Биосенсоры и биоэлектроника

In this work, films have been grown under various deposition conditions in order to understand the effect of processing on the film properties and to specify the optimum condition, different indium oxide (In2O3) contents (0, 1%, 3%, 5% and 7%) using double frequency pulse laser beam (Q-switching) Neodymium-yttrium aluminum garnet (Nd:YAG (wavelength 532 nm)), to deposit Cadmium Oxide: Indium oxide (CdO:In2O3) films on Aluminum Oxide (sapphire α-Al2O3 (006)) and quartz substrates. The structural properties of samples were investigated by using of surface morphology of the deposits materials has been studied by using atomic force microscopy (AFM). The samples are displayed granular structure. It was found that the grain size decreases with increasing of doping concentration ratio, the smallest grain size equal to (79.11 nm) and (82.99 nm) were achieved at ratio of doping (7%) for quartz and sapphire α-Al2O3 substrate, respectively. The sensitivity of undoped and doped CdO samples toward Nitric dioxide (NO2) gas in air ambient has been measured in the home building system. All samples were tested at mixing ratio (3% NO2:air). The optimal operating temperature is found to be 200-225°C for pure CdO and decreases to 175-200°C for samples. The maximum sensitivity is equal to (263.97%) with response time (13.5 s) and recovery time (15.5 s) are achieved at (3%) doping concentration level for sapphire α-Al2O3 substrate.

Electrochemical properties and sensor application of multi-walled carbon nanotubes (MWCNTs), doped with metal oxides [(MO=nickel oxide (NiO), zinc oxide (ZnO) and iron oxide (Fe3O4)] nanoparticles was investigated using FTIR, XRD, UV-vis spectroscopy, Raman spectroscopy, TEM, SEM, EDX, and cyclic voltammetry techniques. Electrochemical oxidation of dopamine on a glassy carbon electrode (GCE) modified with multi-walled carbon nanotubes doped with metal oxides (GCE/MWCNT/NiO, GCE/MWCNT/ZnO, GCE/MWCNT/Fe3O4) was examined by cyclic voltammetry, EIS and square wave voltammetry in 0.1 M phosphate buffer solution PBS at pH 7. The results were compared with those obtained on bare GCE, GCE/MWCNT and MO GCE modified electrodes (GCE/NiO, GCE/ZnO, GCE/Fe3O4). All electrodes were conditioned at potential of 0.2V (vs Ag/AgCl, sat’d KCl) in DA solution for EIS experiment. It was found that the multi- walled carbon nanotubes improve remarkably the reactivity of NiO, ZnO and Fe3O4 for dopamine oxidation. The GCE/MWCNT/NiO, GCE/MWCNT/ZnO, GCE/MWCNT/Fe3O4 electrodes exhibited good linear properties in the concentration range from 4 × 10-5 μM to 6.25 μM for the quantitative analysis of dopamine (DA) with a limit of detection of 7.99 × 10-12 M, 3.742 × 10-7 M and 1.386 × 10-6 M respectively. The limit of detection of GCE/MWCNT/NiO was better than the other two nanocomposites modified electrodes. The interference study also revealed no AA interference signal at AA concentration 1000 times that of DA. The DPV techniques give well distinct peaks for the DA and AA and a wider separation potential. The prepared electrode exhibited satisfactory stability and long shelf life when stored at ambient conditions. It has been demonstrated that the GCE/MWCNT/NiO modified electrode can be successfully used for the assay of dopamine in some real samples.

We describe our real-time biosensing approach to detecting and managing head impacts in football at the University of Mississippi as well as the Heads in the Game, our high school outreach program. Our work is in response to the fact that sports are the second leading cause of traumatic brain injury for people aged between 15 and 24 years [1,2]. Additionally, the Center for Disease Control estimates indicate that 5,000 concussions occur at the high-school level for every concussion in the NFL, and that 3.8 million sports brain injuries occur annually. Mild Traumatic Brain Injures (mTBI) are often not reported in high school football due to injury underestimation, motivation to remain in play, and lack of awareness. Resources and education for improved athlete concussion management reduces the player's susceptibility to cumulative or catastrophic brain injuries [3]. Our system uses X2 Biosystem’s xPatch 6DOF mounted directly behind the player’s ear and features a secure wireless telemetry system for reporting head impacts in real time to an analysis system that is capable of reporting the major characteristics of the impact in near real time. Collected data will also contribute to understanding the potential long-term effects brain injuries such as second impact syndrome (SIS) [4]. Pilot studies with the University of Mississippi football team show significant reduction of head impacts through improved form and education. By reducing the overall head impact, improving impact distribution, and reducing dangerous impacts, mechanisms for improving remove-from-play (RFP) and returnto- play (RTP) decisions, assessing impact severity, coaching and training, and understanding the pathology of mTBI and long-term brain injuries causing persistent cognitive impairment. We discuss research partnerships as well as the Heads in the Game program, a high school concussion research program with University of Mississippi Athletics

The prevalence of gout in the United States has risen over the last twenty years and gout now affects 8.3 million Americans. Currently, gout is diagnosed either by extracting a fluid sample from the joint to look for formation of uric acid crystals or by drawing blood to measure the level of uric acid. Both of these methods are invasive, cumbersome, and time-consuming. The purpose of this study is to prevent gout attack with a novel approach called "noninvasive infrared uric acid monitoring." This approach utilizes a cost-effective and portable near-infrared (NIR) spectroscopybased device that can offer quick, noninvasive, and preventative way to monitor the patient's uric acid level. By using uric acid infrared spectroscopy characteristics, infrared wavelengths between 1400 to 1700nm are emitted on uric acid samples and detector senses non-absorbed Infrared light. The detected NIR signal gets amplified and filtered to maintain a high signal to noise ratio (SNR) over the wavelengths of interest. A linear regression algorithm is used to distinguish and predict the uric acid concentration among other biomarkers in the sample. Finally, a digital signal processing was used to process the data. Based on the Beer-Lambert's law, a linear relationship between the light absorbance and uric acid concentration is expected. Minimum detectable change in uric acid level was analyzed and a mathematical model was compared to the measured data. Another potential benefit of this approach is its versatility. By modifying infrared wavelength and the calibration system in the DSP chip, other biomarkers can be measured.

Electroencephalogram (EEG) is a test used to detect abnormalities related to electrical activity of the brain. In this work different finite impulse response filter (FIR) windows methods were used to extract EEG signal to its basic components (Delta wave, Theta wave, Alpha wave and Beta wave). The comparison between these windowing methods were done by computing the Fourier transform, power spectrum, SNR, the main-lobe, and the side-lobe. The results show the best main-lobe is for rectangular window, the best side-lobe is for Kaiser β (12) and the best SNR is for Hanning. Also the best window according to main-lobe, side-lobe and SNR is Kaiser β (12).

Creatine modification for commercialization has included many variations to increase its stability. The current report assesses the stability of a sodium bicarbonate buffered creatine sold under the brand name Kre-Alkalyn under various conditions. Kre-Alkalyn is shown to have a good 6 year stability and shelf life under accelerated testing. It maintains a high pH over time compared to normal creatine and can be augmented with additional stabilizing buffers. This stability and buffering profile may serve useful in providing continued creatine availability.

Plant circadian system works autonomously and responds to various environmental information in cellular level. Conventional studies on controlling of the plant circadian system, however, have not thoroughly considered in cellular level yet. In this study, we investigated spatiotemporal dynamics of cellular circadian rhythms of clock gene CCA1 in leaves that were controlled by the projector lightings in a transgenic lettuce strain AtCCA1::LUC using a bioluminescence imaging. We have succeeded to control the cellular circadian rhythms in the both case of LCD and laser projectors with 24 or 26 h periods of light-dark cycles. Although light intensity of the laser projector was very small to a required light intensity for growth of lettuces, the circadian rhythm was entrained with high sensitivity for illumination. Our results motivate experimental and theoretical studies of circadian control and development for the highly functional lighting technology in plant productions.

A simple and easy method is demonstrated for the fabrication of liquid molds which was used for the fabricaion of bio-polydimethylsiloxan (Bio-PDMS) mirofluidic devices based on a novel drop-on-demand (DOD) printing technology. The liquid molds were DOD printed well on the hydrophilic glass substrate which was treated with a TiO2 nanoparticles (TiO2NPs) solution at the overlap of 30%. Then the PDMS concave molds were fabricated well by being replicated from the liquid molds and were bonded with another PDMS substrate to form a Bio-PMDS mirofluidic device. The micro-channel which the width and the height were about 100 μm and 8 μm was fabricated and the surface roughness of the micro-channel with the 100×320 μm2 area was about 179 nm measured by a white light interferometer. The experimental results showed that the width of micro-channel in the Bio-PDMS microfluidic device was small and the surface of the micro-channel was smooth.

A new prototype of Electronic Nose instrument, Multisensory Odor Olfactory System MOOSY32, with a processing method based on a multivariate classification analysis was used to assess different postharvest and storage treatments effects to Salustiana oranges. The analysis method is based on the measurement of the volatile compounds produced under different environmental and operational conditions. The Electronic Nose system revealed that orange juice flavor changes even when juices are analyzed right after each treatment and fruits are stored under refrigerated conditions. The instrument was able to detect even small changes in the aromatic pattern of the juices, confirming that the packing line itself is able to cause perceptible changes in the flavor. This can be a new and important finding in the Salustiana orange treatment that can lead to a significant improvement of fruits quality on the markets.

Controlling the behavior of adsorbed and immobilized proteins is essential for protein purification and a wide range of applications, including biosensors, biocatalysis and biomedical devices. In this study, monodisperse polymer particles were synthesized by soap free emulsion polymerization and the surface functional groups were directly introduced as a monomer or chemically modified with epoxy groups to enable protein immobilization through covalent bonding. Three kinds of surface charged particles having cationic, anionic, or both, groups were synthesized and characterized. Bovine serum albumin (BSA) was selected as a model protein to study the effect of pH of a buffer solution containing protein on the adsorption and immobilization amount. Protein adsorption was found to be strongly affected by pH and matching of the global protein and polymer particle charges, respectively. When pH was below the pI of either protein (pH 3.8), negatively charged polymer particles were found to adsorb a high amount of proteins. At maximum surface coverage of BSA on negatively charged polymer particles at pH 3.8 and after subsequent rinsing of the BSA-polymer particle complex with phosphate buffer (pH 7), ~50% of BSA was desorbed. Therefore, 50% of BSA was adsorbed by ionic interaction and the remaining fraction was immobilized covalently at pH 3.8. The remaining immobilized fraction was sufficient to completely shield the anionic charge of the polymer particles. Fluorescence spectroscopy suggests that at maximum immobilized amounts, the conformation of immobilized BSA appears to be the same as in aqueous solution.

We apply mathematical models for the interaction of the internal and biologically active points of meridian structures. Amongst the diseases for which reflex diagnostics are effective are those of the stomach disease. It is shown that use of fuzzy logic decision-making yields good results for the prediction and early diagnosis of stomach diseases, depending on the reaction energy of biologically active points (acupuncture points). It is shown that good results for the prediction and early diagnosis of diseases from the reaction energy of biologically active points (acupuncture points) are obtained by using fuzzy logic decision-making. Analysis of resistances lower and higher than the nominal values allowed us to specify the prognostic and diagnostic models.