Liquid glues can be messy and frustrating, especially when dealing with soft and squishy materials like tissues or engineered organs. While there are glues for almost any situation, they are not always suitable for these materials. One alternative is 3D-printing, which fuses structures together without the need for glue, but this can be time-consuming and require specialized equipment.
Another option is electroadhesion, which uses an electric field to attach oppositely charged materials. This technique can form chemical or physical connections between materials, and can be achieved using only a household battery and pencil lead. Researchers have previously demonstrated electroadhesion to hold gels to tissues, but now they have shown that it can work for any two materials with opposite charges, providing a precise and reversible way to bond them together.
In their investigation, the researchers utilized a gel and three kinds of capsules made from naturally occurring polymers, alginate or chitosan, that had opposite charges. By attaching the materials to graphite electrodes and exposing them to a 10-V electric field for roughly 10 seconds, the oppositely charged components became stuck together. This bond was durable enough to withstand gravity and could last for years.
The team was able to create chains and 3D cubes from single, spherical capsules through electroadhesion. Furthermore, the researchers used the technique to sort capsules by charge, employing a charged gel or a finger “robot” to adhere the capsules together. This research highlights the versatility of electroadhesion and its potential for use in areas such as robotics and tissue engineering.
Source: American Chemical Society