Self-Stretchable Fiber Liquid Sensors Made with Bacterial Cellulose/Carbon Nanotubes for Smart Diapers

Abstract

Liquid sensors for detecting water and body fluids are crucial in daily water usage and health monitoring, but it is challenging to combine sensing performance with high tensile deformation and multifunctional applications. Here, a substrate-free, self-stretchable bacterial cellulose (BC)/carbon nanotube (CNT) helical fiber liquid sensor was prepared by the solution spinning and coiling process using BC as the water-sensitive matrix and CNTs as the active sensing materials. The BC/CNT (BCT) fiber sensor has a high stretch ratio of more than 1000% and a rapid response for a current change rate of 104% within 1 s, which is almost unaffected under washing and various stretching or knotting deformations. By combination of the BCT fiber, we can design smart diapers or water level detectors, which rapidly monitor the status of smart diapers or water level, and the monitoring result can be transferred on time through an alarm device or smartphone. In short, the scalable and continuous preparation of the self-stretchable BCT helical fiber will provide a capacious platform for the development of a wearable sensor applied in daily life (such as smart diapers, water level detection, etc.)

Carbon-based electrochemical biosensors as diagnostic platforms for connected decentralized healthcare

“…View Article Online performance. Designed sensor provided a sensitivity of 240 µA/mM.cm -2 with the LOD of 148 µM as shown (Figure 8B) 95 .Modification of bacterial cellulose with CNTs provides flexibility and smart stretch-resistant for self-wearable platforms as recently demonstrated with a water sensor for smart diapers (Figure 8C) 96 .Handling of fluid in an ePAD design is very important for accurate measurements. A hydrophobic barrier was drawn by pattering (photolithography, wax printing, inject printing, stamping, screen printing etc.)…”

“…Carbon-based nanostructures, particular CNTs and graphene, can be deposited on flexible platforms such as fabric, paper, or skin-conformable tattoos. They can be used in conjunction with other materials such as fibers of bacterial nanocellulose 96 , ZnS 87 , or AuNPs 88 and be interfaced with biomolecules to create multifunctional hybrid films. These multicomponent structures are relatively complex and their fabrication on an industrial scale is still challenging.…”

“…8C). 96 Handling of fluid in an ePAD design is very important for accurate measurements. A hydrophobic barrier was drawn by pattering (photolithography, wax printing, inject printing, stamping, screen printing etc. )…”

Research on Dynamic Urine Volume Detection System Based on Smart Flexible Textile Sensors

“…Liang et al [18] proposed a self-stretching BCT spiral fiber prepared through dry-wet spinning and winding processes, with BC as the water sensing substrate and carbon nanotubes as the active sensing material. Due to the scalable and continuous preparation process as well as the design of the spiral structure, optical fiber sensors were combined with diapers and scales (scale wires) to create smart diapers and intelligent water level detectors.…”

A novel multi-scale pressure sensing hydrogel for monitoring the physiological signals of long-term bedridden patients

“…3 Diapers have become a necessity for long-term bedridden patients because of their convenience. 4,5 During the use of diapers, the neglect of replacing diapers in a timely manner can lead to skin diseases or infections, but frequent diaper checks can cause embarrassment for patients and caregivers, which greatly reduce the quality of life for patients. 6,7 Therefore, in order to prevent the secondary damage of UI to patients and improve their lives, it has become an urgent problem to develop an advanced sensor to monitor when patients need to have their diapers replaced.…”