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In this review, we discuss recent reproductive organ-on-a-chip (OoC) experiments that encompass multiple target areas of investigation, including model fabrication strategies, transport mechanisms, and immunology. We highlight fetal membrane and placental biology, OoC history and background, and the designs of reproductive OoC platforms. Reproductive OoC designs include fetal membrane models such as the Fetal Membrane-on-a-chip (FMOC) and others, placental models such as the placenta on-a-chip, and full reproductive tract models such as EVATAR. Diverse fabrication strategies and the integration of multiple model materials are explored. OoC samples can be analyzed with many analytical techniques, including mass spectrometry, fluorescence microscopy, ELISAs, impedance spectroscopy, and electrochemical techniques. The future of reproductive OoC models is a promising technology for advancing preterm birth (PTB) research, pharmacology studies, and fertility technologies. [ABSTRACT FROM AUTHOR]

It is becoming increasingly common to use gold nanoparticles (AuNPs) protected by a heterogeneous mixture of thiolate ligands, but many ligand mixtures on AuNPs cannot be properly characterized due to the inherent limitations of commonly used spectroscopic techniques. Using ion mobility mass spectrometry (IM-MS), we have developed a strategy that allows measurement of the relative quantity of ligands on AuNP surfaces. This strategy is used for the characterization of three samples of mixed-ligand AuNPs: tiopronin:glutathlone (av diameter 2.5 nm), octanethiohdecanethiol (av diameter 3.6 nm), and tiopronin:11-mereaptoundecyl(poly ethylene glycol) (av diameter 2.5 nm). For validation purposes, the results obtained for tiopronin:glutathione AuNPs were compared to parallel measurements using nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) without ion mobility separation. Relative quantitation measurements for NMR and IM-MS were in excellent agreement, with an average difference of less than 1% relative abundance. IM-MS and MS without ion mobility separation were not comparable, due to a lack of ion signals for MS. The other two mixed-ligand AuNPs provide examples of measurements that cannot be performed using NMR spectroscopy. 10.1021/ac102175z

Matrix-assisted laser desorption/ionization-ion mobilitymass spectrometry (MALDI-IM-MS) was used to analyze low mass gold-thiolate fragments generated from thiolate-protected gold nanoparticles (AuNPs). This is the first report of using gas-phase structural separations by IMMS for the characterization of AuNPs, revealing significant structural variation between organic and gold-thiolate ionic species. Through the separation of background chemical noise, gold-thiolate ion species corresponding to fragments from the AuNP surface can be isolated. In the negative ion mode, many of these fragments correlate to capping structural motifs observed in the literature. In the positive ion mode, the fragment ions do not correlate to predicted structural motifs, but are nearly identical to the positive ions generated from the gold-thiolate AuNP precursor complexes. This suggests that energetic processes during laser deserption/ionization induce a structural rearrangement in the capping gold-thiolate structure of the AuNP, resulting in the generation of positively charged gold-thiolate complexes similar to the precursors of AuNP formation by reduction and negatively charged complexes more representative of the AuNP surface. 10.1021/ac100251d

The analysis of drinking water for lead, which has well-known health effects, is presented as an instructive example for undergraduate chemistry students. It allows the students to perform an experiment and evaluate to monitor risk factors and common hazard of everyday life.