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This chapter describes the development of paper-based microchip electrophoresis (pME) devices for the separation of clinically relevant compounds. pME were fabricated by laser cut and thermal lamination process using polyester pouches. In addition, hand-drawn pencil electrodes were integrated to the device to perform capacitively coupled contactless conductivity detection (C 4 D). Finished device costs less than US$ 0.10 and did not require either sophisticated instrumentation or clean room facilities. Furthermore, pME is lightweight, easy to handle, flexible, and robust. pME-C 4 D device revealed an excellent capacity to separate BSA and creatinine in less than 150 s with baseline resolution. The device proposed in this chapter has proven to be a good alternative as a platform for the diagnosis of diseases from renal disorders such as diabetes mellitus and heart disease.

This current review article focuses on recent contributions to on-site forensic investigations. Portable and potentially portable methods are presented and critically discussed about (bio)chemical trace analysis and studies performed outside the controlled laboratory environment to rapidly help in crime scene inquiries or forensic intelligence purposes. A wide range of approaches including electrochemical sensors, microchip electrophoresis, ambient ionization on portable mass spectrometers, handheld Raman and NIR instruments as well as and point-of-need devices, like paper-based platforms, for in-field analysis of latent evidences, controlled substances, drug screening, hazards, and others to assist in law enforcements and solving crime more efficiently are highlighted. The covered examples have successfully demonstrated the huge potential of portable devices for on-site applications. Future investigations should consider analytical validation to compete equality and even replace current gold standard methods., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Simple methods have been developed for fabricating microfluidic paper-based analytical devices (μPADs) but few of these devices can be used with organic solvents and/or aqueous solutions containing surfactants. This study describes a simple fabrication strategy for μPADs that uses readily available scholar glue to create the hydrophobic flow barriers that are resistant to surfactants and organic solvents. Microfluidic structures were defined by magnetic masks designed with either neodymium magnets or magnetic sheets to define the patter, and structures were created by spraying an aqueous solution of glue on the paper surface. The glue-coated paper was then exposed to UV/Vis light for cross-linking to maximize chemical resistance. Examples of microzone arrays and microfluidic devices are demonstrated. μPADs fabricated with scholar glue retained their barriers when used with surfactants, organic solvents, and strong/weak acids and bases unlike common wax-printed barriers. Paper microzones and microfluidic devices were successfully used for colorimetric assays of clinically relevant analytes commonly detected in urinalysis to demonstrate the low background of the barrier material and generally applicability to sensing. The proposed fabrication method is attractive for both its ability to be used with diverse chemistries and the low cost and simplicity of the materials and process., (Copyright © 2017 Elsevier B.V. All rights reserved.)