App Notes Archives | Quantum-Si

Optimizing Immunoprecipitation Workflows for Next-gen Protein Sequencing

Proteins play a vital role in virtually all biological processes, serving as key regulators of cellular functions, disease biomarkers, and therapeutic targets. However, the identification, isolation, and characterization of proteins from biological specimens can be challenging due to their complexity and diversity. Next-Generation Protein Sequencing (NGPS) on Platinum® offers a groundbreaking approach to deeply interrogate individual proteins with high resolution on a user-friendly benchtop platform. When combined with protein separation or enrichment methods, Platinum enables characterization of individual proteins from biological samples, revealing crucial details such as amino acid variants and PTMs. In this application note, we demonstrate a method that combines Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) protein separation and NGPS on Platinum to identify and characterize serum proteins. This method holds potential for applications beyond serum, offering new insights into disease mechanisms and advancing therapeutic and diagnostic developments.

Next-Gen Protein Sequencing Enables Accurate AAV Serotype Profiling and Mixture Resolution for Gene Therapy

Characterization of Serum Proteins by Coupling Protein Separation Techniques with Next-Gen Protein Sequencing on Platinum®

Immunoprecipitation of IL-6 from Human Serum for Next-Gen Protein Sequencing on Platinum®

The enrichment of low-abundant proteins from complex biological matrices is a key step for many proteomic workflows. In this technical note, we present an immunoprecipitation protocol compatible with Quantum-Si’s next-gen protein sequencing workflow. This process utilizes an on-bead digestion protocol that forgoes the sample elution step and proceeds directly to the preparation of digested peptide […]

Identifying Monoclonal Antibodies with Quantum-Si’s Next-Generation Protein Sequencing Technology

Identifying low-abundance monoclonal antibodies in a population of polyclonal antibodies can provide critical insights for diverse applications such as understanding disease mechanisms, disease diagnostics, vaccine development, therapeutic antibody discovery, and serological surveillance. Existing methodologies, despite their utility, come with significant disadvantages including high costs, complex procedures, and time-intensive workflows, which often limit their broad application. […]

Comparison of Protein Sequencing Analysis of CDNF, IL6, and FGF2 on Platinum® and Mass Spectrometry

Mass Spectrometry has been the gold standard for deciphering information about a protein’s amino acid sequence. However, mass spectrometry is not convenient and accessible to everyday scientists with its large capital equipment expense and advanced expertise requirement. Scientists often need to resort to using core facilities to sequence proteins. Furthermore, mass spectrometry infers amino acids […]

Sequencing and Identification of Proteins from Five-protein Mixtures on Platinum®

Complex biological samples contain a diverse array of proteins, and understanding their presence and relative abundance is vital for unraveling the underlying biological processes related to human health and disease. However, traditional protein detection methods requiring antibodies or targeted reagents often face limitations in identifying proteins with variant peptide sequences. Quantum-Si’s Platinum® instrument provides an […]

Quantum-Si’s Next Generation Protein Sequencing Technology Enables Rapid and Accurate Distinction of Variants of the SARS-CoV-2 Virus

Accurate and rapid identification of SARS-CoV-2 variants is crucial for effective surveillance and disease monitoring. Furthermore, patients with long COVID may still have residual spike protein in their blood. Distinguishing variants in long COVID patients via protein sequencing could lead to new understandings and treatment of the disease. In this application note, we present a method […]