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In this study, a highly sensitive and quantitative analysis method using surface-enhanced Raman scattering (SERS)-labeled immunoassay is adopted for bisphenol A bisphenol A (BPA) detection in water samples.

Primarily, an excellent SERS immuno-nanoprobe is prepared, which relays on Au/Ag core-shell nanoparticles tagged 4-mercaptobenzoic acid (4MBA) and labeled with specific antibody against BPA. Second, the coating antigen of 4,4-Bis(4-hydroxyphenol) valeric acid (BVA) coupling poly-L-lysine (PLL) conjugate (BVA-PLL) is fastened on the substrate. Based on competitive immunoassay, the antibody labeled on SERS immuno-nanoprobe will bind with the free BPA and BVA-PLL competitively.

A calibration curve was obtained by plotting the intensity of SERS signal of 4MBA at 1007 cm⁻¹ versus the concentration of BPA. The results indicated that the limit of detection (LOD) for BPA is 1 ng/mL and present a great capacity for higher sensitivity. Furthermore, the method was able to quantitatively detect BPA in water samples, which was validated by high performance liquid chromatography (HPLC).

The method was developed based on competitive immunoassay, and the conjugate (BVA-PLL) was chosen as the coating antigen. Au/Ag core-shell nanoparticles played as the SERS active substrate and were labeled with Raman reporter. The value of this paper is supplying a wide potential for analysis of target analytes in the environmental monitoring and food safety.

Biomonitoring uses biological responses to assess environmental changes, which are frequently due to anthropogenic pollution. Biomonitoring can be carried out at different levels of complexity: population, species or suborganismic responses may be used as indicators for exposure to pollutants. In the case of tests with whole organisms, their quality is often impaired by the heterogeneity of living organisms, slow responses and the fact that little information can be provided on the pollutants. Although suborganismic tests can provide more specific and fast responses, structure and concentration of pollutants are only revealed by chemical analysis. A novel approach to biomonitoring is introduced, which applies tight coupling of bioassays and chemical analysis and is defined as bioresponse‐linked instrumental analysis. It combines biomolecular recognition, initiating a biological effect and chemical analysis.

After implementing an internal quality control (IQC) programme, the purpose of this paper is to maintain the requisite analytical performance for clinical laboratory staff, thereby safeguarding patient test results for their intended medical purpose.

The authors address how quality can be maintained and if lost, how it can be regained. The methodology is based on the experience working in clinical laboratory diagnostics and is in accord with both international accreditation requirements and laboratory best practice guidelines.

Monitoring test performance usually involves both prospective and retrospective IQC data analysis. The authors present a number of different approaches together with software tools currently available and emerging, that permit performance monitoring at the level of the individual analyser, across analysers and laboratories (networks). The authors make recommendations on the appropriate response to IQC rule warnings, failures and metrics that indicate analytical control loss, that either precludes further analysis, or signifies deteriorating performance and eventual unsuitability. The authors provide guidance on systematic troubleshooting, to identify undesirable performance and consider risk assessment preventive measures and continuous quality improvement initiatives; e.g., material acceptance procedures, as tools to help regain and maintain analytical control and minimise potential for patient harm.

The authors provide a template for use by laboratory scientific personnel that ensures the optimal monitoring of analytical test performance and response when it changes undesirably.

The proposed template has been designed to meet the International Organisation for Standardisation for medical laboratories ISO15189:2012 requirements and therefore includes the use of External Quality Assessment and patient results data, as an adjunct to IQC data.

The smoking rate of male high school students continues to increase. Therefore, the purpose of this paper is to examine the effectiveness of a smoking cessation program on self-esteem, attitude, perception and practice regarding smoking behavioral control among male high school students in Ubon Ratchathani Province, Thailand.

The effectiveness of the smoking cessation program was tested by a quasi-experimental pre-posttest and follow-up with a 24-week design. Multistage sampling was used to recruit 70 male high school students, including 35 male students in the intervention group and 35 male students in the control group. The intervention group received a 12-week smoking cessation program based on information-motivation-behavioral skills and stages of change models and follow-up at 12 weeks, whereas the control group did not. A self-administered questionnaire was used to assess the improvement of subjects’ self-esteem, attitude toward smoking, perceived control over smoking, number of cigarettes per day and urine cotinine test. The descriptive statistics, generalized estimating equation and proportion test were used for data analysis.

After the program, there were statistically significant differences in mean scores between the group and control groups; the difference of self-esteem was 4.15 (95% CI: 1.95, 6.36), attitude toward smoking was 3.30 (95% CI: 1.89, 5.52) and perceived control over smoking was 6.99 (95% CI: 4.04, 9.94). Thus, all differences in the intervention group were significantly higher than in the control group. The proportion of non-smokers, measured by the urine cotinine test at follow-up, was 25 percent (95% CI: 0.03, 0.48) significantly higher (p-value = 0.015), in the intervention group. Therefore, the smoking cessation program in this study was effective at changing the behavior of male high school student smokers.

This smoking cessation program increased self-esteem, attitude toward smoking, perceived control over smoking and decreased smoking per day among male high school students. Therefore, schools and parents should focus on developing these factors to encourage students to quit smoking.

Antibodies are produced by the immune system in response to invasion of the body by ‘foreign’ material. Molecules larger than 1000 molecular weight including proteins, polysaccharides and lipids are immunogenic. Recognition of the foreign substance by receptors on the surface of B lymphocytes in the blood stimulates the cell to multiply and to produce antibodies capable of binding specifically to the compound. Each lymphocyte clone produces only one antibody, but many different lymphocytes (and thus antibodies) may be stimulated by a single immunogen.

This paper aims to investigate the effects on material performance in the epoxy acrylate resin system owing to the existence of the different ring of the cyclic methacrylate. In this paper, cyclic methacrylate as diluents was added into epoxy acrylate (EA) resin by ultraviolet (UV)-cured polymerization to investigate the effects on material performance owing to the existence of the different rings.

EA and 1-adamantyl methacrylate were synthesized by traditional methods according to previous papers, respectively. After adding different cyclic methacrylate as diluents to the EA oligomers, the system was exposed to the UV-light for polymerization.

The hydrophobic properties of the cured materials were increased slightly because of the alkyl groups from the methacrylate. The thermal stabilities and mechanical properties of the resins were enhanced by the cyclic diluents with the hard segments. Meanwhile, the crosslink density of the polymer decreased with the bulky group like adamantly owing to its huge structure.

The cyclic methacrylates were introduced into EA oligomers for decreasing the viscosity and increasing the materials performances, which could be recognized as new diluents applied in UV-cued polymerization.

The results of this study will be conducive to fabricate EA resins possessed with high thermal stabilities and mechanical properties by convenient UV-cured polymerization.

This paper considers the role of biosensors for monitoring the environment. A selection of existing products and competitive techniques such as biochemical assays and laboratory analysis which presently dominate the business are discussed. A number of research activities and themes are considered. Conclusion are drawn on the prospects for environmental biosensors.

Describes the history and development of biosensors and their commercial application.

Provides background information on different forms of biosensors and how they can be brought to market. This review is edited from a very detailed market research report “Medical and Biological Sensor and Sensor Systems: markets, applications and competitors worldwide”.

Finds that the commercial potential for biosensors is very large and is expected to reach US$ 2.3 billion worldwide in 2005.

The full market research report provides a detailed insight into biosensors and how they are made and the various application areas, together with discussion regarding a large number of vendor and research companies.

Phosphatidylserine (PS) extracted from both bovine cortex and soya beans has been previously reported to positively affect cognitive functioning, mood, and the capacity to cope with stress. The present paper aims to investigate whether the daily intake of phospholipid concentrate (PL) rich in phosphatidylserine (PS) and sphingomyelin (SM) has similar beneficial effects on working memory, allostastic load and the acute stress response.

A total of 46 healthy men (average 41.5 years) received either placebo or 13.5 g per day PL over a three‐week period. On the 21st day of PL intake, subjects' working memory performance and their psychological and endocrine responses to the Trier Social Stress Test (TSST) were tested.

Compared to placebo‐exposed individuals, there was a tendency for shorter reaction times in the working memory task, suggesting better performance in PL‐treated subjects. The two treatment groups did not significantly differ in their endocrine stress response. However, PL‐treated subjects with a higher stress load showed a blunted psychological stress response.

Results of the present study show beneficial effects of PL intake on cognitive performance. Under acute stress, benefits of PL may only be visible in chronically stressed subjects.

This paper provides new information for practitioners, academics and food supplement industries interested in possible beneficial effects of a milk phospholipid product on memory and mental stress.