From Passive Monitoring to Active Control: Aggregation-induced Emission-driven Antimicrobial Nanotechnology for Long-duration Spaceflight

Abstract

Humanity has entered a new phase of space exploration in which long-term orbital habitats are becoming routine. Within these permanently inhabited, hermetically sealed modules, microbial safety has emerged as a pivotal determinant of crew health and mission reliability. Closed circulation of air and water, together with the altered physiology and virulence of microorganisms in micro-gravity, renders conventional, Earth-based control measures insufficient and calls for space-specific innovations. Against this backdrop, China's rapid progress in astronautics, exemplified by the successful assembly and sustained operation of the Tiangong Space Station, has become a powerful catalyst for the development of next-generation microbial monitoring and abatement technologies.

To tackle this challenge, a landmark research programme has been initiated, which is supported by the “Space Station Program Technology Demonstration Experiments” initiative and led by Professors Yulin Deng and Ying Zhang from Beijing Institute of Technology. A central component is the “aggregation-induced emission (AIE)-armed bionic nanostructure module,” a cutting-edge integrated system that merges multidisciplinary expertise. Its key subsystems are the product of collaboration among three leading teams: AIE fluorophores, developed by Academician Ben Zhong Tang's group at The Chinese University of Hong Kong (Shenzhen); Bionic nanostructures, engineered by Professors Zuowan Zhou and Xiaoling Xu at Southwest Jiaotong University; The intelligent antimicrobial control logic was developed by the engineering team led by Mr. Qihuan Xiong at Changsha XiangJi-Hiden Technology Co., Ltd.and Dr. Chunhua Yang at Beijing Genxin Technology Co., Ltd.

This innovative module achieves a critical breakthrough: it simultaneously enables real-time microbial imaging and active pathogen eradication, thus addressing the dual challenge of rapid detection and effective suppression of microorganisms in the space environment.

Launched at 05:34 CST on 15 July 2025 from the Wenchang Space Launch Center, the Tianzhou-9 cargo spacecraft delivered the first batch of in-orbit experimental materials for this microbial monitoring and protection project. Beyond its immediate technical goals, this mission symbolises China's strategic commitment to solving the fundamental biosafety challenges of long-duration space habitation through convergent, state-of-the-art technological solutions—paving the way for safer, more sustainable human presence in orbit and beyond.

Although the space environment is inherently inimical to most terrestrial microorganisms, complete sterility aboard orbiting platforms remains unattainable. Contaminants accompany every launch vehicle, propagate via crew activities, and are introduced through experimental payloads, thereby establishing complex microbial consortia within the closed ecological loops of a space station. Once established, these communities give rise to three interrelated hazards (Figure 1). First, the formation of resilient biofilms accelerates material degradation and bio-corrosion, threatening the integrity of air-handling ducts, water-recovery assemblies, and load-bearing structures [1, 2]. Second, biofouling within fluid circuits progressively occludes filters and pipework, increasing hydraulic resistance and jeopardising the reliability of life-support subsystems [2]. Third, chronic exposure to biofilm-associated pathogens and their metabolic toxins undermines crew immunocompetence and elevates the incidence of opportunistic infection [2, 3]. Mitigating these risks demands an integrated control paradigm that couples high-efficacy sterilisation with continuous bio-surveillance and rapid, in-situ remediation.

To satisfy stringent planetary-protection requirements, guarantee crew health and preserve the performance of on-board hardware, contemporary space programmes employ a suite of physical, chemical, and surface-engineering strategies for microbial control (Table 1).

The Tianzhou-9 mission carries an AIE-armed bionic nanostructure module expressly conceived to meet the stringent demands of microbial surveillance and mitigation in the space-station environment. Developed under the leadership of Academician Ben Zhong Tang, the platform exploits the team's pioneering AIE technology, which affords real-time, in-situ visualization of microbial populations while simultaneously enabling rapid bactericidal intervention. In partnership with Southwest Jiaotong University, the researchers have embedded AIE luminogens within a biomimetic antimicrobial nanostructure capable of triggering on-demand sterilization during flight. Under microgravity conditions, the module rigorously evaluates the efficacy of diverse physical, chemical, and hybrid sterilization mechanisms, delivering quantitative data with high sensitivity, swift response, operational simplicity, and long-term stability. Its successful deployment establishes a robust microbiological safety barrier for extended crewed missions and, by validating this advanced technology in orbit, promises to accelerate terrestrial applications in clinical infection control, industrial hygiene, and public health (Figure 2).

The integration of AIE technology with bionic nanostructures represents a transformative advancement in microbial management for long-duration spaceflight. The AIE-armed bionic nanostructure module, deployed aboard the Tianzhou-9 cargo spacecraft, successfully bridges critical gaps in current space station microbial control strategies by enabling: 1. Real-Time Pathogen Monitoring: AIE luminogens provide high-sensitivity, photostable fluorescence imaging for in-situ detection of microbial proliferation and biofilm formation, overcoming the limitations of traditional passive monitoring. 2. Active, Resistance-Free Sterilization: The synergistic combination of AIE-driven photodynamic action and biomimetic nanostructures achieves rapid, adaptive pathogen eradication without inducing microbial resistance—a key drawback of chemical disinfectants. 3. Enhanced Mission Safety: By simultaneously addressing microbial detection and elimination, the module significantly mitigates risks to crew health (e.g., opportunistic infections) and hardware integrity (e.g., bio-corrosion) in confined space environments.

This paradigm shift—from reactive to proactive microbial control—has been validated under microgravity conditions during the Tianzhou-9 mission, demonstrating unparalleled operational robustness and long-term stability. The technology's success not only fortifies biosafety protocols for China's space station but also pioneers scalable solutions for terrestrial challenges in clinical hygiene, water purification, and industrial biofilm management.

The authors declare no conflicts of interest.