Wet-spinning of fluorescent fibers based on gold nanoclusters-loaded alginate for sensing of heavy metal ions and anti-counterfeiting

Fluorescent and robust fibers based on gold nanoclusters-loaded alginate were successfully prepared by wet spinning of gold nanoclusters and alginate. The relationship between process conditions, mechanical properties, and fluorescent properties of fibers was investigated. The as-prepared fibers exhibited high mechanical strength (up to 7.09 cN/dtex) and remarkable red emission under ultraviolet excitation. The fibers could be used as a simple, low-cost, and high-selectivity fluorescent sensor for detecting Cu²⁺ and Hg²⁺ among various metal ions in aqueous solution, with a detection limit as low as 187.99 nM for Cu²⁺ and 82.14 nM for Hg²⁺, respectively. Furthermore, the novel fluorescent fibers were used as an anti-counterfeiting label through knitting into textile materials. The wet-spun functional fibers may be applied to the design of smart wearable sensors and flexible optical sensors.