Disinfecting Waste Medical Masks Turned into Valuable Carbon Dots for Detection

A recent study from Zhengzhou University in China revealed that it is possible to disinfect waste medical masks and re-use them by converting them into a valuable material for detecting harmful substances (1). Published in the journal Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, the study describes how a hydrothermal method was used to convert waste medical masks into blue emissive carbon dots (CDs), which are a type of carbon nanomaterial (1).

The Covid-19 pandemic led to widespread usage of disposable medical masks. Because of the overabundance of these products in the market, the amount of discarded masks have accumulated over the past couple years and found their way into the environment, some of which may still carry harmful viruses. In addition to posing a threat to the environment and human health, the discarding of medical masks is also a waste of resources. However, the researchers found that the masks could be effectively disinfected while simultaneously transformed into something useful by subjecting the waste masks to a high-temperature hydrothermal treatment (1).

The mask-derived CDs (m-CDs) were found to have blue-emissive fluorescence, making them suitable for use as fluorescent probes for detecting harmful substances, such as sodium hydrosulfite (Na₂S₂O₄) and Fe³⁺(1). The compound Na₂S₂O₄ is widely used in the food and textile industries; however, can be seriously harmful to human health, whereas Fe³⁺ is harmful to both the environment and human health because of its widespread usage in various industries (1).

The hydrothermal method that was used in this study possessed several key advantages over other methods that are capable of converting waste medical masks into carbon dots. First, it is a simple and low-energy process that does not result in environmental pollution (1). Second, and perhaps most importantly, the resulting m-CDs have valuable applications in detecting harmful substances, making them a useful material that can be created from waste (1).

In summary, the researchers hope that their findings will encourage further investigation into the potential uses of waste medical masks as a resource for creating valuable materials (1). They also hope that this study sheds light on how vital it is that humans adhere to medical waste disposal best practices, which will in turn help prevent environmental contamination and protect public health (1).

Reference

(1) Li, S.; Hu, J.; Aryee, A. A.; Sun, Y.; Li, Z. Three birds, one stone: Disinfecting and turning waste medical masks into valuable carbon dots for sodium hydrosulfite and Fe3+ detection enabled by a simple hydrothermal treatment. Spectrochim. Acta A 2023, 296, 122659. DOI: 10.1016/j.saa.2023.122659