Adrian V George, Senior Lecturer

School of Chemistry, Building F11

University of Sydney, NSW 2006, Australia

Email address: george@chem.usyd.edu.au

Telephone: +61 (2) 9351-4413

Fax: +61 (2) 9351-3329

Career Profile:

Areas of Interest:

Research Projects:

Organometallic Chemistry

The project aim is to use the porphyrinogen and calixpyrrole structure as a ligand for metals engaged in catalysis reactions.   By providing a cavity for the metal we intend to extend the lifetime of the catalyst and have the ability to modify the reactivity of the metal through a variety of interactions with the calixpyrrole host.  Large radii lanthanoid metals, such as samarium, have been coordinated in the cavity.   Syntheses of a range of these cavity materials has been developed.

Detection of steroid use in sports

 

Dehydroepiandrosterone (DHEA), a naturally produced androgen, may be administered by athletes with the aim of increasing levels of the more active androgens such as testosterone (T) and dihydrotestosterone (DHT). The International Olympic Committee (IOC) prohibits DHEA administration in athletes, however its detection remains difficult due to an incomplete understanding of DHEA metabolism as well as inter-individual variations.

 

In this study, Gas Chromatography-Mass Spectrometry (GC-MS) demonstrated that a single oral administration of DHEA (100 mg) to a subject altered the urinary steroid concentrations of androsterone (A) and etiocholanolone (Et). The ratio of the concentration of A to Et (A/Et) may provide a screening marker of DHEA administration. Values of A/Et less than 0.5, measured following DHEA administration, were compared to a reference distribution of A/Et values obtained from 858 urine samples. Only 3 of these had A/Et values less than 0.5.

 

The urine samples collected after DHEA administration were also analysed by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS) to determine the Carbon Isotope Ratio (CIR, d13C) of A and Et. This technique demonstrated that d13C A and d13C Et were reduced following the single administration of DHEA. The difference between d13C Et and d13C A increased from 1.6 ‰ at the time of administration to a maximum value of 5.2 ‰, which corresponded to a minimum A/Et value of 0.4.

 

Multiple oral administrations of 100 mg DHEA, morning and night for seven days to a separate subject resulted in Et being 13C depleted in relation to the DHEA that was administered. Also, an unknown compound, detected in many of the GC-C-IRMS traces was shown to have d13C values similar to those of Et. This compound, identified as 3a-5-cyclo-5a-androstan-6b-ol-17-one, may prove to be an effective indicator of DHEA administration.


Education in Chemistry

Detailed analysis, both qualitative and quantitative, of examination scripts from some first year chemistry units has been undertaken.  When combined with qualitative data from students about their experiences and perceptions, a number of interesting questions can be addressed.  Firstly, the question of the extent to which the outcomes from our current assessment system are a reflection of students’ understanding can be examined.  Analysis of students’ approaches to examination questions provides information about both misconceptions held and overall motivations and goals (performance orientation versus mastery orientation).  Such information can be used not only to improve teaching in areas of student difficulty, but can also inform curriculum design more generally, with the ultimate goal of promoting deeper student understanding of the material under study. Secondly, the analysis provides data that supports the common belief that organic chemistry is an area that some students simply ‘don’t get’.  The existence of barriers to deeper understanding of organic chemistry has been proven, and the nature of these barriers examined.  Such information has obvious implications for improving teaching and learning in this fundamental area of chemistry, although more work in this area is needed. 

Selected Publications

Book: 

& "The Essentials of Organic Chemistry"

George, A.V.; Field, L.D.; Hambley, T.W.; 1996 Prentice Hall

Papers:

 

Nyholm 2000 lecture - Photons, Fireflies and a Feeling for Colour

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