Microplasma Technology and Its Applications in Analytical Chemistry

Abstract

This review article describes some existing microplasma sources and their applications in analytical chemistry. These microplasmas mainly include direct current glow discharge (DC), microhollow-cathode discharge (MHCD) or microstructure electrode (MSE), dielectric barrier discharge (DBD), capacitively coupled microplasmas (CCμPs), miniature inductively coupled plasmas (mICPs), and microwave-induced plasmas (MIPs). The historical development and recent advances in these microplasma techniques are presented. Fundamental properties of the microplasmas, the unique features of the reduced size and volume, as well as the advantageous device structures for chemical analysis are discussed in detail, with the emphasis toward detection of gaseous samples. The analytical figures of merit obtained using these microplasmas as molecular/elemental-selective detectors for emission spectrometry and as ionization sources for mass spectrometry are also given in this review article.     

Recent Progress in Chemiluminescence for Gas Analysis

Abstract

Chemiluminescence is frequently used as a powerful analytical tool for gas analysis. In this mini-review with 102 references, we summarize the recent advances in chemiluminescence-based analytical methodologies and their application in gas/volatile species analysis, mainly including applications of ozone-induced chemiluminescence, cataluminescence-based gas sensors and arrays, and dielectric barrier discharge–induced chemiluminescence for gas analysis. Efforts in the innovation of the methodologies, the exploration of new sensing materials, and the mechanism studies are discussed in detail.     

Recent advances in the research of inorganic nanotubes and fullerene-like nanoparticles

This minireview outlines the main scientific directions in tile research of inorganic nanotubes （1NT） and fullerene-like （IF） nanoparticles from layered compounds, in recent years. In particular, this review describes to some detail the progress in the synthesis of new nanotubes, including those from misfit compounds; core-shell and the successful efforts to scale-up the synthesis of WS2 multiwalt nanotubes. The high-temperature catalytic growth of nanotubes, via solar ablation is discussed as well. Furthermore, the doping of the 1F-MoS2 nanoparticles and its influence on the physiochemical properties of the nanoparticles, including their interesting tribological properties are briefly discussed. Finally, the numerous applications of these nanoparticles as superior solid lubricants and for reinforcing variety of polymers are discussed in brief.     

Recent advances on amphiphilic polymer-based fluorescence spectroscopic techniques for sensing and imaging

Abstract

Amphiphilic polymers (APs) characterized with excellent water solubility, biodegradability, biocompatibility, and low toxicity have become popular materials for biological sensing and imaging in the recent years. Among the several sensing and imaging techniques, fluorescence-based methods show distinct advantages and present unique opportunities to address challenges afforded by other techniques. This review covers five different types of APs (amphiphilic-conjugated polymers, amphiphilic polysaccharides, amphiphilic molecularly imprinted polymers, amphiphilic block copolymers, and amphiphilic polymeric nanoparticles) and their application for fluorescence spectroscopic sensing and imaging, in particular how techniques have been progressed over recent years. Afterwards, the applications of APs in the diagnosis and treatment of diseases, water safety and environmental monitoring has been discussed.     

Recent Progress on Infrared Photoacoustic Spectroscopy Techniques

Abstract

Analogous to most new methods in science, photoacoustic spectroscopy (PAS) grew out of an advance in technology, in this case the dramatic improvement in novel light sources, modulators, and acoustic detectors, as well as signal recovery electronics, which in turn was made possible by the development of modern PAS techniques. PAS is a promising technique that can be used to analyze and characterize a broad variety of objects (gaseous, solid, and liquid samples). In the present review, the recent development of infrared PAS limited to the general area of gas-phase analysis techniques since 1990 is summarized, with special emphasis on the development of new or enhanced analytical methodologies based on the use of the photoacoustic (PA) effect to improve the sensitivity of PAS by enhancing signal or reducing noise levels, with regard to PA systems, applications, and conclusions. The applications of these novel PA methods are mainly concerned with molecular spectroscopic, industrial, atmospheric, environmental, chemical and biological, and medical and clinical analysis. New prospects and challenges in various application fields of PAS technique are described.     

Preparation and Applications of Carbon-Based Fluorescent Nanothermometers

In recent years, carbon-based fluorescent nanomaterials have been developed rapidly in biology and biomedicine due to their high optical absorptivity, adjustable fluorescent emission, chemical stability, well biocompatibility, and low toxicity. Their applications in temperature sensing have become one of the research hotspots. In this review, the authors summarize and sort out the carbon-based fluorescent nanothermometers in the following work: 1) the types and temperature-response mechanism of carbon-based fluorescent nanomaterials are discussed; 2) the preparation methods of colorimetric fluorescent carbon-based thermometers are introduced; 3) the applications of single/double emission carbon-based fluorescent nanothermometers have been focused on. Finally, the authors give their own views on the future development direction of carbon-based fluorescent nanothermometers. This review can provide guidance for the design and application of novel carbon-based fluorescent nanothermometers.     

Microplasma-Based Detectors for Gas Chromatography: Current Status and Future Trends

Abstract: Microplasma is a useful detector for analyzing the effluent of gas chromato-graphy due to its remarkable capacity for portability, high sensitivity, and excellent multielement selectivity. Compared to classical detectors, microplasma detectors have the advantages of small size, low cost, and low energy consumption in design and operation. We aim to provide an overview of microplasma detectors and show their applications in various chemical analyses. The operational characteristics and analytical performance of different microplasma detectors, such as capacitively coupled microplasma, glow discharge microplasma, and microhollow-cathode microplasma, are presented in detail to reveal the current status of microplasma detectors for gas chromatography. In addition, several approaches for the design of microplasma are discussed and the future trends in the development of microplasma detectors are highlighted at the end of this review. Various applications of microplasma detectors for gas chromatography systems are also presented in this review.     

Toxicity and cellular uptake of gold nanoparticles: what we have learned so far?

Gold nanoparticles have attracted enormous scientific and technological interest due to their ease of synthesis, chemical stability, and unique optical properties. Proof-of-concept studies demonstrate their biomedical applications in chemical sensing, biological imaging, drug delivery, and cancer treatment. Knowledge about their potential toxicity and health impact is essential before these nanomaterials can be used in real clinical settings. Furthermore, the underlying interactions of these nanomaterials with physiological fluids is a key feature of understanding their biological impact, and these interactions can perhaps be exploited to mitigate unwanted toxic effects. In this Perspective we discuss recent results that address the toxicity of gold nanoparticles both in vitro and in vivo, and we provide some experimental recommendations for future research at the interface of nanotechnology and biological systems.     

Exploration of Displacement Reaction/Sorption Strategies in Spectrometric Analysis

Abstract

Displacement reactions are very popular in nature, ranging from texbook knowledge of the Zn-CuSO₄ system to modern functional nucleic acid–involved metal ion displacement. Though synthetic chemistry harvests a lot from displacement reactions, analytical chemistry benefits greatly from various displacement reaction strategies, such as sensitivity improvement. In particular, the use of indicator displacement assay for new sensor development is of great interest worldwide. In this review, we summarize the advances in utilization of displacement reactions for improved spectrometric analysis. The main contents include displacement-based preconcentration schemes for trace metal analysis by analytical atomic spectrometry, indicator displacement assays focusing on the use of advanced nanomaterials, and displacement immunoassays using spectrometric measurements, with 117 references.     

Lanthanide-Sensitized Luminescence as a Promising Tool in Clinical Analysis

Abstract

The recent applications and novelties of lanthanide-sensitized luminescence (LSL) as a detection technique in clinical analysis are here reviewed. In LSL, lanthanide ions form complexes with organic compounds; in these complexes, the energy absorbed by the organic chromophore (usually the analyte) at its characteristic excitation wavelength is transferred to a triplet state of the molecule and then transferred to a resonance level of the lanthanide ion, which finally emits luminescence at its particular emission wavelength. The characteristics of this process will be reviewed and particular attention will be paid to the development of automatic methods of analysis, fluorescence probes, or flow-through optosensors, due to their potential applications in clinical analysis. A critical discussion of the advantages and handicaps of each analytical method is done and the trends of analytical chemistry in this research field are also presented.     

Investigation of Bioimpacts of Metallic and Metallic Oxide Nanostructured Materials: Size,Shape, Chemical Composition,and Surface Functionality: A Review

Nanotechnology is set to impact a wide range of various fields, including medicine, materials technology, environmental sciences, and engineering/manufacturing. Nanoparticles are categorized depending on their size, composition, shape, and surface functionality. Due to the excessive growth of nanostructured materials (NSMs) in production and industrial applications, human and environmental exposure to them and their possible toxicity issues are inevitable. The main objective of this review is to study NSMs, in particular metallic and metallic oxide nanoparticles, and properties that have a determinative role in their bioimpacts. Nevertheless, the main focus is to provide an overview of NSMs toxicology. Medical and environmental applications of the NSMs are discussed here. Also, key factors on the toxicity of the nanoparticles such as shape, size, chemical composition, and surface functionality are discussed. Finally, toxicity of the nanoparticles is going to be highlighted, and relevant studies are critically compared. This review gives a broad scientific view for improving the functional efficiency of nanomaterials while mitigating their possible adverse and unintended effects on biological systems.     

Laser Ablation Inductively Coupled Plasma Mass Spectrometry: Principles and Applications

Abstract

The application of laser ablation inductively plasma mass spectrometry (LA‐ICP‐MS) to the determination of major, minor, and trace elements as well as isotope‐ratio measurements offers superior technology for direct solid sampling in analytical chemistry. The advantages of LA‐ICP‐MS include direct analysis of solids; no chemical dissolution is necessary, reduced risk of contamination, analysis of small sample mass, and determination of spatial distributions of elemental compositions. This review aims to summarize recent research to apply LA‐ICP‐MS, primarily in the field of environmental chemistry. Experimental systems, fractionation, calibration procedures, figures of merit, and new applications are discussed. Selected applications highlighting LA‐ICP‐MS are presented.     

纳米尺度下的局域场增强研究进展

金属纳米颗粒的等离激元共振引起的局域场增强效应,对显微成像、光谱学、半导体器件、非线性光学等诸多领域都具有极大的应用潜力。尤其是在光学纳米材料领域,通过亚波长金属纳米颗粒与电介质的组合引起局域场增强效应,提高了纳米材料的光学性能,并促进纳米材料在光学领域的应用。本文主要综述几种常见纳米结构所产生的局域场增强效应及其应用,详细介绍并总结了金属纳米材料的不同结构参数与局域场增强的关系及局域场增强在非线性光学、光谱学、半导体器件等领域的应用。未来,随着对金属纳米材料的研究愈发深入,局域场增强的应用将更加广泛,这将对诸多领域的发展产生重要影响。     

Engineering of SERS Substrates Based on Noble Metal Nanomaterials for Chemical and Biomedical Applications

Abstract

Surface-enhanced Raman scattering (SERS) has attracted great interest due to its remarkable enhancement, excellent sensitivity, and the “fingerprinting” ability to produce distinct spectra for detecting various molecules. Noble metal nanomaterials have usually been employed as SERS-active substrates because of their strong SERS enhancement originated from their unique surface plasmon resonance (SPR) properties. Because the SPR property depends on metal material's size, shape, morphology, arrangement, and dielectric environment around metal nanostructures, the key to wider applications of SERS technique is to develop plasmon-resonant structures with novel geometries to enhance Raman signals and to control the periodic ordering of these structures over a large area to obtain reproducible Raman enhancement. This review presents a general view on the theory background of SERS effect and several basic concepts and focuses on recent progress in engineering metallic nanostructures with various morphologies using versatile methods for improving SERS properties. Their potential applications in the field of chemical detection and biological sensing are overviewed.     

Glow Discharge as a Tool for Surface and Interface Analysis

Abstract

This review article focuses on the analytical capabilities of glow discharge optical emission spectrometry (GD‐OES) and mass spectrometry (GD‐MS) to perform compositional depth profiling (GD‐CDP). The properties of the Grimm‐type glow discharge as well as basic processes of sputtering are described and their influence on the GD as a surface and interface analytical tool are discussed. A series of examples from recent literature ranging from computer hard disks to molecular monolayers on copper substrates are presented to illustrate the excellent depth resolution that can be achieved with GD surface analytical techniques. The conditions for obtaining nanometer or even atomic‐layer depth resolution are discussed. Following this introduction is the possibilities of the technique a selection of applications principally chosen from our laboratories, demonstrating that GD‐OES and GD‐MS can be successfully employed as an analytical tool assisting the development of new materials and coatings. The applications cover common industrial tasks such as heat treatments, studies of diffusion processes at interfaces, and electrochemical depositions for biocompatible material. However, limitations and known artifacts are also discussed.     

Gold and Silver Nanomaterial‐Based Optical Sensing Systems

Gold and silver nanomaterials (NMs) such as nanoparticles (NPs) and nanoclusters (NCs) possessing interesting optical properties have become popular sensing materials. With strong surface plasmon resonance (SPR) absorption, extraordinary stability, ease in preparation, conjugation, and biocompatibility, Au NPs are employed to develop sensitive and selective sensing systems for a variety of analytes. However, small sizes of Au and Ag NCs with interesting photoluminescence (PL) properties are used in many PL‐based sensing systems for the detection of important analytes. In addition, many bimetallic AuM NMs possessing strong catalytic activity are used to develop highly sensitive fluorescent sensors. This review article is categorized in four sections based on the NMs used in the sensing systems, including Au NPs, bimetallic AuM NMs, Au NCs, and DNA–Ag NCs. In each section, synthetic strategies and optical properties of the NMs are provided briefly, followed by emphasis on their analytical applications in the detection of small molecules, metal ions, DNA, proteins, and cells. Current challenges and future prospects of these NMs‐based sensing systems will be addressed.     

Nanomaterials in Cerebrovascular Disease Diagnose and Treatment

Cerebrovascular diseases (CVDs) are among the most serious diseases with high mortality and disability rates. The prevalent diagnosis and treatment methods of CVDs include imaging and interventional therapy. With the development of nanotechnology, large numbers of nanomaterials have been applied to the diagnosis and treatment of CVDs, mainly including carbon nanotubes, quantum dots, fullerenes, and dendrimers. In this review, the applications of nanomaterials in the field of diagnosis and treatment of CVDs, mainly including drug target delivery, imaging, therapy, endovascular treatment, and angiogenesis, are summarized. The applications of nanomaterials in the field of CVD are almost in the laboratory, and more effort is needed for clinical translation. The aim of this review is to provide useful information for future research and equipment development.     

Recent Analytical Applications of Molecular Spectroscopy in Bioorganometallic Chemistry—Part I: Metal Carbonyls

Abstract: This is the first part of a two-part review on the analytical applications of molecular spectroscopy in bioorganometallic chemistry since 2005. In this case, radiopharmaceutical studies are included and the review is focused particularly on biological molecules labeled with metal carbonyl fragments.     

Analytical Assessments of Gallstones and Urinary Stones: A Comprehensive Review of the Development from Laser to LIBS

Abstract

Laser-induced breakdown spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of various kinds of materials (solid, liquids, and gases) and its applications are growing rapidly and continue to extend to include a broad variety of biological materials. Its application is suited particularly for urinary stones and gallstones bulk analysis and microanalysis because investigation of the spatial distribution of matrix and trace elements can help to explain their emergence and growth. Therefore, we review the application of LIBS for the analysis of different kinds of gallstones and urinary stones. In brief, we also describe the history, fundamentals, advantages, and disadvantages of LIBS and its potential for spectrochemical analysis of gallstones and kidney stones. We also emphasize the applications of different kinds of lasers in urology, particularly the laser ablation of gallstones and urinary stones and its recent progress. We also summarize and compare the analytical figures of merits of analytical techniques that are commonly used to characterize and/or analyze stones.