 In summary, we developed a novel SERS substrate based on CU2O microcubes combined with AGNPs. The CU2O AG5 nanocomposite exhibited the best SERS performance with the limit of detection as low as 1nm and the enhancement factor as high as 4x108. This work provides a new approach for developing SERS substrates with enhanced sensitivity and selectivity for trace levels MO in water solvent. This article was authored by Thay Thu Ha Pham, Shen Howei Thu, Nuyen DACDN, and others.