Search

Surface enhanced Raman scattering (SERS) DNA biosensing is an ultrasensitive, selective, and rapid detection technique with the ability to produce molecule-specific distinct fingerprint spectra. It supersedes the long amplicon based PCR assays, the fluorescence and spectroscopic techniques with their quenching and narrow spectral bandwidth, and the electrochemical detection techniques using multiplexing. However, the performance of the SERS DNA biosensor relies on the DNA probe length, platform composition, both the presence and position of Raman tags and the chosen sensing strategy. In this context, we herein report a SERS biosensor based on dual nanoplatforms with a uniquely designed Raman tag (ATTO Rho6G) intercalated short-length DNA probe for the sensitive detection of the pig species Sus scrofa. In the design of the signal probe (SP), a Raman tag was incorporated adjacent to the spacer arm, followed by a terminal thiol modifier, which consequently had a strong influence on the SERS signal enhancement. The detection strategy involves the probe-target DNA hybridization mediated coupling of the two platforms, i.e., the graphene oxide-gold nanorod (GO-AuNR) functionalized capture probe (CP) and SP-conjugated gold nanoparticles (AuNPs), consequently enhancing the SERS intensity by both the electromagnetic hot spots generated at the junctions or interstices of the two platforms and the chemical enhancement between the AuNPs and the adsorbed intercalated Raman tag. This dual platform based SERS DNA biosensor exhibited outstanding sensitivity in detecting pork DNA with a limit of detection (LOD) of 100 aM validated with DNA extracted from a pork sample (LOD 1 fM). Moreover, the fabricated SERS biosensor showed outstanding selectivity and specificity for differentiating the DNA sequences of six closely related non-target species from the target DNA sequences with single and three nucleotide base-mismatches. Therefore, the developed short-length DNA linked dual platf

The integration of metal, metal oxides or metal alloy nanostructures with graphene increases the surface area, active sites for binding analytes, conductivity as well as mechanical strength of the biosensor. Graphene-metallic nanocomposites by their synergistic effect exhibit greater sensitivity for the detection of a variety of biomolecules. Herein, this review addresses the most recent progress on the design and fabrication of graphene metallic nano-biointerfaces in electrochemical biosensing, detection of biomolecules ranging from most common analytes to sophisticated molecules with greater sensitivity as well as good selectivity from the real-time sample in presence of common interfering substances.

Recently, falsified meat products have become a serious problem. Many issues such as public health, fair trade, and religious consideration are directly influenced by adulterations of meat. To overcome this problem, various analytical methods, based on physical, chemical, anatomical, histological, and biological approaches are being utilized to identify meat species. Nevertheless, by virtue of their inherent limitations, most of these methods have been replaced by more accurate and sensitive detection methods, such as DNA-based molecular techniques. This review highlights the most extensive and updated overview of meat species identification based on DNA hybridization techniques. It will be demonstrated that the DNA-hybridization method is a highly sensitive method in analyzing the similarity of DNA strands, where the limit of detections was reported to be from 0.1% to less than 0.01%, depending on the meat species.

Bionano-materials are playing an important role in a number of applications due to their inherent eco-friendly advantages since the last few decades. These materials are being explored as the potential alternatives to traditional synthetic materials for diverse applications with particular emphasis as green reinforcement and offer a number of advantages including considerable toughness, flexibility, easy processing, and recyclability. Indeed, nano-sized materials often display an out-standing equilibrium between toughness and strength and frequently enhanced characteristics of their individual components. The effect of different manufacturing conditions and different surface modification techniques for the bionano- materials as well as their polymer composites is discussed in details. Indeed, bionano-material-reinforced polymer composites are emerging very rapidly as the potential substitute to the metal- or ceramic-based materials in applications including automotive, aerospace, marine, sporting goods, and electronic industries.

Carbon nanotubes (CNTs) is a rigid rod-like nanoscale material produced from carbon in powder, liquid, or gel form via acid or chemical hydrolysis. Due to its unique and exceptional renewability, biodegradability, mechanical, physicochemical properties, and abundance, the incorporation associated with a small quantity of CNTs to polymeric matrices enhance the mechanical and thermal resistance, and also stability of the latter by several orders of magnitude. Moreover, NCC-derived carbon materials are of no serious threat to the environment, providing further impetus for the development and applications of this green and renewable biomaterial for lightweight and degradable composites. Surface functionalization of CNTs remains the focus of CNTs research in tailoring its properties for dispersion in hydrophilic and hydrophobic media. Through functionalization, the attachment of appropriate chemical functionalities between conjugated sp² of CNTs and polymeric matrix is established. It is thus of utmost importance that the tools and protocols for imaging CNTs in a complex matrix and quantify its reinforcement, antimicrobial, stability, hydrophilicity, and biodegradability are be developed.

Bionano-materials are playing an important role in a number of applications due to their inherent eco-friendly advantages since the last few decades. These materials are being explored as the potential alternatives to traditional synthetic materials for diverse applications with particular emphasis as green reinforcement and offer a number of advantages including considerable toughness, flexibility, easy processing, and recyclability. Indeed, nano-sized materials often display an out-standing equilibrium between toughness and strength and frequently enhanced characteristics of their individual components. The effect of different manufacturing conditions and different surface modification techniques for the bionano- materials as well as their polymer composites is discussed in details. Indeed, bionano-material-reinforced polymer composites are emerging very rapidly as the potential substitute to the metal- or ceramic-based materials in applications including automotive, aerospace, marine, sporting goods, and electronic industries.

Carbon nanotubes (CNTs) is a rigid rod-like nanoscale material produced from carbon in powder, liquid, or gel form via acid or chemical hydrolysis. Due to its unique and exceptional renewability, biodegradability, mechanical, physicochemical properties, and abundance, the incorporation associated with a small quantity of CNTs to polymeric matrices enhance the mechanical and thermal resistance, and also stability of the latter by several orders of magnitude. Moreover, NCC-derived carbon materials are of no serious threat to the environment, providing further impetus for the development and applications of this green and renewable biomaterial for lightweight and degradable composites. Surface functionalization of CNTs remains the focus of CNTs research in tailoring its properties for dispersion in hydrophilic and hydrophobic media. Through functionalization, the attachment of appropriate chemical functionalities between conjugated sp² of CNTs and polymeric matrix is established. It is thus of utmost importance that the tools and protocols for imaging CNTs in a complex matrix and quantify its reinforcement, antimicrobial, stability, hydrophilicity, and biodegradability are be developed.