Identifying Exogenous DNA in Liquid Foods by Gold Nanoparticles: Potential Applications in Traceability

Abstract

Quality control of food products requires the development of powerful analytical tools and regulations to avoid fraud to consumers and ineffective product recalls. DNA barcoding represents a potential strategy for application in food traceability, which involves the use of exogeneous short DNA oligonucleotides (DNA markers) for tracing the origin of food, such as suppliers, producers, attributes, and points of distribution. However, it is generally considered that exogeneous DNA molecules are strongly shielded by complicated interactions with intrinsic ingredients and easily degraded in complex food systems. This consideration leads to the lack of analytical methods to readily identify DNA markers in food, thereby preventing one from exploiting the barcoding capability of DNA markers in food. In this work, we explored the applicability of DNA markers coupled with rapid DNA detection by gold nanoparticles to traceability of various liquid foods, including wines, condiments, and soft drinks. Our results revealed that the gold nanoparticles afford colorimetric identification of DNA markers in liquors, condiments, and milk with a quick (≤5 min) “yes” or “no” readout depending on the solution color. Importantly, the DNA markers stored in these liquid foods remain chemically stable and bioactive in hybridization within months, thereby allowing for barcoding liquid foods with considerably long shelf lives. Given the nutritional value of nucleic acids and the direct DNA identification avoiding complicated isolation and analysis, the present work could provide a practical approach to food traceability.

Introducing DNA Nanosensor to Undergraduate Students: Rapid Non-Cross-Linking Aggregation of DNA-Functionalized Gold Nanoparticles for Colorimetric DNA Assay

“…Indeed, detection of DNA has implications in many fields, such as diagnosis, 11 data storage, 18 and food traceability. 14,16 ■ EXPERIMENTAL PROCEDURE…”

“…Students will therefore gain a good understanding of the mechanism of various AuNP-based detection kits and test strips. Indeed, detection of DNA has implications in many fields, such as diagnosis, data storage, and food traceability. , …”

“…The inconvenience and long waiting time may make it an unideal show to students. Recently, aggregation of DNA-AuNPs through terminal DNA base pair stacking, namely, non-cross-linking aggregation, has also emerged as a rapid and effective tool for nucleic acid detection. − To our knowledge and experience so far, even undergraduate students after a short training can synthesize DNA-AuNPs themselves in a general laboratory and achieve clear detection results for specific DNA sequences with very high reproducibility. We thereby suggest the visual demonstration of DNA detection in the non-cross-linking mode be an ideal aid for undergraduate and advanced high school biology and chemistry courses.…”

Demonstration of a Magic Reaction: Accelerating DNA Functionalization of Gold Nanoparticles by Freezing

“…Due to their increasing importance to and impact on our everyday life, nanomaterials including gold nanoparticles (AuNPs) have been increasingly incorporated into undergraduate chemistry curricula. , As one of the best-known hybrid nanomaterials, DNA-functionalized gold nanoparticles (DNA-AuNPs) are often introduced by experienced lecturers. , They have been widely used in advanced colorimetric detection of many targeted analytes that help improve social hygiene and personal healthcare in our daily lives. For instance, DNA-AuNPs have been routinely used for the detection of many biomolecules and toxins, including DNA and heavy metal ions. − In undergraduate teaching, demonstration of visual detection using DNA-AuNPs further offers an exciting experience for students, since this will connect frontier concepts in chemistry to traditional course content from textbooks, expanding the students’ horizon of chemistry . The commonly used method for preparing DNA-AuNPs refers to the salt-aging method, , which involves the use of high-concentration salt to reduce the electrostatic repulsion for enhancing the number of DNA attached to AuNPs.…”

A microscopic survey on microplastics in beverages: the case of beer, mineral water and tea

“…Although numerous studies were carried out on microplastic detection in foods, 6 salts 7 and drinks, 8,9 it has remained an open question whether microplastic contamination of food is a common fact worldwide, and if so, what is the composition of these microplastics. 10 The information is important, and may have implications in filling the knowledge gap of microplastic ingestion, 4 food production and traceability 11 and health risk assessment. 12…”