Novel multi-analyte method for detection of thirty photoinitiators in breakfast cereal and packaged juice.

Multilayer print designs are commonly used in commercial food packaging to attract consumers. UV-curable ink is generally used in this type of printing due to its ease of application, space saving, and rapid drying; however, there have been a number of health alerts related to the contamination of food by photoinitiators in UV-curable ink. In this study, we established a multi-analyte method by which to detect 30 photoinitiators simultaneously. We then applied this method to the analysis of five breakfast cereals and ten types of packaged juice to detect the presence of photoinitiator contamination. Sample treatment was performed using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the extraction of photoinitiators. Chromatographic separation of two isomers, methylbenzophenone (MBP) and isopropylthioxanthone (ITX), was achieved using a pentafluorophenyl propyl (PFP) column (1.7 µm, 100 × 2.1 mm i.d.) and MeOH: 5 mM formic acid-ammonium formate (pH 4.0) in gradient elution. The average recovery of photoinitiators from cereal was between 62.0 and 120.3%, with a coefficient of variation between 0.4 and 14.4%. The average recovery of photoinitiators from packaged juices was between 84.4 and 122.9% with a coefficient of variation between 0.5 and 9.5%. The contamination results were as follows: 13.1 ng/g triphenyl phosphate (TPP) was detected in one breakfast cereal, and 2-hydroxy-4-methoxy benzophenone (BP-3), 1-hydroxycyclohexyl phenyl-ketone (Irgacure 184), methyl-2-benzoylbenzoate (MOBB), and 2,4-diethyl-9H-thioxanthen-9-one (DETX) were detected in one of the packaged juices at levels ranging from 2.2 to 152.9 ng/g.

Metal carbonyl-gold nanoparticle conjugates for highly sensitive SERS detection of organophosphorus pesticides.

The binding of organometallic osmium carbonyl clusters onto the surface of gold nanoparticles (10OsCO-Au NPs) greatly enhanced the CO stretching vibration signal at ~2100cm-1, which is relatively free from interference due to the absorbance of biomolecules. By utilizing the acetylcholinesterase (AChE) mediated hydrolysis of acetylthiocholine to thiocholine where the activity of AChE is inhibited by the presence of organophosphate pesticides (OPPs), the subsequent thiocholine-induced aggregation of 10OsCO-Au NPs can be monitored by the change in color of the NPs solution and the variation in intensity of the SERS CO signal. The change in color offers a fast pre-screening method, whereas monitoring via SERS is used for greater accuracy and lower limit of detection (0.1 ppb) for quantitative detection. Its potential as a quick and accurate method of OPPs monitoring in consumer products was demonstrated in the detection of OPPs in real spiked samples such as beer.

Identification of 3-MCPD esters to verify the adulteration of extra virgin olive oil.

The adulteration of olive oil is an important issue around the world. This paper reports an indirect method by which to identify 3-monochloropropane-1,2-diol (3-MCPD) esters in olive oils. Following sample preparation, the samples were spiked with 1,2-bis-palmitoyl-3-chloropropanediol standard for analysis using gas chromatograph-tandem mass spectrometry. The total recovery ranged from 102.8% to 105.5%, the coefficient of variation ranged from 1.1% to 10.1%, and the limit of quantification was 0.125 mg/kg. The content of 3-MCPD esters in samples of refined olive oil (0.97-20.53 mg/kg) exceeded those of extra virgin olive oil (non-detected to 0.24 mg/kg). These results indicate that the oil refining process increased the content of 3-MCPD esters, which means that they could be used as a target compound for the differentiation of extra virgin olive oil from refined olive oil in order to prevent adulteration.

Temporal trend of polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran and dioxin like-polychlorinated biphenyl concentrations in food from Taiwan markets during 2004-2012.

The levels of polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) or polychlorinated biphenyl (PCB) in foodstuffs have decreased over the past decade in many countries. However, the trend for the levels of these compounds in foodstuffs in Taiwan remains unknown. In this study, we compared the distribution of PCDD/F and PCB in nine foodstuff categories acquired from Taiwan markets from 2004 to 2012. The levels expressed as World Health Organization toxic equivalents (WHO-TEQs) in the different foodstuffs tested were as follows: fish, average 0.463 pg WHO98-TEQ/g sample > seafood, 0.163 pg WHO98-TEQ/g > eggs, 0.150 pg WHO98-TEQ/g > oils, 0.126 pg WHO98-TEQ/g > meats, 0.095 pg WHO98-TEQ/g > dairy products, 0.054 pg WHO98-TEQ/g > cereals, 0.017 pg WHO98-TEQ/g > vegetables, 0.013 pg WHO98-TEQ/g > fruits, 0.009 pg WHO98-TEQ/g. Levels were particularly high in crab (average: 0.6 pg WHO98-TEQ/g sample (1.243 pg WHO98-TEQ/g sample) and large marine fish (0.6). In Taiwan, a decreasing trend of PCDD/Fs or dioxin-like PCBs (dl-PCBs) was observed in meat, dairy, eggs, and vegetables, whereas an elevated trend was observed in cereals or the levels were nearly equal in fruits and oils at alternative time shift. Dl-PCBs contributed to 60-65% toxicity equivalence levels in fish and seafood, but only to 13-40% in meat and cereal samples. The decreasing trend was consistent with the results in other countries; however, the trends in cereals, fruits, and oils were in contrast to previous results reported in other countries. Cereals and fruits are important crops in southern Taiwan, and the local pollution generated by industries or incinerators may seriously affect the distribution of PCDD/Fs and dl-PCBs. To ensure food safety, a risk assessment for residents living in different areas should be adopted for all food categories simultaneously in the future.

A comparison of spring-loaded and vacuum-assisted techniques for stereotactic breast biopsy of impalpable microcalcification lesions: experience at Chang Gung Memorial Hospital at Linkou.

BACKGROUND: The aim of this study was to assess the diagnostic performance of stereotactic core needle breast biopsy using spring-loaded or vacuum-assisted techniques for impalpable microcalcification lesions in Taiwanese women. METHODS: We retrospectively reviewed the data of patients who received stereotactic core needle breast biopsy for impalpable mammographic microcalcification lesions from January 1999 to February 2009. The accuracy, false negative rate, ductal carcinoma in situ (DCIS) upgrade rate and rate of concordance with biopsy procedures were determined. We also compared the diagnostic performance between the vacuum-assisted and spring-loaded techniques. RESULTS: A total of 335 breast stereotactic core needle biopsy procedures (218 by spring-loaded and 117 by vacuum-assisted technique) were enrolled for analysis. The overall accuracy, false negative rate, DCIS upgrade rate and concordance rate with stereotactic core needle biopsy were 88.5%, 17.3%, 23.1% and 83.8% respectively. The vacuum-assisted technique yielded better results than the spring-loaded technique in accuracy (100% vs. 84%), and the false negative (7.1% vs. 21%), DCIS upgrade (0% vs. 37.5%), and concordance rates (95% vs. 79.6%). CONCLUSION: Stereotactic core needle biopsy is a feasible technique in diagnosing impalpable microcalcification lesions of the breast in Taiwanese women. The diagnostic performance of the vacuum-assisted technique was better than that of the spring-loaded technique.

[Multimedia instruction: its efficacy in nurse electrocardiography learning].

BACKGROUND: Rapid enhancements in information technology have focused increasing attention on the potentials of multimedia-assisted instruction in nursing education. Multimedia-assisted instruction not only goes beyond constraints on time and space, it further provides learners with a more active and dynamic environments for learning. In this context, learning becomes easier and more convenient. Most importantly, such instruction has been shown to enhance the effectiveness of student learning. PURPOSE: The purpose of this research was to develop multimedia-assisted teaching materials focused on the subject of electrocardiography and to discuss the resulting efficacy of electrocardiography education relative to the overall in-service nursing education curriculum. METHODS: This study employed a pretest-posttest quasi-experimental design method and purposive sampling. Seventy-seven nurses were enrolled as participants from intensive care units of a Taipei hospital. An EKG knowledge questionnaire was employed to collect data once prior to the start of the course and once following course completion. Data were analyzed using the SPSS 15.0 for Windows software package. RESULTS: RESULTS showed the experimental group scored significantly higher on ECG knowledge after the intervention than the control group. The experimental group further showed significant differences in ECG knowledge in terms of pre- and post-intervention measurements. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: In the future, the strategy of multimedia-assisted instruction should be applied extensively in the nursing staff continuing education curriculum in order to increase learner interest and motivation.