Electrochemical detection of magnetically-entrapped DNA sequences from complex samples by multiplexed enzymatic labelling: Application to a transgenic food/feed quantitative survey

Advances in Electrochemical Techniques for the Detection and Analysis of Genetically Modified Organisms: An Analysis Based on Bibliometrics

Since the first successful transgenic plants obtained in 1983, dozens of plants have been tested. On the one hand, genetically modified plants solve the problems of agricultural production. However, due to exogenous genes of transgenic plants, such as its seeds or pollen drift, diffusion between populations will likely lead to superweeds or affect the original traits. The detection technology of transgenic plants and their products have received considerable attention. Electrochemical sensing technology is a fast, low-cost, and portable analysis technology. This review interprets the application of electrochemical technology in the analysis and detection of transgenic products through bibliometrics. A total of 83 research articles were analyzed, spanning 2001 to 2021. We described the different stages in the development history of the subject and the contributions of countries and institutions to the topic. Although there were more annual publications in some years, there was no explosive growth in any period. The lack of breakthroughs in this technology is a significant factor in the lack of experts from other fields cross-examining the subject. Through keyword co-occurrence analysis, different research directions on this topic were discussed. The use of nanomaterials with excellent electrical conductivity allows for more sensitive detection of GM crops by electrochemical sensors. Furthermore, co-citation analysis was used to interpret the most popular reports on the topic. In the end, we predict the future development of this topic according to the analysis results.

Genetically Modified Soybean Detection Using a Biosensor Electrode with a Self-Assembled Monolayer of Gold Nanoparticles

In this study, we proposed a genosensor that can qualitatively and quantitatively detect genetically modified soybeans using a simple electrode with evenly distributed single layer gold nanoparticles. The DNA sensing electrode is made by sputtering a gold film on the substrate, and then sequentially depositing 1,6-hexanedithiol and gold nanoparticles with sulfur groups on the substrate. Then, the complementary to the CaMV 35S promoter (P35S) was used as the capture probe. The target DNA directly extracted from the genetically modified soybeans rather than the synthesized DNA segments was used to construct the detection standard curve. The experimental results showed that our genosensor could directly detect genetically modified genes extracted from soybeans. We obtained two percentage calibration curves. The calibration curve corresponding to the lower percentage range (1-6%) exhibits a sensitivity of 2.36 Ω/% with R2 = 0.9983, while the calibration curve corresponding to the higher percentage range (6-40%) possesses a sensitivity of 0.1 Ω/% with R2 = 0.9928. The limit of detection would be 1%. The recovery rates for the 4% and 5.7% GMS DNA were measured to be 104.1% and 102.49% with RSD at 6.24% and 2.54%. The gold nanoparticle sensing electrode developed in this research is suitable for qualitative and quantitative detection of genetically modified soybeans and can be further applied to the detection of other genetically modified crops in the future.

Nucleic Acids Analysis

Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nucleic acids and nucleic acids-based analysis have been widely applied in biological studies, clinical diagnosis, environmental analysis, food safety and forensic analysis. During the past decades, the field of nucleic acids analysis has been rapidly advancing with many technological breakthroughs. In this review, we focus on the methods developed for analyzing nucleic acids, nucleic acids-based analysis, device for nucleic acids analysis, and applications of nucleic acids analysis. The representative strategies for the development of new nucleic acids analysis in this field are summarized, and key advantages and possible limitations are discussed. Finally, a brief perspective on existing challenges and further research development is provided.

Proteinase-sculptured 3D-printed graphene/polylactic acid electrodes as potential biosensing platforms: towards enzymatic modeling of 3D-printed structures

3D printing technologies are currently appealing for the research community due to their demonstrated versatility for different scientific applications. One of the most commonly used materials for 3D printing is polylactic acid (PLA), a biodegradable polymer that can be fully or partially digested by enzymes such as proteinase K. This work seeks to exploit PLA's biodegradability to selectively and reproducibly sculpt 3D-printed graphene/PLA surfaces to turn them into sensitive electroactive platforms. Proteinase K-catalyzed digestion of 3D-printed graphene/PLA electrodes is proposed as an environmentally friendly, highly controllable, and reproducible activation procedure of 3D-printed electrodes. Proteinase K digests PLA in a controllable fashion, exposing electroactive graphene sheets embedded within the 3D-printed structures to the solution and therefore achieving a tailorable electrode performance. A proof-of-concept biosensing application is proposed, based on the immobilization of enzyme alkaline phosphatase at the sculptured electrodes with the subsequent electrochemical detection of 1-naphthol in aqueous media. This work attempts to continue demonstrating the potential of 3D printing in electroanalytical applications, as well as to explore the exciting possibilities arising from merging biotechnological processes with these manufacturing procedures.