Piezoelectric Polymers in 3D Printed Flexible Biomedical Sensors-Advances, Processing Strategies, and Future Directions

The integration of piezoelectric polymers and additive manufacturing has contributed to the growth of biomedical sensing by creating a flexible, lightweight, and individualized technology. Of these, polyvinylidene fluoride (PVDF), copolymer of the latter, PVDF-TrFE, and the composite based on nanofillers are especially good in terms of their high-quality electromechanical response, biocompatibility, and flexibility of mechanics. These polymers can be shaped into complex geometries, multizonal patches, and conformal systems that can be comfortably integrated with implants, skin, or organs when paired with 3D printing. The sensors developed as a result of this partnership have the capability of real-time monitoring of temperature, pressure, motion, respiration, and other physiological indicators. The paper critically analyses the recent developments in piezoelectric polymers, 3D printable flexible sensor development, which has found applications in biomedical engineering. A comparative analysis of the printing method, such as fused deposition modeling, direct ink writing, inkjet, electrohydrodynamic, and PolyJet printing, is given after analyzing the significant materials and the relationship between the processing structure and properties of the printed materials. Sensor architectures such as multilayer stacks, interdigitated electrodes, multizonal arrays, and biomimetic designs that maximize device sensitivity and adaptability are highlighted. Skin-interfaced patches, prosthetic feedback systems, respiratory monitors, motion and gait sensors, electronic skin, and implantable devices are among the biomedical applications that are investigated. Finally, prospects in self-powered biosensors, machine learning-assisted design, and multifunctional integration are explored, along with issues about polymer crystallinity control, scalability, long-term biocompatibility, and clinical translation. When considered as a whole, these developments underscore the revolutionary potential of 3D-printed piezoelectric polymers in precision medicine and next-generation personalized healthcare.