Efficient wastewater treatment monitoring is vital for addressing water scarcity. Microbial fuel cells (MFCs) have emerged as real-time biosensors for biochemical oxygen demand (BOD) in urban wastewater. Discrepancies in signal generation may arise due to changes in the composition and metabolism of mixed-culture electroactive biofilms stemming from different wastewater compositions. In this study, 3D-printed MFC-based biosensors were employed to assess the BOD of sterile complex artificial wastewater and untreated urban wastewater. Alterations in the microbial composition of the anode were evaluated using 16S rRNA sequencing and metagenomics analysis. Results show that MFC-based biosensors can be effectively recalibrated for diverse types of wastewater, maintaining consistent sensitivity (0.64 ± 0.10 mA L mg⁻¹ m⁻² with synthetic wastewater and 0.78 ± 0.13 mA L mg⁻¹ m⁻² with urban wastewater) and limit of detection (49 ± 8 mg L⁻¹ for synthetic wastewater and 44 ± 7 mg L⁻¹ for urban wastewater). Crucially, pre-sterilization, conductivity adjustments, and nitrogen purging of wastewater are not required before its introduction into the biosensor. However, the presence of native aerobic microorganisms in the wastewater might affect the current output. Metagenomics and taxonomic analyses revealed that the alterations in biofilm composition are predominantly in response to the varied chemical and microbiological compositions of different substrates. Despite variations in anodic biofilm composition, the MFC-based biosensor maintains a relative error comparable to the standard BOD test. This highlights the resilience and flexibility of the biosensor when directly used with a variety of wastewater types before full biofilm adjustment.

有效的废水处理监测对于解决水资源短缺问题至关重要。微生物燃料电池（MFC）已成为城市废水中生化需氧量（BOD）的实时生物传感器。由于不同废水成分产生的混合培养电活性生物膜的成分和代谢发生变化，可能会出现信号产生的差异。在这项研究中，采用 3D 打印的基于 MFC 的生物传感器来评估无菌复杂人工废水和未经处理的城市废水的 BOD。使用 16S rRNA 测序和宏基因组分析评估阳极微生物组成的变化。结果表明，基于 MFC 的生物传感器可以针对不同类型的废水进行有效的重新校准，并保持一致的灵敏度（合成废水为 0.64 ± 0.10 mA L mg ⁻¹ m ⁻² 和 0.78 ± 0.13 mA L mg ⁻¹ m ⁻² （城市废水）和检测限（合成废水为 49 ± 8 mg L ⁻¹ ，检测限为 44 ± 7 mg L ⁻¹ 城市废水）。至关重要的是，在将废水引入生物传感器之前，不需要对废水进行预灭菌、电导率调整和氮气吹扫。然而，废水中存在的原生需氧微生物可能会影响电流输出。宏基因组学和分类学分析表明，生物膜组成的变化主要是对不同基质的不同化学和微生物组成的反应。尽管阳极生物膜成分存在差异，基于 MFC 的生物传感器仍保持与标准 BOD 测试相当的相对误差。 这凸显了生物传感器在完全生物膜调整之前直接用于各种废水类型时的弹性和灵活性。