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Miniaturized separation techniques have emerged as environmentally friendly alternatives to available separation methods. Nano-liquid chromatography (nano-LC), microchip devices and nano-capillary electrophoresis are miniaturized methods that minimize reagent consumption and waste generation. Furthermore, the low levels of analytes, especially in biological samples, promote the search for more highly sensitive techniques; coupled to mass spectrometry, nano-LC has great potential to become an indispensable tool for routine analysis of biomolecules. This short review presents the fundamental aspects of nano-LC analytical instrumentation, discussing practical considerations and the primary differences between miniaturized and conventional instrumentation. Some theoretical aspects are discussed to better explain both the potential and the principal limitations of nano-LC. Recent pharmaceutical and biomedical applications of this separation technique are also presented to indicate the satisfactory performance for complex matrices, especially for proteomic analysis, that is obtained with nano-LC.

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Green Analytical Chemistry (GAC) is a research field that seeks for more sustainable analytical approaches to minimize the toxicity and amounts of wastes without hindering the analytical performance. This is a trend in Analytical Chemistry worldwide and because of the diversity of innovations on this subject, Brazil stands out as the third in the list of the main contributors to GAC, with ca. 11.2% of the published articles. Significant innovations and interesting applications in several fields have been presented and Brazil is continuously moving from Chemistry to Green Chemistry also in the Analytical Chemistry field. Selected contributions for sample preparation, spectro-and electroanalysis, separation techniques, chemometrics, and also procedures for point-of-care measurements are critically reviewed.

A pentafluorobenzamide stationary phase was synthesized by an easy method with no intermediate purification steps. Physicochemical characterization (elemental analysis, fourier transform infrared spectroscopy, Si and C nuclear magnetic resonance spectroscopy) confirmed the presence of pentafluorobenzamide functionalization on the surface of the silica particles. The pentafluorobenzamide stationary phase proved to be quite versatile as it can be used in two different modes in liquid chromatography: reversed phase and hydrophilic interaction liquid chromatography. Chromatographic characterizations in both modes confirmed the multiple interactions established by the new stationary phase, such as hydrogen bonding and π-π and ion-exchange interactions. The pentafluorobenzamide stationary phase was successfully employed for the separation of nucleosides and antihypertensive drugs under hydrophilic interaction liquid chromatography conditions, as well as pesticides and benzodiazepine using reversed phase conditions. The stationary phase showed significant potential when compared with commercial columns.