Simultaneous detection of dual food adulterants using graphene oxide and gold nanoparticle based surface enhanced Raman scattering duplex DNA biosensor

• Main Authors: Khalil, Ibrahim, Yehye, Wageeh Abdulhadi, Julkapli, Nurhidayatullaili Muhd, Ibn Sina, Abu Ali, Chowdhury, Faisal Islam, Khandaker, Mayeen Uddin, Hsiao, Vincent K. S., Basirun, Wan Jefrey
• Format: Article
• Published: Elsevier 2021
• Subjects: QC Physics; QD Chemistry; T Technology (General)
• Online Access: http://eprints.um.edu.my/34099/

Development of a facile, fast, sensitive and multiplex DNA detection for the quantitative verification of food adulterant is of high significance these days. RT-PCR, and nanoparticle based fluorescence and electrochemical detection techniques have been successfully used in clinical medicine. However, requirements of preconditioning steps and fluorescence dye labeling in RT-PCR, inherent photobleaching and overlapping spectra of fluorescent probe in fluorescent assay, are the few drawbacks that urge to find a suitable alternative. Surface-enhanced Raman scattering (SERS) provides molecule specific fingerprint spectra, could be a strategic to resolve the limitations. Here, we report a SERS based duplex DNA detection strategy for simultaneous and quantitative detection of a meat adulterant (pork) and an endangered species - Malayan Box Turtle (MBT). In the biosensing strategy, SERS active dual platforms - graphene oxide-gold nanoparticles (GO-AuNPs) and AuNPs, and uniquely designed Raman tag intercalated short-length signal probe (SP) sequences are used. The sensing principle relies on the covalent linking of SP sequences functionalized AuNPs and capture probe (CP) functionalized GO-AuNPs via hybridization with corresponding target DNA. Coupling of multi-component platforms contributes in huge SERS signal enhancement due to electromagnetic and charge transfer mechanism. The biosensor showed an improved sensitivity in simultaneous detection of both adulterants with limit of detection (LOD) is 1 x 10(-14) M. Moreover, efficiency of SERS biosensor was validated by the DNA extracted from real samples with a LOD of 1 x 10(-13) M. Furthermore, the biosensing approach showed excellent sequence specificity in discriminating DNA sequences of five non-target species and specificity towards single nucleotide differentiation.