: transmembrane channels that enable controlled passage of chemicals; receptors; and functional enzymes that perform tasks related to e. g. respiration and photosynthesis.

While in its native complexity a cell membrane is composed of a range of phospho- and glycolipids, cholesterol, cytoskeletal (e. g. actin) fibres, in practice, protein function and activity depends only, or mainly, on the phospholipid components and cholesterol. We study the formation and physicochemical properties of phospholipid bilayers of various composition, with microscopic and microspectroscopic methods. Our aim is to describe the structural and chemical characteristics of cell membranes that are deterministic of protein function and activity. We create artificial "biomimetic" membranes on arbitrary surfaces to mimic the physiological environment of living cells, for applications such as the biocompatible coating of implants or autonomous microscopic surgical tools, and the development of biosensing and biocatalytic methods by using membranes as in-vitro platform for redox enzyme and/or ionchannel activity.

Molecular self-assembly and surface chemistry Second order interactions play a role in most, if not all, molecular processes, including solvation, chemical reactions and the formation of supramolecular host-guest systems, as well as protein folding and fibrillogenezis. These interactions, and the processes they determine, are the main interest of the field of surface chemistry. We focus on the study of the molecular mechanism of, and the role of environmental factors in, surfactant self-assembly into micelles and lamellar structures, with an emphasis on phospholipid membranes, as well as fibrillogenezis of short "designer" peptides (collaboration with Prof. Patrick Perlmutter, Monash) and wild type proteins.

Biophysical methods Our research relies on a biophysical tool base. The centerpiece is high resolution atomic force microscopy which is capable of imaging interacting molecules under physiological conditions. We also actively develop this method, aiming at improving resolution and enhancing imaging speed. For the study of interactions we use quartz crystal microbalance that can measure nanogram mass changes, such as a protein-protein interaction on a surface; ellipsometry for nm thickness measurements; differential scanning calorimetry to measure binding and phase transition enthalpies; and fluorescent microscopy with a capability of in-house synthesis and bioconjugation of unique metal complex labels (collaboration with Dr Peter Barnard).