A turn-on fluorescent aptasensor for Pb2+ detection based on rhodamine B dye leakage from the internal cavity of hollow gold nanoparticles

• Published in: Food chemistry 2025-01, Vol.463 (Pt 4), p.141440, Article 141440
• Main Authors: Hassibian, Sepideh, Esmaelpourfarkhani, Masoomeh, Abnous, Khalil, Amin, Mahsa, Ghazvinian, Fatemeh, Alibolandi, Mona, Ramezani, Mohammad, Nameghi, Morteza Alinezhad, Mollasalehi, Hamidreza, Farrokhi, Naser, Dehnavi, Seyed Mohsen, Taghdisi, Seyed Mohammad
• Format: Article
• Language: English
• Subjects: affordability; aptasensors; blood serum; chitosan; detection limit; fluorescence; Fluorescent aptasensor; fluorescent dyes; food chemistry; Hollow gold nanoparticles; humans; Label free aptamer; lead; Lead ion; low fat milk; mineral water; nanocarriers; nanogold; oligonucleotides; Rhodamine B; rhodamines
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2024.141440

In this project, a sensitive fluorescent aptasensor was fabricated to detect lead ions (Pb2+) by applying hollow gold nanoparticles (HGNPs) as a nano-carrier and rhodamine B (RDB) fluorescent dye as the signal agent. In the aptasensor that was created, the specific attachment of the aptamers to Pb2+ ions led to the release of aptamer from the chitosan (CTS) coated-HGNPs loaded with RDB, causing an increase in fluorescence intensity due to the leakage of RDB. The method demonstrated specific detection of the target analyte, achieving a detection limit (LOD) of 1 ppb and a broad linear dynamic range spanning from 2 to 1000 ppb. The aptasensor was able to accurately measure the concentration of Pb2+ in human serum, low-fat milk, and mineral water samples. The suggested biosensor, which offers the benefits of simplicity, user-friendliness, affordability, and high sensitivity, is well-suited for use with complex samples such as environmental and clinical samples. [Display omitted] •A fluorescent aptasensor was developed to detect Pb2+ ions by applying HGNPs and RDB.•HGNPs with a high capacity for RDB loading and RDB as the signal indicator.•The designed HGNPs-based fluorescent aptasensor exhibited a detection limit of 1 ppb.•The aptasensing method demonstrated specific detection of the target analyte.•The sensor was able to accurately measure the concentration of Pb2+ in milk samples.