A tailored ratiometric fluorescent sensor based on CdTe and MgF₂ quantum dots for trace N-ethylpentylone detection

The development of low-cost and highly sensitive ratiometric fluorescence sensor, CdTe@MIPs/MgF₂, for N-Ethylpentylone (NEP) detection in wastewater samples is described. In this system, CdTe@MIPs (λex = 370, λem = 570) are employed as the receptor and response unit for NEP, with MgF₂ (λex = 370, λem = 470) as the reference signal to enhance stability. Under optimal conditions, the sensor shows fluorescent quenching response at 570 nm to NEP in linear range of 2–200 nM, with LOD of 0.6 nM. The sensor also demonstrates significant selectivity for NEP over other analogues and interferents, making it ideal for practical applications in wastewater analysis. This approach is potentially more cost-effective and sensitive than conventional mass spectrometry in detecting abused substances in sewage. Additionally, the MgF₂ fluorescent nano-material was first-ever developed and investigated, which may be significant in future research.