When most scientists think of antimony, they probably think in terms of ‘that toxic metalloid’. For me, that’s not the case; for me, antimony is an element of surprising medical relevance.
I was first tasked in my early studies with antimony’s more popular older sibling, bismuth, but after many trials and many lacklustre experiments I came upon some research into antimony as a medicinal complex. I was intrigued by this research; I had always thought antimony to be the big bad toxic element of group 15, along with the closely related arsenic (turns out oxidation state really matters here!). After synthesis and characterisation, I compared these antimony compounds to my bismuth analogues and was pleasantly surprised to find them not only more selective in their biological activity, but inherently more stable too. I was confused; everything I had previously thought about group 15 was turned upside down: bismuth is not always the ‘green’ ‘non-toxic’ metal I thought it was – no, bismuth in this case was a cold hard killer! Antimony, however, exhibited excellent selectivity, solubility and stability, three major constituents of an effective antimicrobial. Not only was it the inherently better choice in my biological research, it also produced the most beautiful, yet simple, crystal structures, something as an inorganic chemist I was ecstatic to obtain.
The more I delved into the world of antimonials, the more I found out about the misunderstood medicinal. Antimony has been used medically for many years; it constitutes the front-line treatment for one of the most neglected, yet somewhat unheard of, tropical diseases on our planet, that being leishmania. Sure, these treatments aren’t as easily obtained as pepto-bismol, and their side-effects do range from mild to severe, but they are the most efficient and cost-effective treatments we have to control this devastating illness. My research has turned to focus then on synthesising antimonials that have less severe toxic effects, with increased stability and lipophilicity.
I love what I do, and I love the elements I use. Antimony complexes are a joy to make and characterise, and when they exhibit selectivity activity to the parasite it becomes a bonus, it feels as if this element is worth more than what popular media would portray it to be. To me, antimony is a misjudged element, hidden in the shadow of the more popular bismuth. Antimony is the unsung hero of group 15; antimony is my element.