High-performance biosensing systems based on various nanomaterials as signal transducers

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An Analysis of the Incorporated Values in English for Palestine 12

This descriptive analytic study aims at identifying the existed values in the content of English for Palestine- grade twelve textbook, as it was applied in the scholastic year 2006-2007 for grade twelve students in West Bank and Gaza Strip. The purpose for the study is to investigate the existence of the list of values in the content of the targeted textbook as they are very important for guiding and engaging learners into life to be active members in their societies. Based upon previous studies, literature review and international models, the researcher created a model for classifying values which suits Palestinian students and it also matches international models. She came out with eight main domains. They are theoretical, economic, aesthetic, social, political, religious, cultural and patriotic. In the content analysis, the researcher depended upon the eight domains of values. These involved surveying the textbook so as to analyze the activities that match the eight domains of the study. A panel of expert validated the eight domains of values. They examined the reliability by reanalyzing the textbook after 30 days and analyzing it by a twelve grade teachers. The findings showed variation in the frequencies of the eight domains and in each domain as well. Cultural values domain reached the highest score of 20.8%, 48 frequencies. The next score was the theoretical values that reached a score of 20%,46 frequencies. economic values domain was the third position with 17.8%,41 frequencies. The fourth was represented in the social values that reached 13.9%,32 frequencies. Aesthetic values was the fifth position with 10%, 23 frequencies. The sixth was patriotic values that reached 8.6%, 20 frequencies. The lowest score was religious and political with only 4.3%, 10 frequencies. The researcher recognized the distribution of the domains and their items among the content of the textbook. She indicated that there should be a balance in distributing the domains and the items among the activities and units. Balance does not mean equality, but distributing them according to criteria of a balanced scale that matches the importance and need of every value. The findings showed variety of topics distributed within the content of the units of the textbook. Variety indicated positive points in the content of the textbook. Recommendations were drawn to make balance in distributing the eight domains of values in the content of the textbook. Therefore, the researcher also recommended reviewing the existed material associated with the different models for classifying values. Workshops should be held in order to discuss strengths and weakness of the textbook to support strong points and develop weakness

Investigation on the applicability of a long-range reverse-transcription quantitative polymerase chain reaction assay for the rapid detection of active viruses

Abstract Background Although conventional polymerase chain reaction (PCR) methods are widely used in diagnosis, the titer of the pathogenic virus is difficult to determine based on the PCR. In our prior report, a long-range reverse-transcription quantitative PCR (LR-RT-qPCR) assay was developed to assess the titer of UV-irradiated influenza A virus (IAV) rapidly. In this research, we focused on whether the LR-RT-qPCR assay could evaluate the titer of IAV inactivated by other methods. Methods IAV was inactivated by: heating at 100 °C for periods ranging from 1 to 15 min, treating with 0.12% sodium hypochlorite for periods ranging from 3 to 30 min, or treating with 70% ethanol for periods ranging from 10 to 30 min. Fifty percent tissue culture infectious dose (TCID50) assay was performed to confirm the efficacy of the inactivation methods, followed by LR-RT-qPCR to investigate the correlation between infectivity and copy number. Results One minute heating, 3 min sodium hypochlorite treatment, or 10 min ethanol treatment was sufficient to deactivate IAV. Changes before and after the inactivations in the copy numbers on LR-RT-qPCR were significantly different among the inactivation methods. Heat-inactivation drastically decreased the copy number to below the cutoff value around 5 copies/μL after 5 min treatment. The inactivation time of heating estimated using LR-RT-qPCR was marginally higher than that determined using TCID50. However, the treatments with sodium hypochlorite or ethanol moderately and minimally affected the copy numbers obtained using LR-RT-qPCR (~ 1 digit or no copy number decrease), respectively. Conclusions In addition to good applicability in UV-irradiation previously reported, the LR-RT-qPCR method is suitable for evaluating the effect of heat-inactivation on IAV infectivity. However, minor modifications may be made and investigated in the future to reduce the time intervals with TCID50. Although this method is not applicable for the ethanol inactivation, rapid evaluation of the effects of chlorination on IAV can be determined by comparing copy numbers before and after treatment using the LR-RT-qPCR method

Carbon Nanotubes as Fluorescent Labels for Surface Plasmon Resonance-Assisted Fluoroimmunoassay

The photoluminescence properties of carbon nanotubes (CNTs), including the large Stokes shift and the absence of fluorescent photobleaching, can be used as a fluorescent label in biological measurements. In this study, the performance of CNTs as a fluorescent label for surface plasmon resonance (SPR)-assisted fluoroimmunoassay is evaluated. The fluorescence of (8, 3) CNTs with an excitation wavelength of 670 nm and an emission wavelength of 970 nm is observed using a sensor chip equipped with a prism-integrated microfluidic channel to excite the SPR. The minimum detectable concentration of a CNT dispersed in water using a visible camera is 0.25 μg/mL, which is equivalent to 2 × 1010 tubes/mL. The target analyte detection using the CNT fluorescent labels is theoretically investigated by evaluating the detectable number of CNTs in a detection volume. Assuming detection of virus particles which are bound with 100 CNT labels, the minimum number of detectable virus particles is calculated to be 900. The result indicates that CNTs are effective fluorescent labels for SPR-assisted fluoroimmunoassay

Sensitive Detection of C-Reactive Protein by One-Step Method Based on a Waveguide-Mode Sensor

One-step biosensing methods enable the quick and simplified detection of biological substances. In this study, we developed a sensitive one-step method on the basis of a waveguide-mode sensor, which is an optical sensor utilizing waveguide-mode resonance and evanescent light. Streptavidin-conjugated and gold-nanoparticle-conjugated antibodies were reacted with a target substance and applied onto a biotinylated sensing plate. The target substance was detected by observing changes in sensor signals caused by binding the immunocomplex to the sensing surface. Performance of the developed one-step method was examined using a C-reactive protein (CRP) as a target substance. A sensor signal corresponding to the concentration of CRP was obtained. The minimal detectable CRP concentration of the developed method was 10 pM. The developed method greatly simplifies quantitative protein detection without reducing sensitivity