Letters: April 2016

Academic drug hunters

The recent article Drugs don’t grow on trees felt uncharacteristically dated, and does not recognise the profound changes in academic drug discovery that have taken place over the past few years.

Big pharma has, of course, long been the main source of new drugs on the market (not all of which are novel). However, the continuing contraction of its research base, not least in the chemical sciences, has created new opportunities that many academic institutions have been keen to exploit, and a diverse range of models have been established to do just this. Most of these initiatives have deliberately recruited ex-industry scientists, who have added a crucial layer of robust drug discovery and development professionalism to hitherto largely academic activities. None of this comes cheaply, but programmes such as the Wellcome Trust’s seeding drug discovery scheme have made funding available.

The article is right in saying that relatively few drugs that are currently in the clinic are outcomes of academic discovery. This is not surprising given the scale of resources historically assigned to this area, although those that have made it have often been game changers. These include pregabalin, discovered by Rick Silverman; emtricitabine, discovered by Dennis Liotta; and abiraterone, discovered at the Institute of Cancer Research, UK. Abiraterone has ushered in a revolution in the treatment of advanced prostate cancer and its discovery and development is a textbook example of what academic drug discovery is capable of achieving.

Let’s hope that the adventure of drug hunting, which has generated real enthusiasm in significant numbers of the academic chemistry community, will not only produce winners from time to time, but also lead to a reduction in the cost of new drugs and help educate politicians about the importance of science. As the pharma industry knows only too well, success does not come easily.  

Stephen Neidle FRSC

UCL School of Pharmacy, UK

Practical lessons

I read the recent article on the safety of experiments during chemistry education with dismay. Once again a writer has resorted to anecdotal evidence of what happened ‘when I was at school’ or ‘I know someone who…’ to replace known facts.

The article concludes that the requirement for practical competence in chemistry education ‘has been almost entirely eliminated’ and states children are ‘forbidden to do “dangerous” chemical experiments’. This is incorrect. In no way are children forbidden to carry out chemical experiments in UK schools, and practical competence is precisely what A-level teachers will now be required to assess.

This is not to deny that there are problems with chemistry education in the UK. A recent foray into controlled assessment showed what occurs when examination boards try to tailor-make a practical with a contrived investigation in a short space of time; thankfully, this is now changing to a teacher assessment of practical skills. In addition, the UK still needs more chemistry graduates to become teachers.

Organisations such as Cleapss, the school practical science and technology advisory service, or the Scottish Schools Education Research Centre (SSERC) are in place to assist teachers and technicians in our schools in delivering high-quality practical work. No doubt both will continue to respond to the thousands of phone calls every year from teachers and technicians wishing to carry out practical chemistry safely in their departments.

Bob Worley FRSC

London, UK

On the day that I read of parents’ concern about a demonstration involving the use of a few drops of benzene in a test tube, I learned of a recent study into air pollution. Is the danger greater when working in a laboratory where hazards are understood and managed, or walking to the bus stop?

I came to fully understand chemistry through my practical lessons at college and during my career, which started working at the laboratory bench. Fortunately, young people are still drawn to the subject, if only as a stepping stone to the biosciences. What can be done about the perception, often based on sensational journalism, that all things chemical are dangerous?

John Meakin CChem MRSC

Tonbridge, UK

An education evolution

Philip Moseley bemoans a decline in graduates’ grasp of basic chemistry. It’s easy to sympathise, though I suspect each generation decries the shortcomings of youth and it’s easy to forget from a position of experience just how little we knew when we were young. However, his comments need to be understood in context. 

I did my BSc in the 1960s, Philip’s ‘good old days’. Education was highly selective and only about 6% entered university. A-level syllabuses were dictated by universities and university entrance was competitive. There were large numbers of (often rather tedious) lectures and much of our time was spent in laboratory work. This was all supported by an implied contract that success would be rewarded with well-paid employment. The chemical industry was thriving and big companies actively competed to recruit graduates.

The situation today is completely different. Around 47% of 18-year-olds enter university, and science students have many more course options. There are far more chemistry departments, which now compete for students. Long hours of laboratory work are no longer possible even if universities could resource them. The discipline has expanded, and topics which were specialist material in the 1960s are now routinely taught in first year classes. Perhaps most importantly, outside the pharmaceutical sector the large industrial research labs are all long gone. The progression from BSc to PhD to industrial research or academia is no longer guaranteed.

I believe that our students are now better educated than I was, and that universities do a good job in preparing students for the world they will have to live in. Students see themselves as customers and can no longer be ignored by staff more interested in research. For the serious, the MChem allows first-hand experience of research before committing to it, and industrial placement is common for students who wish it. Projects, report writing, problem solving, and poster and oral presentations are all parts of the curriculum and a good memory can no longer guarantee a good degree.

While I have sympathy for Philip’s solutions, I think that a shift to the more ‘professional degrees’ he wishes would require a return to a long-gone era – and might well result in an undesirable drop in student numbers, and in the number of chemistry graduates entering other professions.

Norman Billingham MRSC

Brighton, UK

Monster mash

I consider myself an adventurous cook, having used gellan gum to make both beads for immobilising antibodies for research and strawberry ‘caviar’ for a dessert. I therefore had to try The Hot Plate’s recipe for sweet root vegetable purée using enzymes.

I use diastatic malt powder regularly in making bread to break down the wheat starch into food for the yeast, but had not tried it in other foods. Thus I decided to experiment with mashed potatoes for dinner one night. My wife, insisting on a control, removed some of the mashed potatoes before I added the enzyme. I used only about 0.5% malt powder by weight, did not bother to heat my experiment – just left the potatoes in the pan – and waited only 20 minutes for the enzyme to do its work (I was too hungry to wait longer).

My wife agreed that the potatoes were smoother and not gummy, but I think she was being generous of the watery mess that was there as we went to eat! The potatoes were definitely sweeter than the control, but I think the enzyme broke down far too much of the starch to still be considered a potato purée. I write simply to caution other readers that the type of potato and amount of malt powder to use will take some experimentation; don’t try this recipe out on guests before making it a few times yourself.

I can’t wait to use what I learned about tempering chocolate in my next batch of truffles, and I ask that you keep the articles on food chemistry coming. My kitchen is just another scientific laboratory waiting for experiments.

Jerome Ferrance MRSC

Charlottesville, USA

Response from Editor: We’re glad you’re enjoying the series. We try out all the recipes ourselves with our resident expert Yuandi Li – some with more success than others. We had a similar experience with malt powder and potato; we found it was much more effective with sweet potato instead. You can follow our progress (including our recent marshmallow disaster) here. 

A significant problem

The article on Sers was informative and interesting. However, the detection limits quoted for melamine and glyphosate are not presented in accordance with current practice. 

The limit of detection is invariably defined as a 95% probability of detection when the analyte is actually present (a 5% probability of a false negative). The value of a detection limit for melamine of 0.126ppm implies, through the three significant figures given, an uncertainty of +/– 0.001ppm, hence a true detection limit of 0.003 +/– 0.002ppm. Both detection limits quoted (for melamine and glyphosate) suffer from an excess of significant figures and no clearly stated uncertainty, which does not allow the merit of the values to be judged. If the minimum detected levels had been quoted as, for example, 0.13 +/– 0.8 for melamine and 0.84 +/– 0.58 for glyphosate, a much more informative indication of the capability of the technique would have been given.

Robert Crafts CChem MRSC

Newtown, UK

Thomas Grimley

Thomas Grimley, who died aged 93 in January 2016, was widely regarded as the father of theoretical surface science. He made major contributions to our understanding of chemisorption and catalysis, which in turn lead to the modern age of computational chemistry. 

After his PhD at the University of Bristol (his supervisor was Nobel prize winner Nevill Mott), Grimley moved to Liverpool University, where he remained throughout his career. His pioneering papers on chemisorption provided seminal results and ideas, including the role of itinerant electrons and of electronic resonant and discrete states in the surface bond; the notion of an embedded cluster; and the need for a self-consistent approach and the innovative use of the field theory in adsorption. His work had an enormous influence on surface science, and his opinion was held in great esteem around the world.

I began working with Grimley as a post-doctoral fellow in 1974, studying non-adiabatic processes in chemisorption. Our collaboration continued after he retired; he never stopped working and spent time on scientific problems every day until his death. 

Everyone will remember Grimley as an extremely bright scientist. He could model a scientific problem quickly and come to an approximate solution containing the essential effects. He also fully appreciated the importance of computation, wrote his own codes and supervised the numerical work of his postdocs. Grimley liked a rather secluded life devoted to study and thinking, and his honesty and integrity were exemplary. He shaped my scientific career by emphasising dedication to studies and critical assessment of one’s results. 

I will miss this great scientist.

Gian Paolo Brivio

Università di Milano-Bicocca, Italy