QSI ▲ +2.7% - Quantum-Si incorporated $QSI - Quantum-Si Announces Detection of 18 Amino Acids Using a Developmental Sequencing Kit on Proteus™ Quantum-Si shares rose 2.7% following the company's announcement that its developmental sequencing kit successfully detected 18 amino acids using its Proteus platform, a step forward in its proteomics technology capabilities. 15-SEP-2026 07:00 AM ET