3D-Printed CRISPR-based detection system powered by a reusable handwarmer

Nucleic acid-based molecular diagnostics are essential for the prevention, early detection, and treatment of cancer and infectious diseases. In this study, we developed a 3D-printed, electricity-free detection system for CRISPR-based nucleic acid detection. To eliminate the need for costly electrical heaters, we developed a reusable heating platform powered by a sodium acetate-based handwarmer. To maintain optimal temperatures for the CRISPR reaction, we designed and fabricated a 3D-printed heatsink filled with docosane wax to regulate the temperature. The fully 3D-printed microfluidic chip integrates finger-activated fluid transport via a 3D-printed flexible blister, a CRISPR reaction chamber, and a lateral flow strip for visual readout. We demonstrated the system's analytical performance by detecting HPV-16 DNA with a sensitivity as low as 1 femtomolar. Additionally, we validated its clinical pilot feasibility using clinical cervical samples, achieving results consistent with standard PCR assays. Overall, this low-cost, reusable, and electricity-free detection system offers a practical solution for point-of-care molecular testing, particularly in resource-limited settings.