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Candies, chewing gums, dried fruits, jellies, chocolate, and shredded squid pieces imported from 17 countries were surveyed for their aluminum content. The samples were bought from candy shops, supermarkets, and convenience stores, and through online shopping. Sample selection focused on imported candies and snacks. A total of 67 samples, including five chewing gums, seven dried fruits, 13 chocolates, two jellies, two dried squid pieces, and 38 candies, were analyzed. The content of aluminum was analyzed by inductively coupled plasma optical emission spectrometry (ICP OES). The limit of quantitation for aluminum was 1.53 mg/kg. The content of aluminum ranged from not detected (ND) to 828.9 mg/kg. The mean concentrations of aluminum in chewing gums, dried fruits, chocolate, jellies, dried squid pieces, and candies were 36.62 mg/kg, 300.06 mg/kg, 9.1 mg/kg, 2.3 mg/kg, 7.8 mg/kg, and 24.26 mg/kg, respectively. Some samples had relatively high aluminum content. The highest aluminum content of 828.9 mg/kg was found in dried papaya threads imported from Thailand. Candies imported from Thailand and Vietnam had aluminum contents of 265.7 mg/kg and 333.1 mg/kg, respectively. Exposure risk assessment based on data from the Taiwan National Food Consumption Database was employed to calculate the percent provisional tolerable weekly intake (%PTWI). The percent provisional tolerable weekly intake of aluminum for adults (19–50 years) and children (3–6 years) based on the consumption rate of the total population showed that candies and snacks did not contribute greatly to aluminum exposure. By contrast, in the exposure assessment based on the consumers-only consumption rate, the estimated values of weekly exposure to aluminum from dried papaya threads in adults (19–50 years) and children (3–6 years) were 4.18 mg/kg body weight (bw)/wk and 7.93 mg/kg bw/wk, respectively, for 50 th percentile consumers, and 6.26 mg/kg bw/wk and 12.88 mg/kg bw/wk, respectively, for 95 th percentile consumers.

In this study, a commercially available fluorescent dye, Lissamine rhodamine B sulfonyl hydrazine (LRSH), was designed to specifically stain the glycoproteins in polyacrylamide gels. Through the periodate/Schiff base mechanism, the fluorescent dye readily attaches to glycoproteins and the fluorescence can be simultaneously observed under either 305 nm or 532 nm excitation therefore, the dye-stained glycoproteins can be detected under a regular UV transilluminator or a more elegant laser-based gel scanner. The specificity and detection limit were examined using a standard protein mixture in polyacrylamide gels in this study. The application of this glycoprotein stain dye was further demonstrated using pregnancy urine samples. The fluorescent spots were further digested in gel and their identities confirmed through LC-MS/MS analysis and database searching. In addition, the N-glycosylation sites of LRSH-labeled uromodulin were readily mapped via in-gel PNGaseF deglycosylation and LC-MS/MS analysis, which indicated that this fluorescent dye labeling does not interfere with enzymatic deglycosylation. Hence, the application of this simple and specific dual-wavelength excitable dye staining in current glycoproteome research is promising.

Several novel mesogenic spiro‐orthoester monomers such as 1,6,10‐trioxaspiro[4,5]decanes 4, containing biphenyl mesogens at the C‐8 positions of the five‐ and six‐membered spirocyclic ring, through the alkylene spacers of different lengths were prepared by condensation reaction of the corresponding biphenyl mesogenic 1,3‐propanediol 3 with 2,2‐diethoxytetrahydrofuran, with 50–75% yields. Through cationic double ring‐opening polymerization, carried out with boron trifluoride etherate as an initiator (5 mol % vs. monomer) in bulk at 150°C, spiro‐orthoester monomers 4 afforded a novel class of side‐chain thermotropic LC polymers with a poly(ether ester) as the main chain 8. The liquid‐crystalline properties of the spiro‐orthoester monomers and the resulting polymers were examined by differential scanning calorimetry and optical polarized microscopy. Biphase separation was observed in the side‐chain liquid‐crystalline poly(ether ester)s upon annealing in the broad isotropic region. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2439–2455, 1998