Forensic collection of trace chemicals from diverse surfaces with strippable coatings.

Surface sampling for chemical analysis plays a vital role in environmental monitoring, industrial hygiene, homeland security and forensics. The standard surface sampling tool, a simple cotton gauze pad, is failing to meet the needs of the community as analytical techniques become more sensitive and the variety of analytes increases. In previous work, we demonstrated the efficacy of non-destructive, conformal, spray-on strippable coatings for chemical collection from simple glass surfaces. Here we expand that work by presenting chemical collection at a low spiking level (0.1 g m(-2)) from a diverse array of common surfaces - painted metal, engineering plastics, painted wallboard and concrete - using strippable coatings. The collection efficiency of the strippable coatings is compared to and far exceeds gauze pads. Collection from concrete, a particular challenge for wipes like gauze, averaged 73% over eight chemically diverse compounds for the strippable coatings whereas gauze averaged 10%.

Strippable coatings for forensic collection of trace chemicals from surfaces.

Surface sampling for chemical analysis plays a vital role in applications like environmental monitoring, industrial hygiene, homeland security, and forensics. The standard surface sampling tool is a simple cotton gauze pad, but as techniques become more sensitive and the variety of analytes increases, gauze is failing to meet the needs of the community. Here, the collection of eight small molecules from glass surfaces with three different commercial spray-on, strippable coatings was demonstrated and their collection efficiency, as measured by gas chromatography/mass spectrometry, was compared to that of a standard cotton gauze. The three coating systems recovered 87-95% of the each compound, on average, from a nominal initial surface coverage of 0.1 g/m(2) per analyte. These recoveries were 3-fold better than the cotton gauze which had an average collection efficiency of 31%.

Microstructured reactors as tools for the intensification of pharmaceutical reactions and processes.

Process intensification is a design philosophy that aims to reduce the cost and energy input into chemical processes, while simultaneously increasing yield and purity. Microstructured reactors have an important role to play in the implementation of this philosophy, as the transformation from batch to continuous processing and the heat and mass transfer characteristics of these reactors allows precise control of reaction time, temperature and mixing, leading to improvements in selectivity and conversion for organic reactions. This review highlights some of the remaining challenges to the widespread adoption of these reactors, and the progress being made toward overcoming these issues.

Biosensing with polydiacetylene materials: structures, optical properties and applications.

Polydiacetylene (PDA) materials are used as a platform for detection of biological analytes such as microorganisms, viruses and proteins. The environmentally responsive chromic and emissive properties of the polymer, combined with self-assembled material formats, make these materials particularly attractive for biosensing applications. A variety of approaches have been used in developing these materials and demonstrating their potential for biological detection. In this feature article we describe different PDA material formats, discuss the optical properties that are the basis for signal generation, and review the use of PDA for biosensing.

Antibody-functionalized polydiacetylene coatings on nanoporous membranes for microorganism detection.

The preparation and characterization of coatings made from polydiacetylene colloids on nano- and microporous membranes and their potential for the detection of microorganisms are presented.