Narrow Results

Infectious diseases are illnesses caused by pathogenic microorganisms, including viruses, bacteria, fungi, and parasites. These diseases can be transmitted from one individual to another, as well as through contaminated food, water, and insect bites, infectious agents invade the body, multiply, and disrupt normal bodily functions, leading to various health issues. However, due to antimicrobial resistance, the need to develop nanoenabled medicine gained significant attention recently. The management of infectious diseases using carbon nanotubes (CNTs) is an emerging field that leverages the unique properties of these nanostructures for enhanced drug delivery and therapeutic applications. Therefore, this review explores the transformative potential of CNTs in the diagnosis, prevention, and treatment of infectious diseases. As global health challenges escalate due to emerging pathogens and increasing drug resistance, the need for innovative solutions becomes critical. Moreover, the review systematically examines the unique properties of CNTs, including their mechanical, thermal, and electrical characteristics, that make them suitable for various biomedical applications. Further, the review highlights recent advancements in CNTs-based technologies, focusing on their roles in biosensing, drug deliver, and antiviral agents. Furthermore, the review also discusses how CNTs enhance the sensitivity and specificity of diagnostic tools, enabling rapid detection of infectious agents. Additionally, the multifunctional capabilities of CNTs in therapeutic applications, such as targeted drug delivery and pathogen inactivation, are also discussed. Challenges related to the clinical translation of CNTs technologies, including safety, biocompatibility, and regulatory concerns, are critically analyzed. In addition, the review concludes with clinical data by emphasizing the need for interdisciplinary collaboration to harness the full potential of CNTs in the management of infectious diseases, paving the way for future research and development in this promising field.

Vertically aligned carbon nanofibers (VACNFs) have recently become an important tool for biosensor design. Carbon nanofibers (CNF) have excellent conductive and structural properties with many irregularities and defect sites in addition to exposed carboxyl groups throughout their surfaces. These properties allow a better immobilization matrix compared to carbon nanotubes and offer better resolution when compared with the FET-based biosensors. VACNFs can be deterministically grown on silicon substrates allowing optimization of the structures for various biosensor applications. Two VACNF electrode architectures have been employed in this study and a comparison of their performances has been made in terms of sensitivity, sensing limitations, dynamic range, and response time. The usage of VACNF platform as a glucose sensor has been verified in this study by selecting an optimum architecture based on the VACNF forest density.

The structural and material properties of carbon based sensors have spurred their use in biosensing applications. Carbon electrodes are advantageous for electrochemical sensors due to their increased electroactive surface areas, enhanced electron transfer, and increased adsorption of target molecules. The bonding properties of carbon allows it to form a variety of crystal structures. This paper performs a comparative review of carbon nanostructures for electrochemical sensing applications. The review specifically compares carbon nanotubes (CNT), carbon nanofibers (CNF), and carbon nanospikes (CNS). These carbon nanostructures possess defect sites and oxygen functional groups that aid in electron transfer and adsorption processes.

Pathogen diseases cause considerable loses in production of food which impact human health from diverse bacterial/viral infections. Precise spotting and diagnosis of such infectious disease is significant to prevent it from further outbreak issues. Moreover, to detect this kind of diseases at an early stage with highly sensitive and selective basis is necessary to avoid the spread of invasive pathogens. The conventional methods such as ELISA, PCR techniques are currently in use to diagnose bacterial/viral disease with high throughput. Though these diagnostic techniques assist in detect and identify the diseases, there are few modern challenges to be meet in order to make this diagnostic more effective in recent days. In this paper, our designed device consists of Bionanosensor works on nucleic acid-based testing provides result with high specificity and selectivity which is vital for early stage identification in a rapid real-time effective manner

The gate-all-around junctionless field-effect transistor (GAA JL FET)-based biosensor has recently attracted worldwide attention due to its good sensitivity to gate-all-around architecture and overall conduction mechanism. The effect of temperature usually affects the performance of transistors and sensors. Therefore, the impact of temperature on the 3D GAA JL FET-based biosensor has been investigated in this work. The dielectric modulation (DM) approach has been considered for including biomolecules. Consequently, the main proprieties of this biosensor have been investigated by ranging the temperature from 77K to 400K. The simulated results showed that the on-state current lowers as the temperature rises, but the off-state current increases. The off-current variation concerning the temperature is higher than the on-current change. Also, this type of biosensor appears to have a finer threshold voltage. Furthermore, the obtained results reveal that the current sensitivity is increased when ranging from temperature from 200K to 400K, and deteriorates for lower temperature values, like 100K and 77K. In addition, the GAA JL FET-based biosensor is more reliable for the detection of neutral biomolecules at high temperatures.

This paper presents the characterization and testing of electrochemical sensor using microfluidic system. Various geometric patterns were laser cut into the platinum working electrode of a biosensor. In this work, a microfluidic chamber was designed that allows phosphate buffer solution (PBS) to flow across the sensor, using a peristaltic pump, while varying the concentration of hydrogen peroxide. The amperometric characterization of the electrochemical sensor with 25, 50, 75, and 100$\mu$m perforation and 75$\mu$m spacing showed the highest sensitivity. This result was to be expected the purpose of patterning the sensors was to provide a 3-dimensional structure to the planar electrode in order for the enzyme, glucose oxidase, to be immobilized. Future work will include selecting one of the patterns for immobilization of glucose oxidase allowing us to realize a fully functional glucose sensor.

The facile entrapment of oxidoreductase enzymes within polyaniline polymer films by inducing hydrophobic collapse using phosphate buffered saline (PBS) has been shown to be a cost-effective method for fabricating organic biosensors. Here, we use fluorescence anisotropy measurements to verify enzyme immobilization and subsequent electron donation to the polymer matrix, both prerequisites for an effective biosensor. Specifically, we measure a three order of magnitude decrease in the ratio of the fluorescence to rotational lifetimes. In addition, the observed fluorescence antiquenching supports the previously proposed model that the polymer chain assumes a severely coiled conformation when exposed to PBS. These results help to empirically reinforce the theoretical basis previously laid out for this biosensing platform.

Dopamine (DA) is a crucial molecule for the central nervous system, and the ability to detect it in samples containing molecules such as Ascorbic Acid (AA) and Uric Acid (UA) could facilitate early diagnosis of related disorders. In this work, the interaction of DA, UA, and AA with InBi and Graphene (GR) monolayers under charging was investigated using Density Functional Theory (DFT) calculations with van der Waals (vdW) correction and nonequilibrium Green’s function method for the first time. According to our calculations, the most influential factor in the interaction was observed to arise from the $\pi$–$\pi$ and $\pi$–O interaction between molecules and surfaces. It has been concluded that InBi is a better adsorbent than GR for DA, AA, and UA, where the adsorption energies from the highest to lowest were found as $\mathrm{\text{UA}}>\mathrm{\text{AA}}>\mathrm{\text{DA}}$. Furthermore, the charge transfers between molecules and surfaces were investigated, and it was demonstrated that the molecules on GR act as charge acceptors. In contrast, for InBi–molecule systems, electronic drift from molecules to the InBi surface was observed. The Partial Density of States (P-DOS) plots were examined, and the results were discussed in detail. The consequences of adding/removing charges to/from the systems were also examined, and it was shown that removing $Q=2$e/cell from the GR–molecule systems effectively detected DA molecules from the others. Charging also broke the topological state of InBi, leading to semiconductor to metal, except for the $Q=-2$e/cell case. Finally, the changes in transmittance due to adsorption were simulated, and our results show that InBi is a possible candidate for DA sequencing biosensor applications compared to GR. The findings of this work provide a theoretical framework for the development and creation of highly precise biodevices and biosensors.

In this paper, a simple two-dimensional (2D) photonic crystal (PhC) plus-shaped resonator is suggested to detect different cancer cells as well as urine glucose. A novel biosensor design is presented that features a plus-shaped PhC resonator capable of detecting cancerous cells in human skin, cervix, blood, adrenal glands and breast, as well as detecting glucose levels in human urine to diagnose the likelihood of diabetes. Our biosensor boasts of an impressive quality factor of 307 for cancerous skin cells and 670.6 for glucose concentration in the blood. In addition, the device offers a maximum sensitivity of 750nm/RIU for detecting various cancerous cells and 2420nm/RIU for glucose in human urine. By positioning the resonator and the waveguide in a way that enables light to resonate in the middle of the structure and pass to the output terminal, we were able to focus on the absorption rate rather than the transmission. As a result, the maximum glucose and cancerous cell absorption rates reach 87.1% and 89.8%, respectively. Our unique yet simple sensor structure offers exciting new possibilities for detecting different cancerous cells and glucose concentrations, while the impressive sensitivity and quality factor make it an exceptional candidate for a wide range of biosensing applications.

This paper presents the proposed inductorless RF-Symmetrical DC energy harvester for low power biosensor transceiver. It is designed to benefit from the symmetrical power supply to reduce the low noise amplifier power consumption of the biosensor reception part. Several techniques are used in this work to design a high efficiency RF-DC harvester with minimum number of stages as: the use of the diode-connected CMOS transistor which its bulk is related to its drain to minimize the leakage current and to reduce the threshold voltage for more energy harvesting, and the use of the Greinacher voltage multiplier to decrease the effect of the voltage drop between the drain and the source of the CMOS transistor. The impedance matching circuit between the antenna and the energy converter is designed without inductors to gain more power and space. Conceived under the 0.18$\mu$m TSMC MOS technology with only four stages, the harvester simulation results show a high efficiency of 56% which the minimal voluntary received power is about 0dBm required by the IEEE 802.15.4 standard. The symmetrical DC output voltage is of 1/$-$1V as expected in the specifications. Therewith, its delivered power is equal to 1mW for storage capacity about 20nF.

The tunnel field-effect transistor (TFET) has emerged as a promising device for biosensing applications due to band-to-band tunneling (BTBT) operation mechanism and a steep subthreshold swing. In this paper, an electrically doped cavity on source junctionless tunnel field-effect transistor (ED-CS-JLTFET)-based biosensor is proposed for label-free detection of biomolecules. In the proposed model, the electrically doped concept is enabled to reduce fabrication complexity and cost. In order to create a nano-cavity at the source region, some portion of the dielectric oxide of the polarity gate terminal is etched away. To perceive the presence of biomolecules, two important properties of biomolecules, such as dielectric constant and charge density, are incorporated throughout the simulation. The sensing performance of the proposed ED-CS-JLTFET-based biosensor has been analyzed in terms of transfer characteristics, threshold voltage and subthreshold swing. In addition, the sensitivity of the proposed biosensor has also been analyzed with respect to different fill factors (FFs), varying nano-cavity dimension and work-function of the control gate. It is found from the simulated results that the proposed ED-CS-JLTFET-based biosensor offers higher current sensitivities with neutral, positively charged and negatively charged biomolecules of $3.01\times 10^{11}$ (at k$=12$), $9.51\times 10^7$ (at $k=6$ and $\rho =2\times 10^{12}$ C$\cdot$cm${}^{-2}$) and $4.04\times 10^{10}$ (at k$=6$ and $\rho =-2\times 10^{12}$ C$\cdot$cm${}^{-2}$), respectively.

The tunneling field effect transistor (TFET) is a viable candidate for designing a highly sensitive biosensor. In this work, a doping-less Z-shaped dielectrically modulated charge plasma TFET (CPTFET) structure with misaligned cavity region on channel and source has been proposed for label-free biosensing applications. To design the device, charge plasma technique has been employed, where appropriate metal workfunction is used over intrinsic silicon to create n${}^{+}$ drain and p${}^{+}$source regions. The charge plasma approach reduces thermal budget, random dopant fluctuation (RDF) and steps required for fabrication. The Z-shaped CPTFET includes the advantage of abrupt profile of doping at source-channel (tunneling) junction. Because cavities are created in source and gate oxide region, the abrupt doping profile suppresses ambipolar behavior and improves sensitivity. The performance of the proposed device for both charged and neutral biomolecules in terms of electric field, band energy, transfer characteristics, $I_{\mathrm{\text{ON}}}/I_{\mathrm{\text{OFF}}}$ ratio and subthreshold swing (SS) has been examined. The response of other parameters like cavity thickness and cavity length on ON current has been analyzed using the Silvaco ATLAS device simulator.

The fabrication complexity and cost associated with nanoscale devices are major concerns. Therefore, to address these challenges, we have introduced a mole fraction-based approach for the sensitivity analysis of a dual material control gate cavity on a source electrically doped polarity-controlled tunnel field effect transistor (DMCG-CS-ED-PC-TFET)-based biosensor for label-free detection of biomolecule species. For this purpose, a polarity bias (electrically doped) of PG-$1=+1.2$ V and PG-$2=-1.2$ V is applied for the formation of n+ drain and p+ source regions, respectively, over the thin silicon body. The proposed device structure overcomes the random dopant fluctuation issues, thereby avoiding thermal budget and fabrication complexity as compared to the conventional TFET. Moreover, the nanogap cavity is created by etching the appropriate portion at the source side oxide layer. Furthermore, we have applied a dual metal work function (M1 and M2) at the gate electrode along with hetero material ${\mathrm{\text{Si}}}_{1-X}{\mathrm{\text{Ge}}}_X$ at the source side region to improve the sensitivity of the device by varying the mole fraction value (X). The performance of the proposed device has been evaluated in terms of variations in carrier concentration profile, electric field variation, energy band diagram, transfer ($I_{\mathrm{\text{DS}}}-V_{\mathrm{\text{GS}}}$) characteristics and the sensitivity in terms of drain current (I${}_{\mathrm{\text{DS}}}$), ON-state current (I${}_{\mathrm{\text{ON}}}$) and switching ratio (I${}_{\mathrm{\text{ON}}}$/I${}_{\mathrm{\text{OFF}}}$). Furthermore, the sensitivity of the proposed device biosensor has been investigated by considering nanocavity dimensions, practical challenges such as various fill factors, and various step profiles generated from steric hindrance. For this purpose, different neutral biomolecules such as Biotin ($k=2.63$), APTES ($k=3.57$), Keratin ($k=8$), Ferrocytochrome C ($k=4.7$) and Gelatin ($k=12$) have been considered in the etched nanocavity region. Additionally, charged biomolecules with positive (negative) charge densities at the oxide semiconductor interface below the nanocavity region have been incorporated to assess the performance of the proposed device using the Silvaco ATLAS device simulator. In this analysis, the proposed biosensor achieves a drain current sensitivity of $5.65\times 10^{10}$ for neutral biomolecules ($k=12$), $6.2\times 10^{10}$ for $\rho$ = $1\times 10^{12}$ cm${}^{-2}$ with $k=12$ and $1.2\times 10^{11}$ for $\rho$ = $-1\times 10^{12}$ cm${}^{-2}$ and $k=12$. Finally, the performance of the proposed biosensor, DMCG-CS-ED-PC-TFET, exhibits higher sensitivity compared to various existing TFET-based biosensors. Hence, the proposed biosensor exhibits the potential candidate for the development of future sensing bio-equipment.

This paper proposes a novel polarity-control junctionless tunnel field-effect transistor (PC-JL-TFET)-based biosensor for the label-free detection of biomolecule species in efficient ways. Unlike conventional designs, the polarity-control concept induces the generation of drain (n${}^{+}$) and source (p${}^{+}$) regions inside the proposed structure when a bias of $\mp 1.2$ V is applied at the polarity gates-1/2 (PG-1/2), to form a conventional TFET. To capture the biomolecules, a nano-cavity is created within the source region’s dielectric oxide toward the tunneling interface. The presence of biomolecules is electronically detected based on either solely the dielectric constant (neutral biomolecules) or the combination of charge density and dielectric constant (charged biomolecules). The proposed device can perform label-free recognition of biomolecules such as Uricase, Keratin, Biotin, Streptavidin and so on. To investigate the sensing performance of the proposed biosensor, significant biosensing metrics such as the electric field, energy band diagram, tunneling current, subthreshold slope, $I_{\mathrm{\text{ON}}}/I_{\mathrm{\text{OFF}}}$ ratio and threshold voltage have been studied. The proposed PC-JL-TFET biosensor achieves a maximum sensitivity of $5.31\times 10^{10}$ for neutral biomolecules with a dielectric constant of 12 and $1.11\times 10^{10}$ for negatively charged biomolecules $(-1\times 10^{12}{\mathrm{\text{C/cm}}}^2)$ with a dielectric constant of 8. The proposed biosensor’s selectivity, linearity and temperature-based analysis have also been evaluated for different biomolecules. Additionally, real-time practical scenarios, such as partially filled nano-cavities and the random position of biomolecules in the nano-cavity-based analysis, have also been incorporated.

A sensitive and fast sensor for quantitative detection of organophosphorus pesticides (OPs) is obtained using acetylcholinesterase (AChE) biosensor based on graphene oxide (GO)–chitosan (CS) composite film. This new biosensor is prepared via depositing GO–CS composite film on glassy carbon electrode (GCE) and then assembling AChE on the composite film. The GO–CS composite film shows an excellent biocompatibility with AChE and enhances immobilization efficiency of AChE. GO homogeneously disperses in the GO–CS composite films and exhibits excellent electrocatalytic activity to thiocholine oxidation, which is from acetylthiocholine catalyzed by AChE. The results show that the inhibition of carbaryl/trichlorfon on AChE activity is proportional to the concentration of carbaryl/trichlorfon. The detection of linear range for carbaryl is from 10nM to 100nM and the correlation coefficients of 0.993. The detection limit for carbaryl is calculated to be about 2.5nM. In addition, the detection of linear range for trichlorfon is from 10nM to 60nM and the correlation coefficients of 0.994. The detection limit for trichlorfon is calculated to be about 1.2nM. This biosensor provides a new promising tool for trace organophosphorus pesticide detection.

We describe experiments with surface plasmon polaritons excited by a laser beam in the Kretschmann configuration that are diffracted by a periodic pattern at the metal/dielectric interface. This suggested technique has become a novel sensing principle with particular potential for bio-affinity studies. It is demonstrated that the optical field enhancements associated with the resonant excitation of surface plasmons directly translate into a sensitivity gain. A few characteristic features of the obtained diffraction patterns, e.g., the quadratic increase of the intensity diffracted into higher order spots with the increase of the grating amplitude, are discussed. Moreover, it is shown that the basic mechanism of the signal generation leads to a so-called self-referencing of the sensor which makes it largely insensitive to variations in temperature or refractive index fluctuations of the analyte solution.

Shenzhen biotech companies building the world’s largest cell bank in Guizhou.

China’s cancer researcher shares 2018’s Sjoberg Prize of Sweden.

Breakthrough may help with earlier detection of heart attacks and cancer.

New dialyzer to isolate bacteria from unprocessed blood.

Chinese scientists develop new protocols for DNA-free genome editing in wheat.

Synthesized herbs to treat cardio-cerebrovascular disease.

Chinese scientists find antidote to centipede venom.

Grünenthal and Mundipharma enter commercial partnership in China.

Tencent and Medopad to cooperate on medical AI.

Majority of oncology clinical trials in China failed to meet enrolment targets.

WuXi STA and Regulus announce microRNA development and manufacturing collaboration.

Fracture is one of the most important health problems in people’s life. Millions of people have fractures every year. However, there is no unified standard for fracture healing in the clinic. Most definitions of complete fracture healing are subjective evaluations based on X-ray films. However, it is not reliable to evaluate the biomechanical strength of bone according to the number of callus on X-ray, and the imaging time of callus lags behind the actual callus, which is not conducive to the evaluation of early fracture healing time. In addition, although more and more fracture patients have achieved imaging healing after injury, the bone quality and bone strength of the whole body and local fracture have not returned to the normal level, and the probability of re-fracture has increased significantly, which has brought great pain to their families. Fracture healing is affected by many factors, such as age, fracture site, whether to fix the fracture site, and osteoporosis. Therefore, when evaluating the fracture healing status of patients, we should not only evaluate whether the fracture is healed but also evaluate its healing. By analyzing the previous research methods of fracture healing, in this paper, we systematically summarize the evaluation methods of fracture healing from the perspectives of computer tomography, ultrasound, bone density, biosensors, and biomechanics by analyzing previous research methods of fracture healing, aiming to provide reference for researchers in related fields.

Both the determinations of glutamate pyruvate transaminase and creatine kinase were related to low signal detection. Novel amperometric biosensors for the detection of glutamate pyruvate transaminase and creatine kinase were constructed by simple gold two-electrode. The electrode for the determination of GPT was modified with nanoporous platinum-black particles and the electrode for the determination of creatine kinase was modified with porous hydrophilic carboxyl-methyl cellulose. The reagent was added on the electrode surface with nanoporous structure. Ferricyanide was used as electron mediator to detect glutamate pyruvate transaminase. Biosensors appeared good electrochemical characteristics for the rapid measurements of glutamate pyruvate transaminase and creatine kinase, respectively. The sensors showed linear response to aminotransferase and creatine kinase in the concentration range 50–2500 U/L and 50–2000 U/L, showing correlation coefficients 0.991 and 0.995, respectively.

A novel biosensor for dopamine (DA) detection was fabricated using TiO₂ nanotube and Au/TiO₂ nanotube films on glassy carbon electrode (GCE). The Au/TiO₂ nanotubes on electrode showed better electrocatalytic activity towards the detection of DA which was attributed to its excellent electron conductive network. The biosensor elicited sensitivity of 22 nA/μM with a linearity of detection localized in the concentration range from 5–120 μM with correlation coefficient of 0.99. The detection limit of DA for the Au/TiO₂ nanotube biosensor was found to be ~3 μM (S/N = 3). In addition, the fabricated sensor showed good anti-interference capability towards biological compounds such as ascorbic acid and uric acid. In conclusion, Au/TiO₂ nanotube biosensor exhibits excellent catalytic activity, selectivity and simplicity for the detection of dopamine.