Biological Detection Research Articles

A multilevel core-shell structure Fe3O4@SiO2@InGaO@SiO2 magnetic particles for DNA extraction

DNA extraction is greatly significant in biological detection fields, including species identification, pathogen detection, environmental monitoring, biosafety, and food safety. Scientific research and practical application must conduct high-quality trace DNA separation, purification and extraction. Herein, a two-step strategy successfully prepares a multilevel core–shell structure Fe3O4@SiO2@InGaO@SiO2 magnetic particles for trace DNA extraction. The morphologies, structures, elemental compositions, components, and properties of the materials are systematically characterized. Fe3O4@SiO2@InGaO@SiO2 magnetic particles in the chaotropic salt solutions are used to directly target DNA binding due to the existence of Si-O–H bond. The maximum DNA adsorption rate can highly reach 83.1 % after 700 °C annealing in the air for 30 min, far exceeding the adsorption rate of commercial reagent kit, which is attributed to the increased specific surface area. The excellent result is conducive to rapid DNA extraction in practical applications, especially in daily criminal cases, further promoting social security and stability.

Broadband NIR emission from Te doped silicate glass as gc-LED light source for biological detection

Near-infrared (NIR) glass-converted light-emitting diodes (gc-LEDs) are newly emergent broadband light sources for miniaturizing optical systems like spectrometers. While lots of effort has been spent on materials doped with rare-earth and transition-metal ions, the achievement of these materials with broadband NIR emission and desired wavelength region remains a long-standing challenge, especially operating in the spectral region between 700 and 1100 nm. Herein, a broadband NIR LEDs based on Te cluster-doped silicate glass is developed. Through adjustment of melting atmosphere and network topology of the glass matrix, active NIR Te cluster centers can be generated and stabilized in silicate glass and show a broad emission at 980 nm with a full width at half maximum (FWHM) of 300 nm under blue light excitation. The photoluminescence of the glass matches well with the absorption of several primary chemical bonds in food and biological tissue. In demonstration experiments, the NIR absorption of different biological tissue by NIR light from our glass is measured, suggesting that the super-broad NIR luminescence of Te-doped silicate glass has potential applications as light sources for nondestructive analysis.

Low-Threshold Anti-Stokes Raman Microlaser on Thin-Film Lithium Niobate Chip.

Raman microlasers form on-chip versatile light sources by optical pumping, enabling numerical applications ranging from telecommunications to biological detection. Stimulated Raman scattering (SRS) lasing has been demonstrated in optical microresonators, leveraging high Q factors and small mode volume to generate downconverted photons based on the interaction of light with the Stokes vibrational mode. Unlike redshifted SRS, stimulated anti-Stokes Raman scattering (SARS) further involves the interplay between the pump photon and the SRS photon to generate an upconverted photon, depending on a highly efficient SRS signal as an essential prerequisite. Therefore, achieving SARS in microresonators is challenging due to the low lasing efficiencies of integrated Raman lasers caused by intrinsically low Raman gain. In this work, high-Q whispering gallery microresonators were fabricated by femtosecond laser photolithography assisted chemo-mechanical etching on thin-film lithium niobate (TFLN), which is a strong Raman-gain photonic platform. The high Q factor reached 4.42 × 106, which dramatically increased the circulating light intensity within a small volume. And a strong Stokes vibrational frequency of 264 cm-1 of lithium niobate was selectively excited, leading to a highly efficient SRS lasing signal with a conversion efficiency of 40.6%. And the threshold for SRS was only 0.33 mW, which is about half the best record previously reported on a TFLN platform. The combination of high Q factors, a small cavity size of 120 μm, and the excitation of a strong Raman mode allowed the formation of SARS lasing with only a 0.46 mW pump threshold.

The function of chemical folic acid in calibration methods and neurodevelopmental disorders.

Functional molecules have been attracting increasing attention in environmental and physiological studies. In particular, folic acid (FA) could be considered a key factor in estimating, adjusting, and making decisions in the treatment of neurodevelopmental disorders. It promotes the general significance and conceptual for considering FA molecular scientific research detections, which implies related advancement in both of biological structure and detection methods. Among these applications, the FA molecule acts as a coenzyme that incorporates carbon atoms and synthesizes purines and pyrimidines. Therefore, the calibration method has real applications and can be used as a sensing platform and for detection approaches, which conveys the internal relationship between the FA molecule and physiological characterization. This mini review briefly discusses multiple FA application fields and detection pathways and could supplement their utilization in anticipation of the onset of disease.

MnO2-based dual channel surface plasmon resonance fiber sensor for trace glutathione and refractive index detection.

Glutathione (GSH) plays vital role in human biological systems, so its rapid and sensitive detection is necessary for health condition monitoring. In this work, a simple structure for dual channel GSH and refractive index (RI) detection is proposed. By introducing Au-MnO2 thin film coating on the fiber surface for the first time, GSH solution would lead to the dissolution of MnO2, the change in GSH levels could be monitored over a short period in channel 2. For channel 1, ITO-Ag thin film is applied for RI change detection. After optimization, the GSH detection sensitivity reached about -2.361 nm/mM in the range of 0.005-50 mM, and the RI sensitivity reached 1704.252 nm/RIU in the range of 1.331-1.3895 RIU. Channel 1 could also put into GSH detection in the high concentration scale to enlarge the sensor's range and 0.095 nm/mM of sensitivity is acquired within the range of 50-600 mM. With the presence of MnO2 film, the detection sensitivity increased 25.663 times. Neither channel interferes with the operation of the other. Proposed sensor provides stability, high selectivity and elevation in GSH detection sensitivity, which shows great potential for environmental and biological detection field and their applications.

Self‐Powered Photodetector Based on Perovskite/Ge Heterojunction with High Responsivity

AbstractSelf‐powered photodetectors (SPDs) are regarded as a new type of photodetectors without external energy sources, exhibiting great potential in the next generation of image sensing, biological detection, and robotics. Here, single crystal CH(NH2)2PbBr3 (FAPbBr3) perovskite with a low trap density of 1.64 × 109 cm−3 is directly integrated onto single crystal germanium (Ge). The band structure of the heterojunction belongs to type‐II alignment type, which is beneficial to the achievement of high responsivity. Therefore, the fabricated Au/FAPbBr3/Ge/Au detector exhibits a high responsivity of 0.33 A W−1, detectivity up to 3.83 × 1011 Jones and relatively fast decay time of 4.94 ms without external bias under 520 nm laser illumination. In addition, a prototype of an imaging system is set up utilizing the photodetector as a sensing pixel, from which the imaging function is verified. This work demonstrates a facile strategy for designing high‐performance SPDs.

Canine detection of explosives under adverse environmental conditions with and without acclimation training.

Canines are one of the best biological detectors of energetic materials available; however, canine detection of explosives is impacted by a number of factors, including environmental conditions. The objectives of this study were: 1) determine how canine detection limits vary when both the canine and odorant are tested in varying temperature and humidity conditions (canine and odor interactive effects); and 2) determine if an acclimatization plan can improve detection limits in an adverse environmental condition. Eight working line canines were trained to detect four energetics: prill ammonium nitrate (AN), Composition 4 (C4), trinitrotoluene (TNT) and double base smokeless powder (SP). In Experiment 1, canines completed a 3-alternative forced choice 3-down-1-up staircase threshold assessment in five environmental conditions: 40°C and 70% relative humidity (RH), 40°C and 40% RH, 0°C and 90% RH, 0°C and 50% RH and 21°C and 50% RH. Canines showed a 3.5-fold detection limit increase (poorer detection) for C4 in 40°C and 70% RH compared to their detection limit at 21°C and 50% RH. In Experiment 2, the eight canines were split into two groups (n = 4), control and acclimation groups. The control group completed the threshold assessment for C4 at 21°C and 50% RH each day for 20 days, with 5 minutes of petting prior to testing. The acclimation group completed the same assessment daily starting at 21°C and 50% RH but temperature and RH were incremented daily over the course of 6 days to the 40°C and 70% RH condition. After the initial six days, the acclimation group completed daily assessments at 40°C and 70% RH condition for the remainder of the experiment. All acclimatization group canines started their session with 5 minutes of toy or food retrieves. Detection limits for C4 for all dogs were tested in 40°C and 70% RH on day 11 and day 22. The acclimatization plan improved detection limits in the 40°C and 70% RH condition for C4 compared to the non-acclimated group. In this set of experiments, canine detection limits for four explosive odorants were found to vary based on environmental condition and were mostly driven by impacts on the canine rather than odor availability. The acclimatization plan did result in lower detection limits (i.e., increased performance). Future work should determine what factor (exercise or environmental exposure) is more effective in acclimatization for odor detection work.

Sensing, Imaging, and Therapeutic Strategies Endowing by Conjugate Polymers for Precision Medicine.

Conjugated polymers (CPs) have promising applications in biomedical fields, such as disease monitoring, real-time imaging diagnosis, and disease treatment. As a promising luminescent material with tunable emission, high brightness and excellent stability, CPs are widely used as fluorescent probes in biological detection and imaging. Rational molecular design and structural optimization have broadened absorption/emission range of CPs, which are more conductive for disease diagnosis and precision therapy. This review provides a comprehensive overview of recent advances in the application of CPs, aiming to elucidate their structural and functional relationships. The fluorescence properties of CPs and the mechanism of detection signal amplification are first discussed, followed by an elucidation of their emerging applications in biological detection. Subsequently, CPs-based imaging systems and therapeutic strategies are illustrated systematically. Finally, recent advancements in utilizing CPs as electroactive materials for bioelectronic devices are also investigated. Moreover, the challenges and outlooks of CPs for precision medicine are discussed. Through this systematic review, it is hoped to highlight the frontier progress of CPs and promote new breakthroughs in fundamental research and clinical transformation.

Synthesis and Insecticidal Activity of Novel Anthranilic Diamide Insecticides Containing Indane and Its Analogs.

Diamide insecticides have always been a hot research topic in the field of pesticides. To further discover new compounds with high activity and safety, indane and its analogs were introduced into chlorantraniliprole, and a battery of chlorfenil derivatives, including indane and its analogs, were designed and prepared for biological testing. Their characterization and verification were carried out through nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Biological detection showed that all the compounds exhibited good insecticidal activity against Mythimna separata. At 0.8 mg/L, the insecticidal activity of compound 8q against Mythimna separata was 80%, which was slightly better than that of chlorantraniliprole. The results of the structure-activity relationship (SAR) analysis indicated that the indane moiety had a significant effect on insecticidal activity, especially in the R-configuration. The results indicated that chlorantraniliprole derivatives containing indane groups could serve as pilot compounds for the further development of new insecticides.

Highly sensitive plasmonic-grating PCF biosensor for cancer cell detection

Highly sensitive biosensor based on D-shaped photonic crystal fiber (PCF) with plasmonic grating is introduced and analyzed. The suggested structure is tested using four different grating structures (rectangular, triangular, circular, or elliptical) on the polished surface of the D-shaped PCF. The sensing operation depends on surface plasmon resonance mechanism where the analyte refractive index (RI) is utilized to control the coupling between the core mode and surface plasmon mode via phase matching phenomenon. Rhodium is employed as a plasmonic material to induce the SPMs. The resonance (i.e., phase matching) wavelength is a function of the analyte RI. The geometrical parameters of the proposed structure are optimized using full vectorial finite element method to enhance the sensor sensitivity. The proposed biosensor can be utilized in the detection of different cancerous Basel, Breast and Cervical cells. The performance of the reported biosensor is investigated in terms of sensitivity, linear response, and fabrication tolerance. The reported biosensor has high sensitivities of 19,750 nm/RIU, 20,428 nm/RIU and 20,041 nm/RIU for the detection of Basel, Breast and Cervical cancer cells, respectively. The presented biosensor is a good candidate for biological sample detection and organic chemical sensing.

Ultrasensitive cancer cell sensing based on tapered optical fiber operating near the dispersion turning point

Cancer cell screening is very important for its treatment and prognosis. The screening techniques are required with high sensitivity and specific recognition. Here, an ultrasensitive tapered optical fiber (TOF) biosensor for cancer cell sensing is proposed. The unique property of the dispersion turning point (DTP) in the TOF is utilized to greatly improve the sensing sensitivity. Combined with numerical calculations, the TOF with the extremely high refractive index (RI) sensitivity (close to 18390 nm/RIU) near the DTP is achieved by precisely controlling the diameter of the TOF. In addition, biotin is used to functionalize the TOF for specific recognition of the biotin-overexpressing cancer cells. The sensitivity and selectivity of the TOF were demonstrated by the detection of the biotin receptor protein (streptavidin) and overexpressed cancer cells (lung epithelial adenocarcinoma cells, A549). The experiment results show that the TOF has a low limit of detection (LOD) for streptavidin and cancer cells, which are 28.73 pM and 49 cells/mL respectively. At the same time, the TOF showed the obvious response to another biotin-overexpressed cancer cell (breast cancer cells, 4T1), but is insensitive to normal cells (gastric mucosa cells, GES-1 and mouse epithelioid fibroblasts cells, L929). We believe that the proposed biosensor which exhibited extremely high sensitivity and good selectivity, will have potential application prospects in the field of chemical and biological detection.

An aptamer-triggered hybridization chain reaction strategy for ultra-sensitive biological nanopore detection of aflatoxin B1

Biological nanopore refers to a type of pore-forming membrane proteins, providing a unique platform for single molecule detection of DNA, RNA, peptide, etc. The direct detection of small molecules, especially of food chemical contaminants by biological nanopore, remains challenging due to their fast translocation dynamics, trace amount, and the interference from the complex food matrix. The effective recognition and signal conversion methods need to be developed. Herein, we employ an aptamer-triggered hybridization chain reaction (AtHCR) strategy for the detection of a mycotoxin, aflatoxin B1 (AFB1) by an α-hemolysin nanopore. In the absence of AFB1, the formed dsDNA polymers in HCR show a low frequency of long-time blockage signals. The presence of AFB1 can inhibit the hybridization chain reaction through the interaction between AFB1 and its aptamer, so the remaining hairpins can easily block the nanopore and induce frequent long-time blockage signals. The results show that the event frequency of long-blockage has a linear relationship with the AFB1 concentration in the range of 6.6 × 10−1–6.6 × 102 pmol/L. The recognition and amplification effect of AtHCR allows nanopore to detect AFB1 at a detection limit of 0.54 pmol/L. Furthermore, the developed AtHCR strategy can help biological nanopore to detect AFB1 in corn sample with satisfactory accuracy. The recognition and amplification effect achieved by coupling AtHCR to biological nanopore offers an enzyme-free single-molecule technology for the rapid detection of food chemical contaminants.

Downregulation of VEGFA accelerates AGEs-mediated nucleus pulposus degeneration through inhibiting protective mitophagy in high glucose environments

Intervertebral disc degeneration (IVDD) contributes largely to low back pain. Recent studies have highlighted the exacerbating role of diabetes mellitus (DM) in IVDD, mainly due to the influence of hyperglycemia (HG) or the accumulation of advanced glycation end products (AGEs). Vascular endothelial growth factor A (VEGFA) newly assumed a distinct impact in nonvascular tissues through mitophagy regulation. However, the combined actions of HG and AGEs on IVDD and the involved role of VEGFA remain unclear. We confirmed the potential relation between VEGFA and DM through bioinformatics and biological specimen detection. Then we observed that AGEs induced nucleus pulposus (NP) cell degeneration by upregulating cellular reactive oxygen species (ROS), and HG further aggravated ROS level through breaking AGEs-induced protective mitophagy. Furthermore, this adverse effect could be strengthened by VEGFA knockdown. Importantly, we identified that the regulation of VEGFA and mitophagy were vital mechanisms in AGEs-HG-induced NP cell degeneration through Parkin/Akt/mTOR and AMPK/mTOR pathway. Additionally, VEGFA overexpression through local injection with lentivirus carrying VEGFA plasmids significantly alleviated NP degeneration and IVDD in STZ-induced diabetes and puncture rat models. In conclusion, the findings first confirmed that VEGFA protects against AGEs-HG-induced IVDD, which may represent a therapeutic strategy for DM-related IVDD.

Inside Front Cover: Advancements in SERS‐based biological detection and its application and perspectives in pancreatic cancer (View 1/2024)

Inside Front Cover: Advancements in SERS‐based biological detection and its application and perspectives in pancreatic cancer (View 1/2024)

A ratiometric fluorescence probe based on dual quantum dots for methyl parathion detection in agricultural products

Methyl parathion (MP) is an organic phosphorus pesticide widely used for pest control of various crops, however, the residual MP can enter the human body and damage the nervous system. Therefore, it is necessary to effectively monitor MP residues. Based on dual-fluorescent quantum dots, this study establishes a ratio fluorescence sensing platform for MP detection, wherein the probe is β-cyclodextrin (β-CD) modified molybdenum disulfide quantum dots (MoS2 QDs) called β-CD-MoS2 QDs. Under alkaline conditions, MP is hydrolyzed into p-nitrophenol (p-NP) and enters the hydrophobic cavity of β-CD, quenching the blue fluorescence of MoS2 QDs whose quenching degree of fluorescence intensity (I400) correlates with the concentration of MP, while the fluorescence intensity (I540) of gQDs remains unchanged and is selected as reference signal. The quantitative detection of MP is conducted by calculating the ratio of fluorescence intensities (I540/I400). The probe detected MP in the range of 0.05–25 ppm with a detection limit of 0.032 ppm which is proved to meet the requirements for biological sample detection according to the methodological validation results. The probe has been successfully applied for the detection of MP in apples and vegetables, confirming its applicability for MP detection in crops.

Artificial intelligence in biology and learning biology: A literature review

Artificial Intelligence (AI) had been developed in various fields of human life. The use of AI brought the world towards a digital transformation that had not been imagined before. One form of AI development in the fields of biology and biology education brought the development of science in both fields far beyond expectations. The use of AI in the fields of biology and biology education had utilized many new methods and discoveries that are beneficial to humans. The purpose of this study was to determine the application of AI in biology and biology learning. The literature review method was used to analyze and synthesize research results from a new perspective. The results of the analysis of various pieces of our literature found various uses of AI. In the field of biology, including AI in the field of biology used for biological data analysis, genetic data analysis, investigation of complex biological phenomena (synthetic biology and system biology), bioinformatics, disease detection, and diagnosis. AI had been utilized in various fields of biological sciences such as medical, agriculture, animal husbandry, and industry for product development and automation in the production process utilizing IoT. There were 24 types of AI utilization in education, especially biology learning, which can be grouped into six groups: personalized and tutoring learning (teaching assistance/tutor), evaluation and assessment, teaching media, enriching learning, virtual classes, and learning aids.

A Contemporary Survey on Deepfake Detection: Datasets, Algorithms, and Challenges

Deepfakes are notorious for their unethical and malicious applications to achieve economic, political, and social reputation goals. Recent years have seen widespread facial forgery, which does not require technical skills. Since the development of generative adversarial networks (GANs) and diffusion models (DMs), deepfake generation has been moving toward better quality. Therefore, it is necessary to find an effective method to detect fake media. This contemporary survey provides a comprehensive overview of several typical facial forgery detection methods proposed from 2019 to 2023. We also analyze and group them into four categories in terms of their feature extraction methods and network architectures: traditional convolutional neural network (CNN)-based detection, CNN backbone with semi-supervised detection, transformer-based detection, and biological signal detection. Furthermore, it summarizes several representative deepfake detection datasets with their advantages and disadvantages. Finally, we evaluate the performance of these detection models with respect to different datasets by comparing their evaluating metrics. Across all experimental results on these state-of-the-art detection models, we find that the accuracy is largely degraded if we utilize cross-dataset evaluation. These results will provide a reference for further research to develop more reliable detection algorithms.

Self-powered photoelectrochemical immunosensing platform for sensitive CEA detection using dual-photoelectrode synergistic signal amplification

Self-powered photoelectrochemical (PEC) sensing, as an emerging sensing mode, can effectively solve the problems such as weak anti-interference ability and poor signal response of individual photoanode or photocathode sensing. In this work, an ITO/Co–CuInS2 photocathode and ITO/WO3@CdS photoanode based self-powered cathodic PEC immunosensor was developed, which integrated dual-photoelectrode to synergistic amplify the signal for highly sensitive and specific detection of carcinoembryonic antigen (CEA). The self-powered PEC sensor could drive electrons transfer through the difference in Fermi levels between the two photoelectrodes without an external bias voltage. The photoanode was introduced to amplify the photoelectric signal, and the photocathode was only designed for the construction of sensing interfaces. The proposed sensor quantitatively determined the target CEA with the detection limit of 0.23 pg/mL and a linear correlation confine of 0.1 pg/mL ∼100 ng/mL. The constructed immunosensing platform exhibited high sensitivity, satisfactory stability and great biological detection selectivity, providing a feasible and effective strategy for the manufacture of new self-powered sensors in high-performance PEC bioanalytical applications.

Object Detection Model for Marine Organisms Based on Faster R-CNN

With the development of marine resources, image-based biological target detection technology has gradually become the core method of marine ecological monitoring. This paper adopts Faster R-CNN technology, combined with two deep learning models, VGG and ResNet50, to improve the efficiency of target detection and recognition of underwater organisms. By combining large-scale annotated seabed image datasets for training, accurate localization and recognition of biological targets in images can be achieved. Compared to ResNet50, VGG performs better in complex seabed environments, with its mAP 1.75% higher than ResNet50, indicating higher detection accuracy and robustness. Besides, this study provides a practical and feasible solution for underwater ecological monitoring, verifying the excellent performance of ResNet50 in marine biological target detection, and providing an important and reliable support tool for deep-sea scientific research and ecological protection.

Electrokinetic ion transport of viscoelastic fluids in a pH-regulated nanochannel

The objects of nanofluidics-based biological detection are usually viscoelastic fluids, and the rheological properties of viscoelastic fluids can have complex effects on electroosmotic flow and electrokinetic ion transport in nanochannels. However, researchers have mainly focused on Newtonian fluids. In this study, numerical simulations were performed on the electrokinetic ion transport of viscoelastic fluids in a pH-regulated nanochannel. The Oldroyd-B model is used to describe the behavior of the polyacrylamide (PAM) solution, and the Poisson-Nernst-Planck model is used to describe the potential and ion concentration in the electrolyte solution. Compared with the Newtonian fluid, at pH = 8, the PAM solution of cp = 500 ppm has a larger region of low ion concentration in front of the nanochannel entrance and has a larger region of high ion concentration behind the nanochannel exit. When the pH is increased to 8, the surface charge density |σw| increases sharply, which is about 5 times of that at pH = 6. At pH = 8, cKCl = 20 mM, and cp = 500 ppm, two distinct vortices appear behind the nanochannel exit, and rotate in opposite directions.