Detection of Pancreatic Cancer miRNA with Biocompatible Nitrogen-Doped Graphene Quantum Dots

Early-stage pancreatic cancer remains challenging to detect, leading to a poor five-year patient survival rate. This obstacle necessitates the development of early detection approaches based on novel technologies and materials. In this work, the presence of a specific pancreatic cancer-derived miRNA (pre-miR-132) is detected using the fluorescence properties of biocompatible nitrogen-doped graphene quantum dots (NGQDs) synthesized using a bottom-up approach from a single glucosamine precursor. The sensor platform is comprised of slightly positively charged (1.14 +/- 0.36 mV) NGQDs bound via pi - pi stacking and/or electrostatic interactions to the negatively charged (-22.4 +/- 6.00 mV) bait ssDNA; together, they form a complex with a 20 nm average size. The NGQDs' fluorescence distinguishes specific single-stranded DNA sequences due to bait-target complementarity, discriminating them from random control sequences with sensitivity in the micromolar range. Furthermore, this targetability can also detect the stem and loop portions of pre-miR-132, adding to the practicality of the biosensor. This non-invasive approach allows cancer-specific miRNA detection to facilitate early diagnosis of various forms of cancer.

Automated summary

This study developed a non-invasive method for early detection of pancreatic cancer by detecting specific miRNA using fluorescence properties. Biocompatible nitrogen-doped graphene quantum dots (NGQDs) were synthesized and combined with charged bait DNA to form a complex. The fluorescence of NGQDs can distinguish specific DNA sequences with high sensitivity. This approach enables the detection of cancer-specific miRNA non-invasively, facilitating early diagnosis.