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Single-molecule protein studies are challenging because both single-molecule sensitivity and a high dynamic range are needed to comprehensively analyze the complex mixture of proteins present in biologically relevant samples. One way to achieve both high sensitivity and dynamic range would be to create a protein array that arranges single molecules with uniform spacing to achieve billions of well-separated molecules on a patterned surface. So far, no approach has combined both a uniformly patterned surface and the possibility to deposit a single protein at each spot. In addition, current patterning approaches cannot be scaled to the size needed to interrogate billions of molecules. Here, we present a scalable method for fabricating dense protein arrays using brushy-DNA origami deposition onto patterned surfaces. Brushy-origami structures are made large enough to occupy the features on the array singly and we developed an efficient process to ensure single protein conjugation to the brushy-origami structures. We hypothesize that our technology will ultimately enable the development of highly scalable proteomics platforms that address the need for both single-molecule sensitivity and high dynamic range.

Next Generation Sequencing (NGS) technologies have revolutionized basic biological and clinical research, especially in oncology. NGS cancer assays are used to determine cancer predisposition, identify tumor mutations, monitor treatment response and develop personalized therapies. Here, GenapSys presents a scalable, low cost, and high accuracy sequencing platform based on electrical impedance detection. We demonstrate that a single run with a 16M sensor chip generates up to 2 Gb of data, with greater than 99% raw accuracy and an average read length of about 150 bp. We highlight its applications for oncology research, using diverse cancer panels on reference and clinical samples. We tested hybrid-capture and multiplex PCR-based cancer panels on a range of DNA sources, including oncology reference standards derived from cell line DNA, cfDNA standards, as well as clinical samples: FFPE, fresh frozen tumor tissue, and blood. For hybrid-capture libraries, we used the IDT xGen Pan Cancer 1.5 and Exome Research panels. We detected low frequency mutations in the range of 1%-24.5% across multiple reference standards with the cancer panel, and observed high correlation in allele frequency with expected values (R2 > 0.99). Similar results were obtained with an amplicon panel, the Ion AmpliSeq Cancer Hotspot Panel v2. Whole exome sequencing and pan cancer sequencing of clinical FFPE, fresh frozen and blood samples showed high concordance (F1-score > 95%) of SNV mutation calling with commonly used NGS technology. Thus, we demonstrate that the GenapSys Sequencing Platform is an accurate, scalable, and low cost solution for oncology research on a wide range of sample types and NGS assays. Citation Format: Saurabh Paliwal, Mohammad Fallahi, Ali Nabi, Tyson A. Clark, Bin Dong, Srijeeta Bagchi, Maryam Jouzi, Hannah Ritchie, Lydia Bonar, Anthony Thomas, Narin Tangprasertchai, Meysam R. Barmi, Xavier Gomes, Subra Sankar, Hesaam Esfandyarpour. Oncology research applications on an electrical impedance based, high accuracy sequencing platform [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-315.