Acetylated Distarch Phosphate-Mediated Tough and Conductive Hydrogel for Antibacterial Wearable Sensors

Abstract

Conductive, stretchable, and flexible hydrogel wearable sensors have attracted extensive attention in the fields of artificial intelligence and electronic equipment. However, it is an enormous challenge to fabricate conductive hydrogel sensors with biocompatibility, antibacterial properties, and toughness. Here, a highly conductive hydrogel with excellent toughness, good biocompatibility, and strong antibacterial properties was prepared by incorporating acetylated distarch phosphate (ADSP) into poly(vinyl alcohol) (PVA)/polyhexamethylene biguanide hydrochloride (PHMG). The addition of ADSP not only ionized sodium ions to make the hydrogel conductive but also provided abundant hydroxyl groups to form hydrogen bonds with PVA to improve the toughness of the hydrogel. Furthermore, PHMG endowed the hydrogel with antibacterial properties toward E. coli (Escherichia coli, Gram-negative bacteria) and S. aureus (Staphylococcus aureus, Gram-positive bacteria). Meanwhile, the hydrogel was implanted in mice for 14 days, and the surrounding tissue remained in good condition. More importantly, the hydrogel could detect ECG signals and electrical signals under different actions. This study affords a novel approach for exploiting wearable sensors with antibacterial properties and biocompatibility.

Recent progress of antibacterial hydrogels in wound dressings

“…Moreover, in vivo antibacterial experiments demonstrated that the hydrogel could effectively kill S. aureus in the wound (>97.1%). In addition to ionic liquids, there are some significant developments in antibacterial hydrogel based on novel synthetic materials such as N -halamine compounds [ 137 ], quaternary ammonium compounds [ 138 ], imidazole derivatives [ 139 ], biguanides [ 140 ], phenols [ 141 ], nitriles [ 116 ] et al. For example, positively charged quaternary ammonium salts can bind to negatively charged bacterial cell walls, then disrupt the bacterial structure.…”

Synthesis of a Low Metal-Corrosive and High-Antibacterial Effective Guanidine Salt Oligomer via Ion Exchange

“…Furthermore, they are safe for humans and animals. In particular, their excellent heat resistance renders them widely useful in the field of plastic antibacterial modification. − Recently, polypentamethylene guanidine hydrochloride (PPMG), which is synthesized from biobased pentamethylene diamine, has attracted significant attention as a green antibacterial agent. , However, similar to the use of ordinary guanidine salts, the long-term use of this antibacterial agent corrodes the processing equipment, specifically at high temperatures . During the normal corrosion process, a passivation film is formed on the metal surface, which changes the state of the metal from active to passive, thus improving its corrosion resistance. , When active halogen ions come into contact with metal surfaces due to their small size, they diffuse easily into the metal passivation films and increase the ionic conductivity.…”

Stretchable Organohydrogel with Adhesion, Self-Healing, and Environment-Tolerance for Wearable Strain Sensors

“…The overlap of wearable healthcare applications and flexible electronic engineering is guiding the development direction of functional soft materials , and device design integration. , Recently, hydrogel-based wearable sensors with high hydration, tunable functionality, and high sensitivity have shone in fields such as medical devices, − human–machine interfaces, − and flexible electrodes. − For example, Fu et al developed a super-stretchable conductive hydrogel based on triple crosslinking for sensitive monitoring of human physiological motions . Nevertheless, due to the lack of adhesion properties, the conventional hydrogel-based strain sensor required additional assistance to achieve close contact between the sensor and the substrate during usage, which largely impair the accuracy and durability of signal detection. − Meanwhile, these hydrogels were easily damaged during the complex and continuous movement of the human body, which limited their application especially in human health care monitoring.…”