Advances made in the field of materials science leads to technological development. Nowadays, composite materials, used in various fields such as engineering, industry, medicine are corrosion resistance and have lightweight and high fatigue strength, and promise faster assembly –they can withstand loads, insulate or conduct heat and electricity, accept or reject magnetic flux, transmit or reflect light, be stable in hostile environments, and possesses all these characteristics cost-effectively and with minimal impact to the environment. The chosen material needs to be compatible with the manufacturing process; because even with the right materials, an incorrect manufacturing process can be disastrous. This study displays the impact of organoclay and/or natural fibers on the performance of polysulfone (PSF) nanocomposite materials for variable applications. First, PSF production and properties are outlined, and then a detailed study of organoclay and its importance as nanofiller in polymer matrices has been investigated, with a special attention to PSF. Properties of natural fibers reinforced variable nanocomposites for wide range of application together with PSF in the form of nanocomposites have also been researched and analyzed. Moreover, the recent research on the hybrid nanocomposite-based clay/natural fiber in the presence of different polymers has been also displayed in details.
Conventional treatments for cancer include surgery chemotherapy and radiotherapy These methods are not necessarily effective in all cancers and each has its own side effects and researchers are now looking for other ways to fight cancer According to studies in this field new methods of cancer treatment include nano drug delivery and hyperthermia using magnetic nanoparticles Studies show that using nano drug delivery knowledge the drug works only in the affected area and does not cause complications in healthy areas of the body By using these methods drugs can be delivered accurately and quickly to target tissues Also in hyperthermia a fluid containing magnetic nanoparticles is injected directly or through the vein system into the target tissue and an alternating magnetic field generated by magnetic coil such as Helmholtz Coil is applied to the target area and the magnetic nanoparticles emit heat The heat produced increases the temperature of the tissue and destroys the desired cells by increasing the temperature above deg C In this article we survey the Helmholtz coil and designing and manufacturing a new coil to create a homogeneous magnetic field and build a magnetic field measuring sensor to measure the magnetic field flux produced by the new coil nbsp Conventional treatments for cancer include surgery chemotherapy and radiotherapy These methods are not necessarily effective in all cancers and each has its own side effects and researchers are now looking for other ways to fight cancer According to studies in this field new methods of cancer treatment include nano drug delivery and hyperthermia using magnetic nanoparticles Studies show that using nano drug delivery knowledge the drug works only in the affected area and does not cause complications in healthy areas of the body By using these methods drugs can be delivered accurately and quickly to target tissues Also in hyperthermia a fluid containing magnetic nanoparticles is injected directly or through the vein system into the target tissue and an alternating magnetic field generated by magnetic coil such as Helmholtz Coil is applied to the target area and the magnetic nanoparticles emit heat The heat produced increases the temperature of the tissue and destroys the desired cells by increasing the temperature above deg C In this article we survey the Helmholtz coil and designing and manufacturing a new coil to create a homogeneous magnetic field and build a magnetic field measuring sensor to measure the magnetic field flux produced by the new coil
The development of various new kinds of sensors for the accurate detection of biomarkers in biological fluids and environmental samples are of greatest importance for the early diagnosis of diseases and to avoid the contamination of environment through pollutants, toxic and biohazardous materials. Sensitivity limits of biosensor have increased due to developments of new biological methods like tagging of fluorescence molecule with nanomaterials. Moreover, usage of peptide arrays, aptamers, antibodies, nucleotides and molecule fixed polymers, facilitate to improve advanced biosensors over conventional approaches. Several biosensors ranging from nanomaterials, polymers to microbes have broader potential applications. Generally, biosensor has been organized into several categories containing diverse sensing arrangements such as mechanical, optical and electrical transducers and modern biosensors use micro- and nanofabrication tools, as either label-free or labeled. This review provides an overview of recent developments and applications of biosensors in the fields of biomedical sciences and environmental monitoring, along with the better detection limit and improved sensitivity of the biosensors.
A novel sensing system has been designed for the detection of copper ions (Cu2+). It is based on the quenched fluorescence signal of carbon nanoparticles (CNPs), which were carbonization from polyvinylpyrrolidone and L-cysteine. Cu2+ can be captured by the nitrogen and sulfur groups of the CNPs to form an absorbent complex at the surface of CNPs; this results in strong quenching of the CNPs’ fluorescence via a fast metal-to-ligand binding affinity. The resulting water-soluble CNPs also exhibited a quantum yield of 7.6%, with favorable photoluminescent properties and good photostability. Importantly, the fluorescence intensities of the CNPs were quite stable in high ionic strength (up to 1.0 M NaCl) and over a broad range of pH levels (2.0–12.0). This facile method can therefore develop a sensor that offers rapid, reliable, and selective detection of Cu2+ with a detection limit as low as 0.15 μM and a dynamic range of 0.5–7.0 μM (R2 = 0.980). This sensing system was also successfully applied to determine Cu2+ in a lake water sample with satisfactory recovery levels.
A real-time detection and monitoring (RTDM) of microbial contamination on solid surfaces is mandatory in a range of security, safety and bio-medical applications where surfaces are exposed to accidental, natural or intentional microbial contamination. This work presents a new device, the BC-Sense, which allows a rapid and user-friendly RTDM of microbial contamination on various surfaces while assessing the decontamination kinetics and degree of cleanliness. The BC-Sense LIDAR (Light Detection and Ranging) device uses the Laser-Induced Fluorescence (LIF) method based on dual wavelength sensing with multispectral pattern recognition system to rapidly detect microbial contamination on a solid surface. Microbial simulants (bacteria, bacterial spores, fungal conidia and virus) were spread at varying concentrations on a panel of solid surfaces which were assessed by BC-Sense. The spectra of dead and living E. coli showed differences at various sensing wavelengths. The limit of detection (LoD) of E. coli and MS2 virus was 2.9 × 104 and 9.5 × 104 PFU and CFU/cm2, respectively. Random samples (n=200) tested against a training dataset (n=800) were optimally discriminated for contamination versus background with a threshold of predicted response (PR) >0.55 and 10 min with spores and E. coli.
Single molecule detection is of vital importance for fundamental biotechnology research and practical applications. Among the numerous single molecule detection techniques, solid-state nanopores ha ...
The fiber-optic biosensor with encapsuled bioreporters use a special optical element (OE) from pure silica with an active layer contents bioluminescent bioreporters was developed as a real in-situ detector for on-line measurement in remote localities. The active layer of biosensor contents bioluminescent bioreporters – genetic modified cells, which are sensitive to its surrounding environment-immobilized in silica matrix on the end of OE. Bioreporters are able to react by emission of visible light (≈500 nm) – bioluminiscence reaction (BL) – in presence of specific analyte. The genetic modified bacterial stain Pseudomonas putida TVA8 was chosen as biorecognition part of biosensor producing BL in the presence of benzene, toluene, ethylbenzene and xylens (BTEX). Very low level of BL signal was detected by high-sensitive photon-counter. The sensitivity of biosensor depends on a value of detected BL and it can be very low. The signal is also affected by number of cells (light sources) immobilized into the active layer and transmission through OE. Mathematical model of OE shape was developed based on geometric optics. The numerical model is built around the MATLAB scripting language. Simulation of ray transmission was calculated for OE with different shape.
