“…Unlike former methods that use deterministic barcoding (Liu et al, 2020; Salmen et al, 2018; Stahl et al, 2016) or split-pool bead techniques (Rodriques et al, 2019; Stickels et al, 2020; Vickovic et al, 2019), our technique is based on the solid-phase amplification of a random barcode molecule, which can be conveniently achieved by the Illumina sequencing-by-synthesis (SBS) platform (Bentley et al, 2008). We show that this technology enables the generation of up to 1.5 million different spatially defined barcodes in a 1 mm 2 area, which is substantially higher than any currently existing technologies by several orders of magnitude (e.g., ~10,000 fold over VISIUM (Bergenstrahle et al, 2020), ~600 fold over DBiT-seq (Liu et al, 2020), ~120 fold over Slide-Seq (Rodriques et al, 2019; Stickels et al, 2020) and ~15 fold over HDST (Vickovic et al, 2019)). Seq-Scope has a center-to-center resolution of 0.5-1 μm, far superior to previous technologies and comparable to an optical microscope.…”