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1.
Frontiers of Medicine ; (4): 157-175, 2022.
Article in English | WPRIM | ID: wpr-929191

ABSTRACT

Cancer imposes a severe threat to people's health and lives, thus pressing a huge medical and economic burden on individuals and communities. Therefore, early diagnosis of cancer is indispensable in the timely prevention and effective treatment for patients. Exosome has recently become an attractive cancer biomarker in noninvasive early diagnosis because of the unique physiology and pathology functions, which reflects remarkable information regarding the cancer microenvironment, and plays an important role in the occurrence and evolution of cancer. Meanwhile, biosensors have gained great attention for the detection of exosomes due to their superior properties, such as convenient operation, real-time readout, high sensitivity, and remarkable specificity, suggesting promising biomedical applications in the early diagnosis of cancer. In this review, the latest advances of biosensors regarding the assay of exosomes were summarized, and the superiorities of exosomes as markers for the early diagnosis of cancer were evaluated. Moreover, the recent challenges and further opportunities of developing effective biosensors for the early diagnosis of cancer were discussed.


Subject(s)
Biomarkers, Tumor , Biosensing Techniques , Early Detection of Cancer , Exosomes/pathology , Humans , Neoplasms/pathology , Tumor Microenvironment
2.
Acta Pharmaceutica Sinica B ; (6): 2344-2361, 2021.
Article in English | WPRIM | ID: wpr-888806

ABSTRACT

Recent infectious disease outbreaks, such as COVID-19 and Ebola, have highlighted the need for rapid and accurate diagnosis to initiate treatment and curb transmission. Successful diagnostic strategies critically depend on the efficiency of biological sampling and timely analysis. However, current diagnostic techniques are invasive/intrusive and present a severe bottleneck by requiring specialist equipment and trained personnel. Moreover, centralised test facilities are poorly accessible and the requirement to travel may increase disease transmission. Self-administrable, point-of-care (PoC) microneedle diagnostic devices could provide a viable solution to these problems. These miniature needle arrays can detect biomarkers in/from the skin in a minimally invasive manner to provide (near-) real-time diagnosis. Few microneedle devices have been developed specifically for infectious disease diagnosis, though similar technologies are well established in other fields and generally adaptable for infectious disease diagnosis. These include microneedles for biofluid extraction, microneedle sensors and analyte-capturing microneedles, or combinations thereof. Analyte sampling/detection from both blood and dermal interstitial fluid is possible. These technologies are in their early stages of development for infectious disease diagnostics, and there is a vast scope for further development. In this review, we discuss the utility and future outlook of these microneedle technologies in infectious disease diagnosis.

3.
Chinese Journal of Biotechnology ; (12): 3890-3904, 2021.
Article in Chinese | WPRIM | ID: wpr-921474

ABSTRACT

Clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats -associated protein (CRISPR/Cas) has been developed as a precise, efficient, affordable and sensitive nucleic acid detection tool due to its efficient targeted binding ability and programmability. At present, biosensors based on CRISPR-Cas system have shown excellent performance in the detection of nucleic acid of pathogens, which has attracted widespread attention, and is expected to replace the conventional detection methods. This review summarizes the latest research progress of biosensors based on CRISPR/Cas system for detecting nucleic acid of pathogens.


Subject(s)
Biosensing Techniques , CRISPR-Cas Systems/genetics , Nucleic Acids/genetics
4.
Braz. arch. biol. technol ; 64: e21210030, 2021. graf
Article in English | LILACS | ID: biblio-1339317

ABSTRACT

Abstract Nowadays, a prompt and reliable diagnosis is one of the most critical measures for leprosy control. The current diagnostic is based on clinical exams by a health care professional, and it may not recognize early signs of the disease. Therefore, other leprosy diagnosis methods are needed that are sensitive, disease-specific, and easy to deliver to the end-user. This study describes the construction of an electrochemical DNA biosensor to detect PCR products of Mycobacterium leprae using methylene blue as an indicator of the hybridization. The capture probe was immobilized on the graphite electrode modified with poly(4-aminophenol). The electrode surface was morphologically characterized by atomic force microscopy. Linear voltammetry was used to monitor the concentration of methylene blue on the DNA biosensor, which indicated a limit detection of 1 x 10-10 mol/L. The biosensor showed selective when placed to hybridize with a non-complementary sequence. This study suggests that the electrochemical DNA biosensor developed is promising for detecting DNA of Mycobacterium leprae.


Subject(s)
Biosensing Techniques , Aminophenols , Methylene Blue , Mycobacterium leprae
5.
Chinese Journal of Biotechnology ; (12): 1677-1696, 2021.
Article in Chinese | WPRIM | ID: wpr-878661

ABSTRACT

Fermentative production of amino acids is one of the pillars of the fermentation industry in China. Recently, with the fast development of metabolic engineering and synthetic biology technologies, the metabolic engineering for production of amino acids has been flourishing. Conventional forward metabolic engineering, reversed metabolic engineering based on omics data and in silico simulation, and evolutionary metabolic engineering mimicking the natural evolution, have shown increasingly promising applications. A series of highly efficient and robust amino acids-producing strains have been developed and applied in the industrial production of amino acids. The increasingly fierce market competition has put forward new requirements for strain breeding and selection, such as developing high value-added amino acids, dynamic regulation of cellular metabolism, and adapting to the requirements of new process. This review summarizes the advances and prospects in metabolic engineering for the production of amino acids.


Subject(s)
Amino Acids , China , Corynebacterium glutamicum/genetics , Metabolic Engineering , Synthetic Biology
6.
Chinese Journal of Biotechnology ; (12): 1603-1618, 2021.
Article in Chinese | WPRIM | ID: wpr-878657

ABSTRACT

Corynebacterium glutamicum is an important workhorse of industrial biotechnology, especially for amino acid bioindustry. This bacterium is being used to produce various amino acids at a level of over 6 million tons per year. In recent years, enabling technologies for C. glutamicum metabolic engineering have been developed and improved, which accelerated construction and optimization of microbial cell factoriers, expanding spectra of substrates and products, and facilitated basic researches on C. glutamicum. With these technologies, C. glutamicum has become one of the ideal microbial chasses. This review summarizes recent key technological developments of enabling technologies for C. glutamicum metabolic engineering and focuses on establishment and applications of CRISPR-based genome editing, gene expression regulation, adaptive laboratory evolution, and biosensor technologies.


Subject(s)
Amino Acids , Biotechnology , Corynebacterium glutamicum/genetics , Gene Editing , Metabolic Engineering
7.
Chinese Journal of Biotechnology ; (12): 911-922, 2021.
Article in Chinese | WPRIM | ID: wpr-878603

ABSTRACT

Transcription factor-based biosensors (TFBs) play an essential role in metabolic engineering and synthetic biology. TFBs sense the metabolite concentration signals and convert them into specific signal output. They hold high sensitivity, strong specificity, brief analysis speed, and are widely used in response to target metabolites. Here we reviewe the principles of TFBs, the application examples, and challenges faced in recent years in microbial cells, including detecting target metabolite concentrations, high-throughput screening, adaptive laboratory evolutionary selection, and dynamic control. Simultaneously, to overcome the challenges in the application, we also focus on reviewing the performance tuning strategies of TFBs, mainly including traditional and computer-aided tuning strategies. We also discuss the opportunities and challenges that TFBs may face in practical applications, and propose the future research trend.


Subject(s)
Biosensing Techniques , Gene Expression Regulation , Metabolic Engineering , Synthetic Biology , Transcription Factors/metabolism
8.
Chinese Journal of Biotechnology ; (12): 541-560, 2021.
Article in Chinese | WPRIM | ID: wpr-878581

ABSTRACT

Nano-metallic materials are playing an important role in the application of medicine, catalysis, antibacterial and anti-toxin due to their obvious advantages, including nanocrystalline strengthening effect, high photo-absorptivity, high surface energy and single magnetic region performance. In recent years, with the increasing consumption of global petrochemical resources and the aggravation of environmental pollution, nanomaterials based on bio-based molecules have aroused great concern. Bio-based molecules refer to small molecules and macromolecules directly or indirectly derived from biomass. They usually have good biocompatibility, low toxicity, degradability, wide source and low price. Besides, most bio-based molecules have unique physical, chemical properties and physiological activity, such as optical activity, acid/alkali amphoteric property, hydrophilic property and easy coordination with metal ions. Thus, the corresponding nano-materials based on bio-based molecules also have unique functions, such as anti-inflammatory, anti-cancer, anti-oxidation, antiviral fall blood sugar and blood fat etc. In this paper, we give a comprehensive overview of the preparation and application of nano-metallic materials based on bio-based molecules in recent years.


Subject(s)
Anti-Infective Agents , Catalysis , Metals , Nanostructures
9.
Article in Chinese | WPRIM | ID: wpr-865667

ABSTRACT

In this study, an electrochemical DNA biosensor was developed using a straightforward methodology to investigate the interaction of indinavir with calf thymus double-stranded deoxyribonucleic acid (ct-dsDNA) for the first time. The decrease in the oxidation signals of deoxyguanosine (dGuo) and deoxy-adenosine (dAdo), measured by differential pulse voltammetry, upon incubation with different con-centrations of indinavir can be attributed to the binding mode of indinavir to ct-dsDNA. The currents of the dGuo and dAdo peaks decreased linearly with the concentration of indinavir in the range of 1.0-10.0μg/mL. The limit of detection and limit of quantification for indinavir were 0.29 and 0.98μg/mL, respectively, based on the dGuo signal, and 0.23 and 0.78μg/mL, respectively, based on the dAdo signal. To gain further insights into the interaction mechanism between indinavir and ct-dsDNA, spectroscopic measurements and molecular docking simulations were performed. The binding constant (Kb) between indinavir and ct-dsDNA was calculated to be 1.64 × 108 M-1, based on spectrofluorometric measure-ments. The obtained results can offer insights into the inhibitory activity of indinavir, which could help to broaden its applications. That is, indinavir can be used to inhibit other mechanisms and/or hallmarks of viral diseases.

10.
Article in Chinese | WPRIM | ID: wpr-880404

ABSTRACT

Breast cancer is one of the most serious diseases threatening women's life and health in the world, and the mortality rate is the second in the world. With the progress of nanotechnology and the advantages of nanomaterials in the field of electrochemistry and biosensor, various nanomaterials have been applied in electrochemical biosensors. This makes the electrochemical nano-biosensor in the field of rapid detection of breast cancer has been widely concerned and studied. This paper introduces the important components of electrochemical nano-biosensor for breast cancer detection and the research progress of each component in breast cancer detection, as well as the performance of electrochemical nano biosensor in breast cancer detection and the prospect of its application.


Subject(s)
Biosensing Techniques , Breast Neoplasms/diagnosis , Electrochemical Techniques , Female , Humans , Nanostructures , Nanotechnology
11.
Chinese Journal of Biotechnology ; (12): 1060-1068, 2020.
Article in Chinese | WPRIM | ID: wpr-826870

ABSTRACT

Fluorescent proteins can be used as probes to investigate intercellular molecular interactions and trace the pathway of specific metabolites, thus providing a detailed and accurate description of various metabolic processes and cellular pathways in living cells. Nowadays, the existing fluorescent proteins cover almost all spectral bands from ultraviolet to far-red. These fluorescent proteins have been applied in many fields of bioscience with the help of high-resolution microscopy, making great contributions to the development of biology. It is generally agreed that orange fluorescent proteins refer to the fluorescent proteins at the spectral range of 540-570 nm. In recent years, researches on orange fluorescent proteins have made great progress, and they have been widely applied in the field of biology and medicine as reporter protein and fluorescence resonance energy transfer as fluorescent receptor. This paper reviews the studies in the field of orange fluorescent proteins over the last 15 years, with the special focus on the development and application of orange fluorescent proteins to provide the basis for the future studies.


Subject(s)
Biosensing Techniques , Fluorescence Resonance Energy Transfer , Luminescent Proteins , Metabolism , Research
12.
Article in Chinese | WPRIM | ID: wpr-878790

ABSTRACT

A highly specific electrochemical biosensor based on T-Hg~(2+)-T structure for fast screening trace Hg~(2+) in complex animal drug matrix was constructed by cyclic voltammetry(CV) and differential pulse voltammetry(DPV). In the presence of Hg~(2+), it can be specifically binded to the T base of DNA sequence on the surface of modified gold electrode, which changes the conformation of DNA molecule and the electrochemical signal. The concentration ratio of EDC/NHS, the concentration ratio of FC-DNA and the reaction time of the biosensor were optimized by the index of sensitivity and reproducibility in CV. The results showed that the stability of the biosensor was good within 3 days(RSD≤1.3%), the difference between batches was low(RSD=4.7%), and the specificity of the biosensor was high in the presence of interfering ions(As~(3+), Cd~(2+), Cu~(2+), Pb~(2+), Zn~(2+) and Fe~(3+)). DPV results showed that the peak current signal value has a linear relationship with the lgC_((Hg)) over a concentration range from 0.1 nmol·L~(-1) to 1.0 μmol·L~(-1) with a detection limit of 0.066 nmol·L~(-1). Finally, the recovery rate tested in the matrix of animal medicine was satisfactory as 99.17%-101.3%, which can meet the needs of the determination of trace Hg~(2+) in the matrix of Bombyx Batryticatus, and provide a new idea for the rapid screening of trace heavy metals in the matrix of other types of complex traditional Chinese medicine.


Subject(s)
Animals , Biosensing Techniques , DNA/genetics , Electrochemical Techniques , Gold , Mercury , Reproducibility of Results
13.
Chinese Journal of Biotechnology ; (12): 2779-2790, 2020.
Article in Chinese | WPRIM | ID: wpr-878529

ABSTRACT

Bile acids facilitate the absorption of lipids, and affect the development of various diseases by regulating intestinal flora structure and modulating immunity and metabolism. It is therefore important to quantitatively detect bile acids. Current analytical methods are still immature due to constituent complexity, structural heterogeneity and bioactive variability of bile acids. Detection of individual bile acids is of significance for pharmacological research, clinical diagnosis and disease prevention. Advances have been made in bile acid analysis from multiple sources including serum, bile, urine and feces, although several limitations still exist for bile acid quantification. Here we review research progress in conventional bile acid assays, including spectrophotometry, thin-layer chromatography, liquid/gas chromatography and liquid/gas chromatography-mass spectrometry. Moreover, we emphasize the development of bile acid biosensors that may have promising prospects.


Subject(s)
Bile , Bile Acids and Salts , Biosensing Techniques , Chromatography, Thin Layer , Gas Chromatography-Mass Spectrometry
14.
Article | IMSEAR | ID: sea-209858

ABSTRACT

A highly sensitive ethanol biosensor based on Acetobacter aceti biofilm, which contains pyrroloquinolinequinone-alcohol dehydrogenase enzyme for halal detection in food and beverages, has been developed. In thisstudy, A. aceti cells were purified by determining the conditions of growth time, incubation temperature, andpH to suppress the yeast growth. Selection of optimum conditions for biofilm formation was also carried out toobtain a stable sensor operation. The optimum biofilm formation was 14 days. The performance of biosensor wasinvestigated by the cyclic voltammetry technique. Linear range, sensitivity, limit of detection (LOD), and limitof quantification (LOQ) were found to be 5 × 10−5–3 × 10−4 %, 43,076 µA %−1, 2.32 × 10−5, and 7.03 × 10−5 %,respectively. The repeatability of biosensor was tested in 1 × 10−5 − 1% ethanol concentration and the relativestandard deviation was 1.08% (for n = 7). The stability studies have shown that the cyclic voltammetry responseof biosensor to ethanol leave the act of 98.99% at the 7 week. Thus, the developed biosensor is promising to beused for simple analysis of halal products and has been tested on real sample.

15.
Article | IMSEAR | ID: sea-204979

ABSTRACT

The use of laser and optoelectronics concepts to develop biological detection systems is the goal of this work. A biosensor based on one of the interferometer techniques, Mach-Zhender interferometer (MZI) technique, and the using of the laser beam is developed for pregnancy detection or pregnancy hormone, Human chorionic gonadotropin (HCG), increasing. A part of photonic crystal fiber (PCF) with 3 different lengths (1.5 cm, 1.0 cm, and 0.5 cm) has been collapsed with 2 conventional single mode fibers (SMFs) to achieve MZI technique, Micro-holes collapsing and make high sensitive regions for the optical properties (refractive index and absorption) in the urine sample. This type of laser biosensor depends on light intensity measurement through a modified optical fiber. The sensing region is immersed in different urine samples of pregnant female and non-pregnant female. Biological changes in the urine sample due to the HCG increasing lead to a change in the optical properties (refractive index and absorption) of the urine sample. The results showed that the increasing of pregnancy hormones leads to an increase in the refractive index for a urine sample and a decrease in the intensity of the output laser beam. From this test, the calibration curve of laser biosensor for a pregnancy test or pregnancy detection has been found. The sensitivities of the laser biosensor with a refractive index in the range (1.33864-1.34257) at (1.5 cm, 1.0 cm, and 0.5 cm) PCF length are 61.142 ABS/ RIU, 4.5132 ABS/RIU and 2.888 ABS/RIU, respectively. Thus, the highest sensitivity was found for the (1.5 cm) photonic crystal fiber length.

16.
Article in Chinese | WPRIM | ID: wpr-742925

ABSTRACT

In recent years, more and more attention has been paid to the integration of nano-material graphene and field effect transistor to construct biosensor for detecting biomolecules.This is mainly due to the following advantages of graphene field effect transistor inculding high sensitivity and specificity, rapid analysis, label-free detection, cheap price, miniaturization and integration.This review summarizes the structure and working principle of graphene field effect transistor biosensor, the preparation and functionalization of graphene, and the application of graphene field effect transistor in medical detections.

17.
Article in English | WPRIM | ID: wpr-780693

ABSTRACT

Abstract@#Introduction: There are various methods in cholesterol analysis, for example, amperometric, enzymatic, and electrochemistry. Those methods are not expressing the suitable methods for cholesterol analysis because of the complicated and long procedure. Methods: This experiment is developing cholesterol analysis methods using enzyme immobilization techniques. The enzyme, cholesterol oxidase, immobilized on polyaniline surface conducted chitosan and formed a biosensor. Polyaniline matrix bound to chitosan in a covalent bond, a strong bonding that acts as an enzyme’s trap. Results: The optimal biosensor has 650 nm maximum wavelength and optimum pH at 7. Immobilization process occurs in 24 hours. The biosensor has 8 minutes response time and can be used one time during 2 weeks active time. The biosensor responses increase linearly at range 0.1 mg/mL and 2.5 mg/mL. The sensitivity at 0.304 mg/ml and accurate value at 89.72%. The detection limit and quantity limit are at 0.00521 mg/mL and 0.0197 mg/mL. Conclusion: The result showed that this method can be used as an eco-friendly material for a biosensor. This method can be developed by using the suitable crosslinker for enzyme-surface to enhance biosensor performance.

18.
Article in Chinese | WPRIM | ID: wpr-732762

ABSTRACT

With the rapid development of nanotechnology,nanomaterials have received more and more attention in the application of medical transformation researches.As a new type of multifunctional inorganic nanomaterial with particle size between 1 to 100 nm,zinc oxide nanoparticles not only has common nano-effects including high specific surface area,quantum size and macroscopic tunneling,but also has some important special effects in optical,catalytic and biological aspects showing a wide range of application prospects.In recent years,with the deepening of the physicochemical properties and special effects of zinc oxide nanoparticles,its application in biomedical fields has gradually become a research hotspot in the field of biomedicine,such as molecular fluorescence probe,antibacterial,biosensor,drug carrier,and photochemical therapy of tumor.In this paper,the special effects of zinc oxide nanoparticles on optical,catalytic and biological aspects were highlighted,and its research progress was reviewed in medical imaging applications such as molecular imaging localization,biosignal sensing and molecular recognition,drug carrier development and tumor therapy.Furthermore,the problems in the translational application of zinc oxide nanoparticles were discussed.

19.
Article in Chinese | WPRIM | ID: wpr-664906

ABSTRACT

VisualiZation detection methods are used for determination of the concentration of unknown target by comparing the color change in the intensity or type of reaction solution by naked eye.VisualiZation detection method has some advantages such as simple and rapid operation, low detection cost, fast reaction speed, and detecting target concentration by means of naked eye.Gold nanomaterials are widely used in the construction of visual biosensors due to its unique optical properties.For example, when changing the distance or morphology of the particles, the plasmon resonance absorption peak of local surface will change accordingly.Herein, we reviewed the application of gold nanomaterials in visualiZation biosensors for the detection of target molecules, summed up the main problems of AuNP colormertic methods in the determination of actual samples, and provided an outlook of the future of gold nanoparticles-based biosensor in application development.

20.
Article in Chinese | WPRIM | ID: wpr-692345

ABSTRACT

The low sensitivity of microbial fuel cell ( MFC)-biosensor is one of the bottlenecks in its practical application. To investigate the effect of anode electrode modified with carbon nanomaterials on the sensitivity of water toxicity detection of MFC-based biosensor, graphite felts ( GF ) were modified using two carbon nanomaterials of multi-walled carbon nanotubes ( MWNT ) and conductive carbon black ( GCB ) . MFC biosensors were started up with the anode electrodes, and the results showed that resistance of the GCB and MWNT-modified electrode was smaller than that of unmodified electrode, and the order of MFC power output was GCB/GF-MFC (2. 63 W/m2)>MWNT/GF-MFC (2. 56 W/m2)>GF-MFC (2. 09 W/m2). Then, 3, 5-dichlorophenol poison ( DCP) was used as a model toxicant in toxicity test, the order of toxicity inhibition ratios of 10 mg/L DCP to three MFC biosensor was MWNT/GF-MFC (31. 8% )>GCB/GF-MFC (26. 3% )>GF-MFC (20. 1% ). The sensitivity for toxicity detection by MFC biosensors with anode electrode modified with carbon nanomaterials was improved, and MWNT/GF-MFC had the highest sensitivity. The result of the study may promote the application of MFC biosensor in water pollution monitoring.

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