I’ll echo and expand a little on what
@artful_lounger and
@PQ have already mentioned... It is not uncommon for those interested in both the arts and the sciences to gravitate towards architecture, but the extent to which a degree in architecture is scientific or artistic in nature varies from programme to programme, and it’s actually a somewhat misleading reputation (architecture is neither an art, nor a science - debate me).
There are options, both at undergraduate and postgraduate that might interest you. Not least of all because there’s a big debate going on (and has been for some time now) about the future of architecture and the role of the architect. Increasingly you’ll find institutions discussing interdisciplinary and trans-disciplinary learning and teaching; indeed, the Dean of the Bartlett mentioned to me a couple weeks ago that “this is where all the interesting stuff is happening”.
With all that said, here are two options you might like to consider (both of which it would be trivial for you to switch to, assuming your application to the Bartlett has been successful)...
UCL’s Architecture and Interdisciplinary Studies (K101/K102): think of this more of a “creative plus something” degree. The beauty of this programme (and it’s cousin, the BASc (Hons) in Arts and Sciences, also taught at UCL) is that, assuming you meet the pre- and co-requisites, you’re able to elect open modules from anywhere else within UCL. It is a very broad degree, almost completely tailor-able to your interests, designed to teach “architectural thinking” and for you to apply such thinking to your individual area of interest, but... it is emphatically
not an architecture degree. And I would think most on the programme do so for the opportunity to study additional social sciences, rather than hard sciences (though nothing is stopping you from doing so).
Or...
UCL’s Engineering and Architectural Design (KH11): predominantly focused on engineering and built environment physics, the intention is for this to meet the educational criteria for Chartered Engineer status and as such opens up routes into allied engineering and science professions and postgraduate study. It’s also intended to offer ARB-accreditation, such that it’ll allow its graduates to follow either or both careers. It likely attracts those interested in facade design or the design of unusual structural elements, as well as those with an interest in pursuing UCL’s B-Pro non-accredited architecture masters.
You could conceivably make a case to study a materials science masters following either of the above programmes, but you’d need to demonstrate (not inconsiderable) self-directed study in chemistry and chemical engineering, and it would by no means be guaranteed. (There will undoubtedly be some who’ve studied chemistry or a related science at masters without having done so at undergraduate level, but these will be few and far between, and will be special cases for which it would be hard to advise how to replicate their experiences.)
There is a lot of interesting stuff going on at the intersection of biology and chemistry, and architecture and engineering at the moment; check out UCL’s own MArch/MSc in Bio-integrated Design, and also Newcastle and Northumbria’s newly launched Hub for Biotechnology in the Built Environment. It is predominantly being researched from a materials perspective, with the architects involved still trying to work out how to make use of the new technologies, but the fact is biochemistry/synthetic biology is becoming increasingly important in the built environment, so your interests are not unusual any more (if they ever were).
I have to agree with what has already been mentioned: if you know now that it is unlikely you’ll want to become a registered, practicing architect, then think very carefully about your next move... but I’d also like to make it clear that you can change careers. If you make a “mistake” now, there are ways of fixing it later (I speak from considerable experience in this regard).
Good luck, and if I can offer any further help, don’t hesitate to ask. I am and have been in a very similar situation.