Flexible MoS2-Based Wearable SERS Sensor for Noninvasive Early Diagnosis of Glutaric Acidemia

Section snippets

Materials

High purity molybdenum foil (0.03 mm × 100 mm × 100 mm Mo (≥99.999%)), glutaric acid (analytical standard, 99.2%), cetyltrimethylammonium bromide (CTAB, 99% biotech grade), methyl blue (MB), rhodamine 6G ( ≥ 99%) were purchased from Shanghai McLean Biochemical Technology Co., Ltd. Thiourea ( ≥ 99%), acetone (AR, analytically pure), artificial urine, H₂SO₄ ,and absolute ethanol ( ≥ 99.5%) were purchased from Aladdin (Shanghai) Biochemical Technology Inc. Distilled water (Millipore Milli-Q grade)

Optimized Synthesis of MoS2 Nanoflowers via H⁺ dosage Tuning

Figure 1 displays SEM images of MoS₂ substrate. As shown in Fig. 1a, without the addition of H₂SO₄. MoS₂ initially grows as nanosheets on the molybdenum foil surface. Upon adjusting the H⁺ concentration, specifically by adding 0.1 mL of H₂SO₄ (Fig. 1b), uniform MoS₂ nanoflowers form on the nanosheets. By varying the amount of H₂SO₄ added, we obtained MoS₂ substrate with distinct morphologies (Supplementary Information Fig. S1a). The experimental results demonstrate that the amount of H₂SO₄

Conclusion

In summary, we successfully synthesized a highly sensitive, flexible MoS₂ substrate using a simple hydrothermal method. This flexible substrate can be integrated into baby diapers to collect infant urine, enabling non-invasive detection via SERS technology. The flexible MoS₂ substrate demonstrates a detection limit (LOD) for biomarkers as low as 3.29 nM and EF up to 8.36×10⁶, with high uniformity and experimental reproducibility. We employed this substrate to detect glutaric acid in artificial

CRediT authorship contribution statement

Yingzhou Huang: Conceptualization, Formal analysis, Funding acquisition, Supervision, Writing – review & editing. Zhaoxian Chen: Data curation, Formal analysis. Xuliang Xia: Conceptualization, Data curation, Formal analysis, Project administration, Writing – review & editing. Qi Liu: Data curation, Formal analysis, Investigation, Writing – original draft. Yuqin Xie: Data curation, Formal analysis. Wenrou Yu: Data curation, Formal analysis, Investigation. Luo Ren: Conceptualization, Formal

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Data availability

Data will be made available on request.

Declaration of Competing Interest

☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This research was supported by National Natural Science Foundation of China (12374342), Natural Science Foundation Project of CQ CSTC (CSTB2025NSCQ-GPX0768) and Sharing Fund of Chongqing University’s Large-scale Equipment.