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Magnetite nanoparticles (NPs) were synthesized using a cost-effective co-precipitation method. Magnetite NPs were encapsulated with silica via the modified Stober Method. Tetra ethyl ortho silicate (TEOS) was hydrolyzed and condensed with ethanol and H₂O solution. Stable and biocompatible NPs were synthesized for biomedical applications such as bioseparation. This study expresses the NPs that can potentially be used in the bioseparation of toxic protein isolations and targeted drug delivery. X-ray diffraction verified the phase pattern having crystals like Fd-3m cubic space. Scanning electron microscopy (SEM) images identified the spherical-shaped NPs having size ranges from 15nm to 30nm for magnetite NPs and 20–40nm for silica-coated magnetite NPs. Fourier transform infrared spectroscopy (FTIR) confirmed the bond spectrum peak at 549${\text{cm}}^{-1}$ and 562${\text{cm}}^{-1}$ for magnetite NPs and silica-coated magnetite NPs, respectively. UV–Visible analysis observed the band absorptions above 250nm for magnetite and above 300nm for silica-coated magnetite NPs. This research suggests an easy way to use silica-coated Magnetite NPs for bioseparation at room temperature.

In this paper we propose a method for increasing precision and reliability of elasticity analysis in complicated burn scar cases. The need for a technique that would help physicians by objectively assessing elastic properties of scars, motivated our original algorithm. This algorithm successfully employed active contours for tracking and finite element models for strain analysis. However, the previous approach considered only one normal area and one abnormal area within the region of interest, and scar shapes which were somewhat simplified. Most burn scars have rather complicated shapes and may include multiple regions with different elastic properties. Hence, we need a method capable of adequately addressing these characteristics. The new method can split the region into more than two localities with different material properties, select and quantify abnormal areas, and apply different forces if it is necessary for a better shape description of the scar. The method also demonstrates the application of scale and mesh refinement techniques in this important domain. It is accomplished by increasing the number of Finite Element Method (FEM) areas as well as the number of elements within the area.

The method is successfully applied to elastic materials and real burn scar cases. We demonstrate all of the proposed techniques and investigate the behavior of elasticity function in a 3-D space. Recovered properties of elastic materials are compared with those obtained by a conventional mechanics-based approach. Scar ratings achieved with the method are correlated against the judgments of physicians.

A novel coplanar waveguide (CPW) fed circular slot antennas are proposed for industrial, scientific and medical (ISM) band (2.4–2.48 GHz) applications. To make the designed antenna suitable for implantation, it is embedded in biocompatible Al2O3 ceramic substrate. The antenna was simulated by immersing it in a phantom liquid, imitating the electrical properties of the human muscle tissue. A study of the sensitivity of the antenna performance as a function of the dielectric parameters of the environment in which it is immersed was performed. Simulations in various dimensions state demonstrate that the antenna covers the complete ISM band. The demonstration among the design EM characteristics of the antenna is presented by current distributions.

This paper presents the design and realization of a low-noise, low-power, wide dynamic range CMOS logarithmic amplifier for biomedical applications. The proposed amplifier is based on the true piecewise linear function by using progressive-compression parallel-summation architecture. A DC offset cancellation feedback loop is used to prevent output saturation and deteriorated input sensitivity from inherent DC offset voltages. The proposed logarithmic amplifier was designed and fabricated in a standard 0.18$\mu$m CMOS technology. The prototype chip includes six limiting amplifier stages and an on-chip bias generator, occupying a die area of 0.027mm². The overall circuit consumes 9.75$\mu$W from a single 1.5V power supply voltage. Measured results showed that the prototype logarithmic amplifier exhibited an 80dB input dynamic range (from 10$\mu$V to 100mV), a bandwidth of 4Hz–10kHz, and a total input-referred noise of 5.52$\mu$V.

A novel capacitance multiplier is proposed to implement an ultra-low-frequency filter for physiological signal processing in biomedical applications. With the proposed multiplier, a simple first-order low-pass filter achieves a $-$3-dB frequency of 33.4μHz with a 1-pF capacitance and a 20k$\mathrm{\Omega }$ resistance. This corresponds to a multiplication factor of as large as $2.4\times 10^{11}$. By changing the controlling terminal, the $-$3-dB frequency can be tuned in a wide range of 33.4μHz–6.3kHz.

This paper presents a low power temperature compensated CMOS ring oscillator for biomedical applications across a wide temperature range. The proposed circuit deploys an IPTAT (inversely proportional to absolute temperature) bias current by generating an adaptive control voltage in each stage of the oscillator to compensate the overall oscillator’s temperature coefficient (TC). Simulations using TSMC 0.18$\mu$m CMOS technology show that this configuration can achieve a frequency variation less than 0.25%, leading to an average frequency drift of 20.83ppm/^∘C.

Monte Carlo simulations have also been performed and demonstrate a 3$\sigma$ deviation of about 2.15%. The power dissipated by the proposed circuit is only 8.48mW at 25^∘C.

This paper presents a complementary split-ring resonator (CSRR) loaded coplanar waveguide (CPW) fed with a circular shape, miniaturized diamond slot planar monopole antenna. The proposed antenna for healthcare monitoring biomedical applications uses the industrial medical and scientific band. The antenna design and development to implant the human phantom are proposed. The primary goal of this work is to continuously monitor the patient’s ability to detect abnormal conditions as soon as possible as a result of improvements in quality of life. In this case, an antenna design methodology must prioritize features such as miniaturization, increased gain and bandwidth, and biocompatibility. Simulated and measured antenna characteristics for biomedical applications are performed at ISM Band frequency.

In many integrated circuit applications, where large passive resistors are prohibited, a tunable active resistor is necessary. This paper presents a compact and wide-range voltage-controlled grounded resistor that employs MOS transistors only. The design’s foundation is an active adjustable resistor that controls the NMOS transistor’s mode of operation. The proposed design is implemented using 0.18$\mu$m TSMC CMOS technology and is validated through post-layout simulations conducted in the Cadence Virtuoso environment. Furthermore, a tunable high-pass filter utilizing the proposed active resistor is also shown. The circuit is powered by 1.5V DC. According to the simulation findings, the resistance varies between 33k $\mathrm{\Omega }$ and 36G $\mathrm{\Omega }$, for an input voltage range $-$0.7–0.6v.

Biocompatible polyacrylamide gels are widely required for the development of mechanically “soft” magnetic material for the purposes of different biomedical applications. In this work, ferrogels were synthesized by radical polymerization of acrylamide in a stable aqueous suspension of magnetic maghemite $\gamma$-Fe${}_{2.04}$O${}_{2.96}$ nanoparticles (MNPs) with the median value in diameter of 11.4nm fabricated by laser target evaporation. Gel network density was set to 1:100, the concentrations of embedded MNPs were fixed at 0.00%, 0.25%, 0.50%, 0.75% or 1.0% by weight. Ferrogels’ Young’s modulus and affinity to the human dermal fibroblasts adhesiveness were tested. To estimate the cells adhesive activity to gels, the adhesion index was calculated as the number of adhered cells divided by the number of cells sown and multiplied by 100%. The gradual increase of MNPs concentration in the gel network resulted in the significant increase of ferrogel’s Young’s modulus and cells adhesion activity. In particular, at the MNPs concentration of 0.25%, the modulus and the adhesion index were equal to $\sim$30kPa and $\sim$90%, correspondingly. The adhesion index at highest MNPs concentration of 1.0% was close to 100% and modulus to $\sim$40kPa. The increase of cells adhesiveness rise with MNPs concentration closely correlated with the direct impact of MNPs on the gel stiffness.

Current cell tags using dyes lose their luminescence quickly and are not suitable for optical barcoding. Semiconductor quantum dots (QDs), on the other hand, can be engineered to emit different wavelengths, thus permitting tagging of various cells at the same time. Core/shell luminescent quantum dots, cadmium selenide (CdSe) and zinc sulphide (ZnS), were synthesized and incorporated into polystyrene (PS) particles grafted with carboxyl groups using microemulsion polymerization method. Highly luminescent monodispersed PS particles with diameters from 30 nm to 50 nm were chosen for subsequent surface modification. Two series of surface modifications were carried out with PS particles. One was modified with poly(L-Lysine) (PLL), polyethylenimine (PEI), Poly(Ethylene Glycol) (PEG) and folic acid (FA) side chains in sequence through chemical bonding. Another was conjugated with PEG and FA in sequence. The folic acid side chains can enter target cells via folate receptors and assisted in the uptake of the luminescent particles into the cells. This property allows them to be used as fluorescent labels for marking their ingress into cells and also for a cornucopia of biomedical applications.

A new nano-hybrid material prepared by physical mixing of the components was used in biomedical applications where three samples of the prepared materials were used to determine the best composition as an antibacterial and anticancer agent in addition to its use as an antifungal agent. In the case of antimicrobials, two types of bacteria were used: Staphylococcus aureus and Escherichia coli and one type of fungus was used: Candida albicans. The area of inhibition was calculated after using the hybrid material of 2.5% titanium oxide with iron oxide, which gave better results than pure iron oxide and that mixed with 5% titanium dioxide.

The structural, morphology, and optical properties of a new hybrid structure prepared from CuO nanoparticles embedded in a Fe₂O₃–PVA composite matrix were investigated in this work. Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), absorption and transmission spectra, and Fourier transform infrared spectroscopy (FT-IR) were all used to analyze the prepared materials. Crystallography information revealed the presence of CuO that did not affect the crystal structure of PVA–Fe₂O₃. The prepared composites revealed strong absorption in the range of 440–570 nm. It was observed that the highest absorption of these composites gradually shifted to the shorter wavelength region with the presence of CuO. PVA–Fe₂O₃ is highly transparent, with a transmittance of around 85% in the range of 600–800 nm. After the addition of 5% by weight of CuO nanoparticles, the transmittance of the nanocomposite drops to 75% in the same range of wavelength. The prepared materials were used as anti-cancer cells, and they showed high efficacy to kill tumor cells, especially PVA–Fe₂O₃–CuO at concentration 0.5 $\mu$g/mL.

Currently, the field of nanoscience and nanotechnology has potential advantages in various disciplines of science. Nanomedicine has emerged as a specific application of nanotechnology in health system. The use of nanoscale materials in nanomedicine holds a promising potential for prevention, diagnosis and treatment of several diseases. During the last three decades, carbon nanotubes (CNTs) have stimulated a significant attention worldwide due to their impressive advantages like small size and mass, high surface area-to-volume ratio, easy functionalization, superb physico-mechanical properties, and so on. CNTs have provided multifunctional platforms for biological applications such as bioimaging, biosensing, medical diagnosis, phototherapy, drug and gene delivery, tissue engineering, etc. owing to their innovative and attractive properties. This review presents a comprehensive framework of the unique advantages and up-to-date advanced biomedical applications of CNTs to date, with special emphasis on the recent progress in nanomedicine like phototherapy, drug and gene delivery, and tissue engineering. Besides the applications, an overview of CNTs along with some important methodologies of synthesis is also discussed herewith. Lastly, some major concerns to be challenged and perspectives for the future development of CNTs in the field of biomedical sector are highlighted in this paper which will help to give valuable insights into new research directions.

This review, dedicated to Professor Tomás Torres on the occasion of his 65th birthday, offers an overview of the main achievements in his research career. Having a strong background in organic chemistry, he and his group have constantly devoted much effort to the development of synthetic methods towards novel systems based on phthalocyanines and other porphyrinoid analogues. Not less important, the founding of solid collaborations with other prominent scientists has led to study the physicochemical properties of these $\pi$-conjugated dyes, and to evaluate their potential application in multidisciplinary areas such as self-assembly, nanochemistry, optoelectronics and biomedicine.

Cancer is the second major threat to human health, and more effective cancer therapy strategies are imperative. With the development of nanotechnology, mesoporous silica-based nanoparticles (MSNs) have seen unprecedented development in cancer treatment, such as drug delivery, bioimaging and biosensing. They have received extensive attention because of their easy preparation, adjustable morphology, homogeneous pore structure, high surface areas and good biocompatibility. However, cumulative toxicity for organism caused by the low degradability of MSNs heavily hinders their translation from bench to beside. Enhancing the degradability of MSNs has provided an effective solution to solve this problem. This review aims at summarizing the effective strategies utilized to regulate the degradability of MSNs during the last few years, giving a complete overview on the recent progress and remaining challenges of degradable MSNs.

Current bioinformatics tools or databases are very heterogeneous in terms of data formats, database schema, and terminologies. Additionally, most biomedical databases and analysis tools are scattered across different web sites making interoperability across such different services more difficult. It is desired that these diverse databases and analysis tools be normalized, integrated and encompassed with a semantic interface such that users of biological data and tools could communicate with the system in natural language and a workflow could be automatically generated and distributed into appropriate tools. In this paper, the BioSemantic System is presented to bridge complex biological/biomedical research problems and computational solutions via semantic computing. Due to the diversity of problems in various research fields, the semantic capability description language (SCDL) plays an important role as a common language and generic form for problem formalization. Several queries as well as their corresponding SCDL descriptions are provided as examples. For complex applications, multiple SCDL queries may be connected via control structures. For these cases, we present an algorithm to map a user request to one or more existing services if they exist.

The hollow core photonic crystal waveguide biosensor is designed and described. The biosensor was tested in experiments for artificial sweetener identification in drinks. The photonic crystal waveguide biosensor has a high sensitivity to the optical properties of liquids filling up the hollow core. The compactness, good integration ability to different optical systems and compatibility for use in industrial settings make such biosensor very promising for various biomedical applications.

Microwave-induced thermoacoustic imaging (TAI) is a noninvasive modality based on the differences in microwave absorption of various biological tissues. TAI has been extensively researched in recent years, and several studies have revealed that TAI possesses advantages such as high resolution, high contrast, high imaging depth and fast imaging speed. In this paper, we reviewed the development of the TAI technique, its excitation source, data acquisition system and biomedical applications. It is believed that TAI has great potential applications in biomedical research and clinical study.

In spite of attractive bioactivity of bioactive ceramics i.e. hydroxyapatite and bioactive glasses, their poor mechanical properties have restricted their clinical applications. To overcome these limitations, an alternative approach suggested is preparation a composite including these bioactive ceramics with others. It is expected that a ceramic reinforcement with reduced grain size below 100 nm promotes theirs. The aim of this work was fabrication and characterization of hydroxyapatite-forsterite-bioglass composite nanopowder. Novel hydroxyapatite-forsterite-bioglass composite nanopowder was synthesized by incorporation of the forsterite and bioactive glass in hydroxyapatite matrix via a sol-gel process. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fourier transform infrared (FTIR) spectroscopy techniques were utilized in order to evaluate the phase composition, agglomerates size distribution, morphology and particle size and functional groups of synthesized. The effects of sintering temperature and time were also investigated. Results showed that the appropriate temperature for calcination was 600°C and the particle size of composite nanopowder was about 60-70nm. The decomposition of hydroxyapatite was increased with the increase of the sintering temperature and sintering time. Obtained results indicate that prepared composite nanopowder could be a good candidate for medical applications.

Basically, this study was carried out in the context of the development of ferrogel-based biocompatible soft tissue implants, in particular, for the needs of regenerative medicine and replacement therapy. The magneto-deformation effect (MDE) of ferrogels (FGs) and the possibility of its visualization with the use of medical ultrasound were in the focus of this work. The aim of this investigation was addressed to search a possible relationship between the extent of MDE and the intensity of the reflected echo signal at the gel/water interface and in the gel interior. Cylindrical FGs $\sim 12$mm in diameter and $\sim 7$mm in height based on polyacrylamide (PAAm) with interpenetrating physical network of natural polysaccharide (Guar) filled with 200–300nm Fe₃O₄ magnetic microparticles (MPs) with weight fraction of 12% or 23% were investigated. MDE was studied using an ultrasonic medical device Sonoline Adara (Siemens, Germany), and estimated by the relative compression of FGs after application the constant gradient magnetic field (MF) up to 500 Oe by an electromagnet. Viscoelastic and acoustic properties of FGs in the absence of the application of an MF were determined as well. It was found that an increase of the weight fraction of MPs in FGs resulted in the significant increase of the ferrogel’s density, the elastic storage modulus, the loss modulus, the acoustic impedance, the reflection coefficient and some decrease of the ultrasonic velocity in FGs. At a given MPs concentration, the MDE in FGs was increased according to a quadratic law with the gradual increase of MF strength. The growth of MDE in FGs accompanies by an increase in the intensity of the reflected echo signal both from the gel/water interface and from the interior of the FGs. The obtained results are discussed from the viewpoint of the effects of MPs on the interaction of an ultrasonic wave with the structure of FGs in the course of MF application.