Highly selective optical sensor N/S-doped carbon quantum dots (CQDs) for the assessment of human chorionic gonadotropin β-hCG in the serum of breast and prostate cancer patients

A low-cost, accurate, and highly selective method was used for the assessment of the human chorionic gonadotropin β-hCG in the serum of breast and prostate cancer patients. This method is based on enhancing the intensity of luminescence displayed by the optical sensor N/S-doped carbon dots (CQDs) upon adding different concentrations of β-hCG. The luminescent optical sensor was synthesized and characterized through absorption and emission and is tailored to present blue luminescence at λ(em) = 345 nm and λ(ex) = 288 nm at pH 7.8 in DMSO. The enhancement of the luminescence intensity of the N/S-doped CQDs, especially, the characteristic band at λ(em) = 345 nm, is typically used for determining β-hCG in different serum samples. The dynamic range is 1.35–22.95 mU mL(−1), and the limit of detection (LOD) and quantitation limit of detection (LOQ) are 0.235 and 0.670 mU mL(−1), respectively. This method was practical, simple, and relatively free from interference effect. It was successfully applied to measure PCT in the samples of human serum, and from this method, we can assess some biomarkers of cancer-related diseases in human body.