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The article develops a method that involves a three-step reaction pathway, to attach fluorescein-5'-isothiocyanate (FITC) molecules to the surface of cellulose nanocrystals. It is stated that cellulose nanocrystals enable the use of fluorescence techniques, such as spectrofluorometry, fluorescence microscopy, and flow cytometry to study the interaction of cellulose nanocrystals with cells and the biodistribution of cellulose nanocrystals in vivo.

Very little is known about mixed polybrominated/chlorinated dibenzo-p-dioxins and dibenzofurans (PBCDD/F) in industrial thermal processes. In this study, the occurrences and characteristics of PBCDD/F from various incineration and metallurgical processes were investigated. In addition, PBCDD/F analytical protocols based on HRGC/HRMS were developed and optimized. The sum of isomer group concentrations ranged from 1.7-3740 pmol Nm-3 for PBCDF and 0.2-582 pmol Nm-3 for PBCDD. For some metallurgical industries, the amounts of PBDD/F and PBCDD/F emitted were similar to or even higher than the amounts of PCDD/F. The sources of bromine and brominated-precursors in these processes should be evaluated. The PBCDD/F characteristics investigated included isomer group patterns, ratio of bromine and chlorine incorporated in PBCDD/F, and ratio of halogenated furans to dioxins. Lower brominated PBCDD/F were binomially distributed. But in some cases, the concentrations of higher brominated PBCDD/F were much higher than predicted from the binomial distribution. The formation mechanisms of PBDD/F, PBCDD/F, and PCDD/F in these processes were also evaluated. [ABSTRACT FROM AUTHOR]