Rapid and accurate detection of pathogenic bacteria is crucial for various applications, including public health and food safety. However, existing bacteria detection techniques have several drawbacks as they are inconvenient and require time-consuming procedures and complex machinery. Recently, the precision and versatility of CRISPR/Cas system has been leveraged to design biosensors that offer a more efficient and accurate approach to bacterial detection compared to the existing techniques. Significant research has been focused on developing biosensors based on the CRISPR/Cas system which has shown promise in efficiently detecting pathogenic bacteria or virus. In this review, we present a biosensor based on the CRISPR/Cas system that has been specifically developed to overcome these limitations and detect different pathogenic bacteria effectively including Vibrio parahaemolyticus, Salmonella, E. coli O157:H7, and Listeria monocytogenes. This biosensor takes advantage of the CRISPR/Cas system's precision and versatility for more efficiently accurately detecting bacteria compared to the previous techniques. The biosensor has potential to enhance public health and ensure food safety as the biosensor’s design can revolutionize method of detecting pathogenic bacteria. It provides a rapid and reliable method for identifying harmful bacteria and it can aid in early intervention and preventive measures, mitigating the risk of bacterial outbreaks and their associated consequences. Further research and development in this area will lead to development of even more advanced biosensors capable of detecting an even broader range of bacterial pathogens, thereby significantly benefiting various industries and helping in safeguard human health

Phytohormones (plant hormones) are a class of small-molecule organic compounds synthesized de novo in plants. Although phytohormones are present in trace amounts, they play a key role in regulating plant growth and development, and in response to external stresses. Therefore, the analysis and monitoring of phytohormones have become an important research topic in precision agriculture. Among the various detection methods, electrochemical analysis is favored because of its simplicity, rapidity, high sensitivity, and in-situ monitoring. Graphene and graphene-like carbon materials have abundant sources, exhibiting large specific surface area, and excellent physicochemical properties. Thus, they have been widely used in the preparation of electrochemical biosensors for phytohormone detection. In this paper, the research advances of electrochemical sensors based on graphene and graphene-like carbon materials for phytohormone detection have been reviewed. The properties of graphene and graphene-like carbon materials are first introduced. Then, the research advances of electrochemical biosensors (including conventional electrochemical sensors, photoelectrochemical sensors, and electrochemiluminescence sensors) based on graphene and graphene-like carbon materials for phytohormone detection is summarized, with emphasis on their sensing strategies and the roles of graphene and graphene-like carbon materials in them. Finally, the development of electrochemical sensors based on graphene and graphene-like carbon materials for phytohormone detection is prospected.

In the past decade, there has been phenomenal progress in the field of nanomaterials, especially in the area of carbon nanotubes (CNTs). In this review, we have elucidated a contemporary synopsis of properties, synthesis, functionalization, toxicity, and several potential biomedical applications of CNTs. Researchers have reported remarkable mechanical, electronic, and physical properties of CNTs which makes their applications so versatile. Functionalization of CNTs has been valuable in modifying their properties, expanding their applications, and reducing their toxicity. In recent years, the use of CNTs in biomedical applications has grown exponentially as they are utilized in the field of drug delivery, tissue engineering, biosensors, bioimaging, and cancer treatment. CNTs can increase the lifespan of drugs in humans and facilitate their delivery directly to the targeted cells; they are also highly efficient biocompatible biosensors and bioimaging agents. CNTs have also shown great results in detecting the SARS COVID-19 virus and in the field of cancer treatment and tissue engineering which is substantially required looking at the present conditions. The concerns about CNTs include cytotoxicity faced in in vivo biomedical applications and its high manufacturing cost are discussed in the review.

Abstract Biosensors are a group of measurement systems and their design is based on the selective identification of analyses based on biological components and physical and chemical detectors. Biosensors consist of three components: biological element, detector, and converter. The design of biosensors in various fields of biological sciences, medicine has expanded significantly. Biosensor technology actually represents a combination of biochemistry, molecular biology, chemistry, physics, electronics, and telecommunications. A biosensor actually consists of a small sensor and biological material fixed on it. Because biosensors are a powerful tool for identifying biological molecules, today they are used in various medical sciences, chemical industry, food industry, environmental monitoring, pharmaceutical production, health, etc. In fact, these sensors are a powerful tool to identify biological molecules. In fact, biosensors are analytical tools that can use biological intelligence to detect and react with a compound or compounds, and thus create a chemical, optical, or electrical message. The basis of a biosensor is to convert a biological response into a message. In this category, the use of telecommunication engineering technology and electromagnetic waves and frequency and radio spectrum is growing more and more to detect, measure, and determine the desired parameters in microbiology and laboratory sciences. The use of radio, optical, electromagnetic, ultrasonic, and infrared wave detection technology is part of the applications of telecommunication science in this field. Even image and audio processing systems have been instrumental in the discussion of biosensors in microbiology. The science of using fiber optics and waveguides, micro-strip antennas, and microelectromechanical technology is also very efficient in the construction and design of these biosensors.

사람이 섭취하는 식품 내의 항생제, 알레르기 유발 물질, 병원균 및 기타 오염물질의 수준을 모니터링하기 위해서는, 빠르고 정확하며 저렴한 비용으로 테스트 해야 한다. 이러한 문제 중 일부를 해결하기 위해 지난 10-15년 동안 진보된 기술(label-free biosensor assays)이 개발되어 왔다. 이 면역감지키트들은 실시간 측정이 가능하고, 높은 수준의 자동화를 제공하며, 향상된 처리율과 민감도를 가지고 있다. 또한, 기존의 방법과 비교하여 가격이 저렴하고, 덜 복잡하며, 분석 시간을 단축시켜주는 사용자 친화 적 키트이다. 이 리뷰에서는 면역감지키트의 장단점, 그리고 미래의 식품안전검사에서의 사용성에 관한 것에 대해 논의해 볼 것이다.

본 연구의 목적은 식품 제조 중 표백 및 살균에 사용되는 과산화수소(H2O2)의 잔류 농도 검출에 활용 될 수 있는 유리탄소전극 기반의 바이오센서의 개발이다. 미국 FDA 및 국내 식품의학안전처 등 식품 용 과산화수소(food grade H2O2)는 국내외적으로 35% H2O2 수용액으로 규정한다. 연구에서 개발한 바이오센서는 감응 물질로 사용된 horseradish peroxidase를 graphene oxide와 aniline과 함께 biocomposite 를 형성시킨 후 중성 pH에서 본 연구에서 새롭게 개발된 전기화학적 증착법을 수행하여 개발되었다. 센서구조 및 특성 평가를 위하여 SEM, 순환 전압 전류법 등을 수행하 였으며 본 연구에서 개발된 바이오센서는 10-500 μM 농 도의 H2O2에 대하여 직선상의 농도 의존적인 반응을 나타내었으며 최저 검출 한계는 0.12 μM 으로 산출되었다. 본 연구에서 개발된 센서의 전략적 가치는 향후 오징어포,건어물 등 널리 유통되는 식품 중에 함유된 식품용 H2O2 미량을 현장에서 쉽게 분석 할 수 있어서 비용-효과적 측면에서 그 가치가 우수하다는 것을 제시한다.

Conjugated nanocrystals using CdSe/ZnS core/shell nanocrystal quantum dots modified by organic linkers and glucose oxidase (GOx) were prepared for use as biosensors. The trioctylphophine oxide (TOPO)-capped QDs were first modified to give them water-solubility by terminal carboxyl groups that were bonded to the amino groups of GOx through an EDC/NHS coupling reaction. As the glucose concentration increased, the photoluminescence intensity was enhanced linearly due to the electron transfer during the enzymatic reaction. The UV-visible spectra of the as-prepared QDs are identical to that of QDs-MAA. This shows that these QDs do not become agglomerated during ligand exchanges. A photoluminescence (PL) spectroscopic study showed that the PL intensity of the QDs-GOx bioconjugates was increased in the presence of glucose. These glucose sensors showed linearity up to approximately 15 mM and became gradually saturated above 15 mM because the excess glucose did not affect the enzymatic oxidation reaction past that amount. These biosensors show highly sensitive variation in terms of their photoluminescence depending on the glucose concentration.

The biosensor technology, which makes it possible to detect biomaterial such as protein, pathogen, and small molecules, is useful in such areas as diagnosis, bioprocessing, and food analysis or safety. For the development of a highly sensitive biosensor, immobilization techniques of organic/bio films on solid substrate, and detection methods of protein-protein reactions appearing in a few nanometers region from the sensor surface should be established. In this review, several immobilization techniques and detection methods are reviewed based on the articles reported recently.

SPR biosensors which belong to a family of thin film refractometry-based sensors measure refractive index changes produced by biomolecular interactions occurring at the surface of the sensors. The main advantage of SPR biosensors is to detect molecular interactions directly without the use of labels. This feature makes them possible to observe biomolecular interactions in real-time or near real-time. The non-specific binding between ligand and target analyte may, however, produce a false refractive index change resulting in false sensor response. The applications of SPR biosensors have involved biomolecular interaction kinetics analysis, affinity measurement, screening and concentration assay, and so on.