A highly elastic, moisturizing, and adhesion conductive hydrogel designed for cuffless blood pressure measurement

Real-time monitoring of blood pressure in athletes during exercise is of great importance, however, conventional methods pose challenges in achieving portable and instantaneous measurements. While, the electrodes used in emerging wearable blood pressure monitoring instruments still have certain defects. In this study, a novel cuffless blood pressure monitoring system was developed using a self-developed polyacrylamide/trehalose/LiCl (PAM/Trehalose/LiCl) conductive hydrogel as the electrode material. The hydrogel electrode has high tensile (strain: 3568 %) and conductive properties (7.57 S/m), while also exhibiting low toughness, moisture retention, and adhesion. While ensuring the comfort of the monitoring system, it can also accurately detect strain over a wide range of deformations (GF value of up to 6.31 in the strain interval of 2000–3400 %). Finally, this system accurately extracts relevant features of PPG and ECG signals and predicts cuff-less blood pressure using the BP Transformer-XL model. The main control chip, ECG detection module, Bluetooth module, and PPG detection module are integrated, and band-pass filtering and data feature extraction techniques are combined. The study found that the average errors in systolic and diastolic readings were 2.09 mmHg and 1.57 mmHg, respectively, compared to those measured by an electronic sphygmomanometer. Therefore, this study successfully combined hydrogel electrodes with a cuffless blood pressure monitoring system to provide technical support for the development of personalized training programs for future athletes and the guarantee of long-term competitive performance. •Achieving the integration of conductive hydrogels with electronic devices and biological tissues.•Cuffless blood pressure monitoring system based on hydrogel.•A multifunctional hydrogel electrode catering to diverse performance requirements.•Advanced signal processing achieves precise blood pressure prediction.