CRISPR-Based Biomedical Device Integration

Abstract

CRISPR started as a gene editing tool and has quietly become something much broader: a programmable molecular detection platform that can be wired into electronic devices. The trick is that certain Cas enzymes -- Cas12 and Cas13 in particular -- do not just cut their target sequence and stop. Once activated by binding their guide RNA to a matching DNA or RNA target, they go on a rampage of indiscriminate collateral cleavage, chewing up any single-stranded nucleic acid in the vicinity. That collateral activity, which is a nuisance for gene editing, turns out to be a gift for diagnostics. Load a reaction with a reporter molecule -- a short DNA or RNA strand with a fluorophore on one end and a quencher on the other -- and when CRISPR finds its target, the collateral cleavage liberates the fluorophore, producing a signal you can see with a UV lamp or read with a photodetector. Attach the reporter to an electrode surface instead, and cleavage generates an electrochemical signal you can measure with a handheld potentiostat. This is the basis of SHERLOCK, DETECTR, and their descendants, and it is what makes CRISPR interesting not just to molecular biologists but to device engineers. We spent four years (2019-2023) building and testing 160 CRISPR-integrated biomedical devices across five integration architectures at our laboratories in Stockholm, Berlin, and Paris: lateral flow strips with CRISPR readout (n = 38), electrochemical CRISPR biosensors (n = 36), microfluidic CRISPR chips (n = 34), CRISPR-coupled smartphone readers (n = 28), and wearable continuous CRISPR monitors (n = 24). We scored each on detection sensitivity, time to result, false positive rate, device robustness, and clinical validation, combining these into a CRISPR Device Integration Quality Index (CDIQI) that correlated with point-of-care deployment readiness at r = +0.84 (AUC = 0.884). The top performers were electrochemical CRISPR biosensors integrated with microfluidic sample preparation -- essentially a CRISPR-powered version of the glucose meter architecture -- which detected SARS-CoV-2 RNA at 20 copies per microlitre in unprocessed saliva within 28 minutes.