Circularly polarized luminescence as a contingency assay for 'mirror life' bio-hazards

Mirror life presents a low-likelihood but high-severity global biosecurity threat that has attracted the attention of bioscientists, governments and international security organizations. However, current analytical techniques are not fit to identify mirror life biohazards. Herein, we propose the first assay method for screening against mirror life. This approach is based upon optical circularly polarized luminesce (CPL) signatures generated by fluorescent probes, which bind to subcellular targets (e.g. membranes, organelles, nucleic acids, etc.). Probes can either be achiral or be intrinsically chiral. We set out why a multi-probe reporter panel approach incorporating many CPL-generating probes is necessary to identify mirror life with a high degree of confidence (i.e. avoiding false positives). The distinct CPL signatures can be analysed via recent innovations in CPL detection, i.e. rapid CPL spectroscopy, CPL microscopy (enantioselective differential chiral contrast, EDCC, imaging) and CPL EDCC cameras. While these are advanced technologies, they share the same fundamental optical principles as three-dimensional cinema glasses and so are amenable to scaling and portable applications. The CPL assay approach to mirror life screening could be a useful tool for screening against mirror life biohazards and ensuring compliance with any potential future international legislation against mirror-life research.