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for how they stepped into the breach in 2002 with strong backing when, in the immediate aftermath of 9/11, he was struggling to get HPLC 2002 in Montreal off the ground. The focus of Wainer’s actual talk was on his most recent work in CMAC and the possibilities that it opened up. He tracked back to the origins of this form of molecular biochromatography to the point where he was at a “fork in the road” and decided to follow a previously untrodden track rather than to continue his earlier work on chiral separations. He charted his path down the CMAC track, recounting the work of collaborators, post- docs and PhD students such as Per Lundahl, Krzysztof Jozwiak, Ruin Moaddell, Sharvil Patel and Prateek Bhatia as he progressed from nicotinic choline receptors on immobilised artificial membrane (IAM) phases to the study of transporter proteins using capillary columns to the discovery of nuclear efflux proteins and currently to the study of mitochondria. The next speaker in the session was John Lough from the UK. Lough emphasised the importance of honouring Wainer’s pioneering work in the early days of the field of separations by commercial chiral stationary phases. Also he pointed out its contemporary significance in terms of ‘chiral switch’ patent court cases and attempted to show how, even in these days of hyper-proliferation of commercial CSP, Wainer’s classification into Types I-V was still applicable. Jozwiak’s lecture was primarily a medicinal chemistry presentation, around RR- and SS-fenoterol but this served the purpose of illustrating how an initial interest in CMAC could lead to a useful medicinal study. Carlo Bertucci addressed, “Role in Drug Discovery and Development: Circular dichroism detection system” pointing out, for example, how it could readily be used with achiral separation systems. The session was rounded off by Ruin Moadell who, like Wainer, works for the US government at the National Institute of Aging (NIA), Baltimore. As heir apparent to Wainer at the National Institute of Aging (NIA), Moaddell was able to bring the molecular biochromatography / bioaffinity chromatography story right up to date. He introduced his topic by rationalising the development of


Wainer’s work from chiral separations on α1-acid glycoprotein (AGP) (over a quarter a century ago) through chymotrypsin CSP work, study of allosteric interactions on human serum albumin (HAS) to CMAC and recent work on tobacco smoke condensates going into creating pharmacophores, epigenetics, the nucleosome and sitains. The most recent work involves the use of protein-coated magnetic beads using the sirtuin6 enzyme C-terminal domain to which potentially anti-aging compounds in medicinal plant extracts might bind.


At one point in the week a speaker remarked that “UHPLC is now behind us”. Also, in his abstract Michael Dong (Genentech) had suggested that “many practitioners now believe that the transformation from HPLC to UHPLC as the standard platform is already complete”. However, one wouldn’t have thought that UHPLC was something of the past from the interest evident from the attendance at Dong’s own “Best Practice of Ultra-High-Pressure LC (UHPLC) in Pharmaceutical Analysis” session on the Tuesday afternoon. Dong himself and Davy Guillarme (University of Geneva) shone the spotlight on pharmaceutical applications. Dong described work on senna, a prostate cancer NCE with three chiral centres and related substances determination for a multi-api (active pharmaceutical ingredient) product. Guillarme covered a very wide range of applications, touching upon SFC and HILIC by UHPLC. For chiral work, in the absence of sub-2 µm CSP, he used chiral


derivatisation to resolve 7 enantiomeric pairs in 3 minutes on an achiral phase. The next talk by Michael Frank (Agilent, Waldbron) was very informative as he talked openly without a hint of a sales pitch of the compromises that had to be made in designing a UHPLC system for a wide market. He talked of the prioritisation of precision, accuracy and HPLC transferability. He discussed detection issues and the problems that might be caused at low wavelength if mobile phase component mixing is not sufficiently thorough. Sometimes the compromise must be on resolution but Agilent now offer an ultra-low dispersion kit to adapt some existing instruments. Normally audience numbers would fall off slightly as 17.00 approached. However, here, there was a discernible expectation in the air as audience numbers began to swell. The final speaker was Jim Jorgenson who was about to pontificate on “Future Trends in UHPLC”. He began in positive fashion. Referring to the sterile debate between UHPLC or core-shell particles, he urged, “Why not, let’s do both.” (Perhaps a nod of approval here towards Phenomenex and


their 1.3 µm core-shell particles.)While drawing from his own work he graciously praised the good work of others, in particular, the use of non-porous particles by Mary Rogers. Much smaller particles are


needed to deal with the peak capacity problem. 0.47 µm particles had been used and had produced much lower back pressures than anticipated because of ‘slip flow’ (arising from the surface not being easily wetted; some similarities to ‘plug flow’ in CE). He also covered the high pressures that would be needed to obtain high throughput with high efficiency, HILIC (emphasising how critical the dissolution solvent was), modern SFC (UPC2), on-column detection for reducing extra-column dispersion, monoliths (1 x 106 plates but in a 16 h run time, so higher pressures needed) and open-tubular columns. Last but not least, he re-visited CE. It had “gone underground” but would again increase in importance with the greater need for protein separations.


The Wednesday pm session on 2D-LC was another that was very well attended. There was a discernible shift here. With an acceptance that, with the difficulty in identifying stationary phases that were truly orthogonal, it was not often possible to spread analytes in a complex mixture right across the two-dimensional space. Therefore there was an emphasis on practical aspects and 2D-LC was being put to very real applications. Herman Cortes (“retired from Corporate America”!, University of Tasmania) felt that there was still a need for more resolution and stated that, in this respect, the use of temperature had been overlooked and that the use of ‘heat pulses’ could be useful. In the case of Kelly Zhang (Genentech)


Pittcon Hall of Fame, here featuring Bruker NMR pioneer, Gunther Laukien


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