This paper presents a handheld device that is capable of simplifying multistep assays to perform sensitive detection of foodborne pathogens. The device is capable of multiplexed detection of Escherichia coli (E. coli) O157:H7, Salmonella Typhimurium (S. Typhimurium), Staphylococcus aureus, and Bacillus cereus. The limit of detection for each bacterium was characterized, and then, the detection of bacteria from contaminated fresh lettuces was demonstrated for two representative foodborne pathogens. We employed a sample pretreatment protocol to recover and concentrate target bacteria from contaminated lettuces, which can detect 1.87 × 10 CFU of E. coli O157:H7 and 1.47 × 10 CFU of S. Typhimurium/1 g of lettuce without an enrichment process. Lastly, we demonstrated that the limit of detection can be reduced to 1 CFU of E. coli O157:H7 and 1 CFU of S. Typhimurium/1 g of lettuce by including a 6 h enrichment of contaminated lettuces in growth media before pretreatment.

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A procedure for direct conversion of long chain triglycerides to their corresponding ether derivatives has been accomplished using a combination of lithium aluminum hydride and boron trifluoride etherate. Reaction products obtained from reduction of tristearin or trimyristin were isolated by thin layer and column chromatography and identified using infrared spectroscopy. Glyceryl triethers, glyceryl monoethers, and aliphatic alcohols were the major reaction products, making up 2–3%, 9–19%, and 43–75%, respectively, of the theoretical molar yields. Yields of both ether derivatives were increased when a lithium aluminum hydride solution was added to a mixture of triglyceride and boron trifluoride etherate rather than adding a mixture of triglyceride and boron trifluoride etherate to lithium aluminum hydride. Increasing the quantities of lithium aluminum hydride increased glyceryl triether yield, but decreased glyceryl monoether yield.