Graphene-Based Steganographic Aptasensor for Information Computing and Monitoring Toxins of Biofilm in Food

Abstract

Fungi-forming biofilm would produce various toxins in food. The toxin contamination will cause great harm to food and human health. Herein, a novel graphene-based steganographic aptasensor was assembled for multifunctional applications, which depended on the specific recognition and information encoding ability of DNA aptamers [mycotoxins, including zearalenone (ZEN) and ochratoxin A (OTA) aptamers, as models] and the selective absorption and fluorescence quenching capacities of graphene oxide (GO). The graphene-based steganographic aptasensor can be regarded as an information encryption and steganographic system using GO as a cover, aptamers for specific target recognition as information carriers and dual targets (ZEN and OTA) as special keys. In our work, the fluorescence of capture probes (Cy3 aptamer and Alexa Fluor 488 aptamer) was quenched by GO to realize information encryption. In the presence of dual targets in the GO-APT solution, Cy3 aptamer (APT1), and Alexa Fluor 488 aptamer (APT2) were released from the surface of GO, decrypting the hidden information. In addition, our work offers a sensor for rapid and sensitive simultaneous fluorescence determination of ZEN and OTA. The detection limit of the aptasensor was 1.797 ng/ml for ZEN and 1.484 ng/ml for OTA. In addition, the graphene-based steganographic aptasensor can be used to construct a molecular logic gate system in which GO, aptamers, and mycotoxins are employed as the input and compounds and fluorescence signals were used as the output. This would be helpful to control the biofilm toxin in the future.

Prevalence and Therapies of Antibiotic-Resistance in Staphylococcus aureus

“…In the medical field, nanoparticles enhance the ability to deliver a drugin the human body (Li et al, 2010). After several layers of nanoparticle-encapsulated smart drugs enter the human body, they can actively search for and attack cancer cells or repair damaged tissues (Wang et al, 2020). China has successfully developed a new generation of nanoscale antibacterial drugs.…”

Metagenomic Next-Generation Sequencing Improves Diagnosis of Osteoarticular Infections From Abscess Specimens: A Multicenter Retrospective Study

“…Additionally, the remaining data were further mapped against the RefSeq Microbial Genome Database of viruses, bacteria, fungi, and parasites created and maintained by the National Center of Biotechnology Information 2 . RefSeq analysis yielded 1,798 whole genome sequences matching those of DNA virus taxa, 6,350 bacterial genomes or scaffolds, 1,064 pathogenic fungi of human infections, and 234 parasites associated with human diseases (Wang et al, 2019). Reporting criteria for infectious pathogens identified by mNGS included: (i) >30% relative abundance at the genus level in bacteria or fungi; (ii) at least three unique reads from a single viral, bacterial, or fungal species; (iii) at least one unique read matching M. tuberculosis complex (MTBC) species (Wang et al, 2019).…”

“…RefSeq analysis yielded 1,798 whole genome sequences matching those of DNA virus taxa, 6,350 bacterial genomes or scaffolds, 1,064 pathogenic fungi of human infections, and 234 parasites associated with human diseases (Wang et al, 2019). Reporting criteria for infectious pathogens identified by mNGS included: (i) >30% relative abundance at the genus level in bacteria or fungi; (ii) at least three unique reads from a single viral, bacterial, or fungal species; (iii) at least one unique read matching M. tuberculosis complex (MTBC) species (Wang et al, 2019). If more than one pathogen was detected, the species present in greatest relative abundance yielding the highest number of unique reads was deemed the probable species associated with osteoarticular infection in that patient.…”

Progress on Structured Biosensors for Monitoring Aflatoxin B1 From Biofilms: A Review

“…When the target analytes are added, the fluorophore-modified aptamer would release from the quencher surface due to the binding affinity of the aptamer and target being stronger than that of the aptamer and quencher, and the aptamer would subsequently combine with the targets and yield a significant fluorescence intensity. In addition, metal nanoparticles, humic acid (HA) (Guo M. et al, 2019), graphene oxide (GO) (Wang et al, 2020), and a quenching group have frequently been used as fluorescence quenchers.…”