Biossensores e Bioeletrônica

Terahertz spectral analysis has been conducted on epitaxially grown semiconductor structures. Epitaxially grown semiconductors are important for microelectronic and optoelectronic devices and also for integrated circuits fabricated using semiconductors. In this paper, we report results of terahertz time-domain spectroscopy of grown SiGe layers on Ge buffer and separately a Ge buffer that was grown on a Si <001> wafer. In particular, evolution of the time-domain spectra as a function of thickness of both samples was investigated by the terahertz pump-probe technique. Representative spectra were analyzed to determine the respective layers’ spectral signatures. It was found that the spectroscopic analysis uniquely identified different layers by characteristic absorbance peaks. In addition, terahertz imaging was conducted in a non-destructive, non-contact mode for detecting lattice stacking fault and dislocations. Sub-surface imaging of grown SiGe layers on Ge buffer and that of the Ge buffer grown on a Si wafer reveals interesting lattice features in both samples. A comparison with TEM images of the samples exhibits that the terahertz image reproduces the dimensions found from TEM images within the experimental error limits. In particular, 3D images of both samples were generated by the terahertz reconstructive technique. The images were analyzed by graphical means to determine the respective layer thicknesses. Thus, this technique offers a versatile tool for both semiconductor research and in-line inspections.

In this paper I am going to present blood cancer detection using Fluid mechanics variables. Blood cancer is increasing in the world in an exponential manner. It is highly observed in India where smokers are too high in India. Even alcohol consumers are very high in INDIA, blood cancer patients are increasing in an exponential manner. I will be using biosensor for detecting the blood cancer directly through vitro protocol in this paper.

The aim of this work is to introduce bacteria into the matrix of natural phosphate to catalyze the phenol oxidation. The results showed that the NP-bacteria-CPE exhibited excellent electro catalytic activity to phenol. The appearance of three peaks of oxidation shows that the degradation of the phenol was total.

The electropolymerisation of DL-alanine was carried out at the surface of carbon paste electrode by cyclic voltammetric (CV) technique. The fabricated electrode was used for the electrocatalysis of adrenaline at neutral pH. The key parameters like influence of scan rate and concentration reveals the adsorption controlled process. The lower limit of detection was calculated to be 28.0 nM in the linear range of 10 to 60 μM by CV technique. Further, the poly (alanine) modified carbon paste electrode can be used for the selective determination of adrenaline in presence of acetaminophen. Overall, the fabricated electrode can be used as a promising analytical sensor in the determination of adrenaline in pharmaceutical and biological samples.

The tunable and nano-sized materials have recently been received much attention due to the unique physical and chemical properties which are different from bulk materials. Moleculary imprinted polymer (MIP) nanoparticles with special functions provide opportunities for transformative approaches for a wide of variety applications such as imaging, adsorbent, therapeutic reagents, drug delivery vehicles, sensors, toxin neutralization and enzyme inhibition. In this review, the principle, fabrication approaches, parameters to affect affinity and selectivity of MIP were summarized. The application of MIPs for removal of pollutants as well as the separation of macrobiomolecules was also introduced. Through the tuning processes, MIPs can satisfy the needs of simple, fast, cost-effective and robust. In addition, MIPs are easily to be integrated with the diagnosis and separation system, which have instinct advantages in separation, drug delivery, therapeutic and diagnosis fields. Contents shown in this review clearly show that MIPs are highly potential materials for facile design for not only separating the molecules from small molecules to biomolecules by precipitation polymerization but can also be used for imaging, cell tissue engineering and antidotes.

The paper presents the results of research on the development of immune biosensor test system for express detection of polyamines in cells of breast cancer. Determination of polyamines was performed by using an analytical device - immune biosensor based on surface plasmon resonance (SPR), where "antigen-antibody" reaction is performed in real time on the surface of transducer, resulting in formation of immune complexes and recording the shift of resonance angle. The method can detect the studied polyamines spermine and spermidine in concentration less than 10 ng in 1 mL, and with increasing concentrations a statistical probability of the analysis' result rise sharply. Moreover, the dependence of sensitivity of biosensor response from the concentration of polyamines is in the range of 10-100 ng /mL.

Immobilization of enzymes on a variety of different matrices has always attracted researchers to improve the functionality, stability and reusability and its application in bioprocess and biosensors. Present study illustrates a new biological material, jackfruit membrane, as a natural support for immobilization of the urease enzyme for optical detection of urea. A simple protocol was optimized for immobilization of urease enzyme on the membrane. Km of immobilized urease (13.8 mM) was less than that of free urease (39.24 mM). SEM and FTIR studies of the urease immobilized membranes were carried out to characterize the changes after immobilization. Immobilized urease has shown good reusability and stability. Further, immobilized urease was applied for detection study and a detection range between 0.5-10 mM urea was estimated from the linear range of the calibration plot.

Background: In the event of a biological warfare attack, prompt real-time detection methods are necessary to identify the presence of a pathogen well before victims begin exhibiting symptoms in order to allow sufficient time for therapeutic intervention. Current techniques for detecting the presence of biological warfare agents in high-risk environments are exclusively structure-based, relying on the identification of key structural components of specific pathogens that are already well-known and studied. These techniques provide no defense against the modern capability to synthesize new and unfamiliar pathogens of an arbitrary structure that could evade these detection mechanisms.

Methods/Results: This investigation tested the prospect of using electrochemical impedance spectroscopy (EIS) to create a real-time function-based biosensor to identify any cytotoxic substance, whether known or unknown, without regard to its structure. The concept was tested by exposing A549 epithelial adenocarcinoma cells to ricin in several concentrations, ranging from 1 ng/mL to 1000 ng/mL, and observing the effect on the measured impedance of the cells. With as few as three unique trials for each concentration, a statistically significant difference was observed between the impedance data for ricin-exposed cells and that of a ricin-free control group. By comparing the change in the impedance of each sample over periods of 60 minutes and 4 hours, statistically significant detection was achieved within timeframes ranging from 65 minutes after adding 1000 ng/mL ricin to 45 hours after adding 1 ng/mL ricin.

Conclusion: EIS provides a highly sensitive, real-time, and non-destructive method to identify the presence of a cytotoxin. EIS demonstrates rapid detection times that become faster as the concentration increases. Further analysis describes how the design of a potential biosensing device could be used to convert an arbitrary airborne concentration to a media concentration sufficiently large as to achieve detection within the window of time necessary for therapeutic intervention.

The development of the automotive industry is inextricably linked with the development of the ensuring operational effectiveness of the industry production sector, namely service maintenance. Today the car service is an important element at ensuring the competitiveness of products and a tool of improving the customer loyalty.

Despite the fact that there is no direct connection between the ensuring car quality in production and the quality of service in exploitation, it is obviously that the first and the second directions definitely influence on the perceived by a consumer quality of products and services and so they form an attitude of consumer community to the brand maker. That is why the measurement of service maintenance quality is equally important for automaker as the monitoring of the quality of production processes.

At the present time, in the course of solving problems on measuring quality of service maintenance, there has been found a spectrum of methods and techniques allowing to conduct quantitative (the service provider is estimated on a grade scale), qualitative (the quality of customer service is estimated by people responses) and comprehensive quantitative and qualitative researches (they include the above-described estimates).

The aim of this paper is the development and implementation of corporate service quality monitoring system with using internal information of automakers enterprises which in the future, in conjunction with results of the research of the perceived quality service maintenance, will provide the most complete quality assessment covering the corporate environment of automaker and consumer environment.

The development of information and computer technologies has had a beneficial impact on improving monitoring technologies of product and service quality. Development and implementation of information analysis algorithms of service quality allows getting a balanced assessment of consumers reflecting the quantitative and qualitative research area of satisfaction. However, the implementation of service quality researches based on data received by corporate information systems from proprietary service network enterprises to analytical quality services of automakers enterprises about the results of the maintenance and the elimination of defects and failures of cars are not widely represented in the literature, apart from a small group of sources. That is why this theme in the presented work is the main.