The increasing use of engineered nanoparticles (NPs) in consumer and biomedical products has raised concern over their potential accumulation, transformation, and toxicity in biological systems. Accurate analytical methods are essential to detect, characterize, and quantify NPs in complex biological matrices. Inductively coupled plasma mass spectrometry (ICP-MS) has emerged as a leading technique due to its high sensitivity, elemental selectivity, and quantitative capabilities. This review critically evaluates recent advances (from January 2020 onward) in ICP-MS-based methods for analysis of NPs in biological samples. Two main strategies are discussed: single-particle ICP-MS (spICP-MS) and hyphenated techniques coupled to ICP-MS. spICP-MS allows direct determination of particle size, concentration, and metal content at environmentally relevant levels. It is the most widely used approach and is therefore examined in greater detail, with attention to extraction procedures, particle types, sample matrices, and inherent limitations. Advances in laser ablation spICP-MS for tissue imaging and spatially resolved NPs detection are also covered. Methods using hyphenated techniques, such as hydrodynamic chromatography, size-exclusion chromatography, capillary electrophoresis, Taylor dispersion analysis, and field-flow fractionation, are increasingly employed to address limitations spICP-MS. These approaches can provide enhanced insight into particle size distributions, aggregation behavior, and interactions with complex sample matrices. This review offers a comparative evaluation of both single-particle and hyphenated methods, discussing their respective advantages and limitations. Emphasis is placed on the complementarity of these techniques and how their combined use can offer a more complete understanding of NPs' fate in biological systems.

A novel methodology for investigating the behavior of nanoparticles in their mixtures in aqueous high-ionic strength conditions is presented in this work. Our approach utilizes Taylor dispersion analysis in capillaries connected to inductively coupled plasma mass spectrometry (ICP-MS) to probe metal-derived nanoparticles. This methodology simultaneously distinguishes between different kinds of nanoparticles and accurately determines their essential parameters, such as hydrodynamic size, diffusion coefficient, and elemental composition. Moreover, the isotope-specific ICP-MS detection allows for unique targeting of the fate of isotopically enriched nanoparticles. The complexity of our methodology opens the way for studying barely explored areas of interparticle interactions or unequivocal characterization of one type of nanoparticle in complex mixtures without any need for calibration as well as labor-consuming sample preparation.

This unique study provides information on Cr species and their distribution in periprosthetic tissues of patients with metal-on-polyethylene joint implants. Co-Cr-Mo alloy has been widely used in joint replacement and represents a source of metal derived species. In the case of chromium, previous studies on periprosthetic tissues revealed mainly Cr(III) distribution, whereas the potential release of carcinogenic Cr(VI) species has been still a subject of debate. Here, an analytical approach utilizing speciation and fractionation was developed to analyze periprosthetic tissue samples collected from wide range of patients with failed total hip or knee replacements. The results reveal that Cr(III) is mainly released in the form of insoluble CrPO4 and Cr2O3 particles. The highest Cr contents were found in periprosthetic tissues of patients suffering from aseptic loosening and having more Cr-based implants in the body. Cr species penetrated tissue layers, but their levels decreased with the distance from an implant. The detailed speciation/fractionation study carried out using the set of consecutive periprosthetic tissues of a patient with extensive metallosis showed the presence of trace amounts of free Cr(III), nanoparticles, and metal-protein complexes, but the majority of Cr still occurred in CrPO4 form. Carcinogenic Cr(VI) species were not detected. Up to date, there is no published human tissue study focused on the detailed speciation of both soluble and insoluble Cr-based species in the context of failing total hip and knee replacements.

Oxaliplatin represents a platinum-based cancerostatic drug that is widely used for the treatment of various types of cancer. There are two main platinum-containing impurities, impurity B and C, that can be formed as side products at very low concentrations. Their effect on biological systems can be like the oxaliplatin itself; however, this has not been fully investigated since there is a lack of methods for their determination in ultralow con-centrations. In our work, we present a method for ultra-trace determination of oxaliplatin impurities B and C, and oxaliplatin itself, using online sweeping preconcentration micellar electrokinetic chromatography coupled with inductively coupled plasma mass spectrometry (MEKC-ICP-MS). This is the first application of online pre-concentration with MEKC-ICP-MS to improve the detection limits of analytes. Under the optimal conditions, 25 mM sodium phosphate buffer at pH 2.15 with 175 mM SDS, and an injection time of 90 s at 50 mbar, baseline separation of all components within 6 min was achieved. The sweeping-MEKC-ICP-MS method was fully vali-dated in terms of linearity, limits of detection and quantification, trueness, precision, and reproducibility of migration times. Limits of detection of 2, 1, and 3 ng mL(-1) for impurity B, impurity C, and oxaliplatin, respectively, were obtained, which are 3,500-, 1,700-, and 2,100-fold lower than those for a MEKC-UV method also developed and validated as a part of this work. It also represents the detection of 98 femtograms of the impurity C (or 227 attomol of Pt) per injection. The sweeping-MEKC-ICP-MS method further benefits from a wide dynamic range up to six orders of magnitude (0.01-1,000 mu g mL(-1) for oxaliplatin) with coefficients of deter-mination greater than 0.9989. ICP-MS provides characteristic element/isotope-specific and structure-independent detection. ICP-MS helped identify the co-separated impurity B counter-ion that can be wrongly assigned as the platinum-based impurity B using standard UV detection. Finally, the validated sweeping-MEKC-ICP-MS method was applied to the analysis of oxaliplatin samples with variable impurities concentrations (0.06-1.0%). The trueness and precision ranged between 76 and 115% and 2-19%, respectively. This method allows the accurate determination of oxaliplatin impurities from 0.0003% levels; therefore, it could be used in routine pharmaceutical laboratories for quality control purposes.

The aim of our work was to develop a low-cost, portable device for the fast and easy determination of total protein content by using PDMS-based lab-in-a-syringe technology with removal of 3D-printed channels. We proposed two designs with a one-step PDMS curing and a two-step PDMS-curing fabrication procedure. The one-step PDMS microdevices were found to be the best in the view of preparation, repeatability, and stability of the reagent. This design was then applied for the determination of total protein content in biomedical products using the Bradford assay.

Introduction Capillary electrophoresis (CE) hyphenated to inductively coupled plasma mass spectrometry (ICPMS) as an element-specific detector represents an interesting and beneficial tool for many applications. Nowadays, CE-ICP-MS is used primarily for speciation analysis, metal-ligand interaction studies including metal-based nanoparticles, as recently reviewed [1]. However, CE-ICP-MS has the potential to touch also other fields by taking account of other advantages of CE, e.g. in chiral separations or in online preconcentration methodologies.

In this work, interactions of carboxylated core shell magnetic nanoparticles with polymyxin B sulfate were studied by connecting capillary electrophoresis with inductively coupled plasma mass spectrometry. The interaction was probed by affinity mode of capillary electrophoresis with 25 mM phosphate buffer at physiological pH. 54Fe, 56Fe, 57Fe, 34S, and 12C isotopes were used to monitor the migration of an electroosmotic flow marker and the interaction of the nanoparticles with polymyxin B. The analysis of interaction data showed two distinct interaction regions, one with low polymyxin B concentration, the second with high polymyxin B concentration. These regions differed in the strength of the interaction, 1.49 × 107 M-1 and 1.60 × 104 M-1, and in the stoichiometry of 0.7 and 3.5, respectively. These differences can be explained by the decrease of electrostatic repulsion between nanoparticles caused by polymyxin B. This is also in agreement with the nanoparticles peak shapes: sharp for low polymyxin B concentrations and broad for high polymyxin B concentrations.

The aim of this study was to develop a method for the separation of oxaliplatin enantiomers at attomolar concentration levels. A combination of capillary electrophoresis and inductively coupled plasma mass spectrometry was chosen due to their unique characteristics, including fast and easy modification of separation selectivity, and significant limits of detection and linearity. In the first step, we optimized conditions for the separation of oxaliplatin enantiomers including background electrolyte composition and concentration, pH, and type and concentration of the chiral selector. Under optimal conditions, sodium borate buffer pH 9.5, ionic strength 40 mmol L-1, with 60 mg mL(-1) sulfated beta-cyclodextrin, separation was obtained with a resolution of 2.0. This electrolyte system was then used in the 'in-house' connection of capillary electrophoresis with inductively coupled plasma mass spectrometer. In this instance, separation lasted for 9.5 min. Calibrations were linear in the range of 0.1-500 mu g mL(-1) with R-2 of 0.9999. LOD and LOQ values were of 64 ng mL(-1 )and 116 ng mL(-1) of oxaliplatin, respectively. This represents detection of 49 fg or 125 attomol of oxaliplatin enantiomers in the capillary electrophoresis injected sample zone. Finally, the method was successfully applied for detection of oxaliplatin enantiomers in spiked urine samples.

The contamination of water represents a major problem in many parts of the world. Endocrine disrupting compounds belong to the water contaminants and affect, besides other things, hormonal equilibrium in the living organisms. Such compounds are of different chemical structures and there is a demand for their fast determination in water samples. In our work, we focused on the development of a simple and fast method for separation and determination of five model hormone antagonists, exemestane, toremifene, letrozole, anastrozole, and mifepristone, by micellar electrokinetic chromatography. Within the best conditions, 50 mM sodium borate pH 9.5, 50 mM SDS, 15% 1-propanol, 20 kV, the separation of all the compounds lasted 8 min. The method was successfully validated with LODs of 1.2–7.7 µg mL−1, LOQs of 4.0–25.6 µg mL−1 and intraday repeatability of peak areas of 0.8–1.1%. Moreover, it was applied to the analysis of spiked water samples from a local waste-water treatment plant using SPE as a pretreatment step.

The stacking effect on carboxylated magnetite core-shell nanoparticles using sodium borate buffer pH 9.5 as the background electrolyte is presented. The ionic strength of the background electrolyte ranged from 5 to 100 mM, and the ionic strength of a sample zone ranged from 5 to 100 mM. Moreover, water was used as the sample dispersant. Both stacking and de-stacking effects were observed when conductivities of the sample zone and the background electrolyte differed. An explanation of carboxylated magnetic core-shell nanoparticles behavior was suggested based on the Derjaguin-Landau-Verwey-Overbeek theory supposing that the aggregation point is defined by the energetic barrier as the sum of energies given by electrostatic interactions and Van der Waals interactions. Moreover, the stacking conditions were applied for the evaluation of the lowest detectable dilution of magnetic nanoparticles. The carboxylated magnetic nanoparticles were dispersed in 10 mM borate/NaOH pH 9.5 and injected for 60 s to the background electrolyte composed of 100 mM borate/NaOH pH 9.5 that allowed the detection of 100-fold diluted nanoparticles.

In our work, we introduced a novel concept of the lab-in-a-syringe tests. We solved the problem of detection in already published LIS tests by putting all the reaction and detection pads directly into the syringe barrel. We also used more layers to make the results visible for users. Two detection layouts: (i) with using rounded pads based detection, and (ii) with using rectangular detection pads, were studied. As the proof of concept, we studied the determination of Ni(II) using dimethylglyoxime as the reagent and blocking of the interference of Fe(II). The calibrations for Ni(II) at the optimal conditions has excellent R-2 of 0.998 with production costs of 0.2 USD per one test.

Online electrokinetic preconcentration of magnetite core/carboxylic shell nanoparticles (MNPs) was studied by capillary electrophoresis using reversed and suppressed electroosmotic flow (EOF). 50 mM sodium borate pH 9.5 was used as a background electrolyte. CTAB additive was used to reverse EOF and commercial polyvinylalcohol (PVA)-coated capillaries were used for EOF suppressed studies. Analyses in PVA-coated capillaries were more reproducible and therefore, the setup was further optimized in terms of water plug injection time, sample injection time, and voltage. Within the optimal conditions, the MNPs dispersed in water are electrokinetically loaded into BGE consisting of 50 mM sodium borate pH 9.5 using -10 kV for 120 s. In comparison with the hydrodynamic injection of 5 s by 50 mbar, the electrokinetic injection allows 860-fold preconcentration of MNPs. (C) 2017 Elsevier B.V. All rights reserved.

In this work, we present a layer-by-layer approach for modification of capillary inner wall for capillary electrophoresis of biologically active compounds. The layer-by-layer coating was optimized using polybrene and polystyrenesulphonate. Further modification of the capillary by nanoparticles modified with polystyrenesulphonate was also evaluated.

Tato diplomova prace se zabýva charakterizaci nanoobjektů pomoci kapilarnich elektromigracnich technik. V prvnich kapitolach se věnuje obecným vlastnostem nanocastic a jejich použiti v medicině nebo životnim prostředi. Dalsi kapitoly popisuji využiti magnetických nanocastic, jejich připravu a možnosti stabilizace. Ve druhe casti teorie jsou popsany fyzikalni děje v kapilarnich elektromigracnich technikach, elektroosmotický tok, instrumentace v kapilarni elektroforeze a typy elektromigracnich technik. Posledni cast teorie se zabýva proteiny použitými v experimentalni casti. Experimentalni cast prace ukazuje využiti kapilarni elektroforezy pro separaci magnetitových (Fe3O4) nanocastic, jejich chovani v kapilarni elektroforeze v různých zakladnich elektrolytech a možnost studia interakci mezi magnetitovými nanocasticemi a různými proteiny (hovězi serový albumin, -laktoglobulin, lysozym, cytochrom C, lidský serový albumin a křenova peroxidaza) pomoci afinitni kapilarni elektroforezy. Cilem prace bylo ukazat, jak může být kapilarni elektroforeza využita ke studiu interakci nanocastic s biomolekulami, výpoctu interakcnich konstant vzniklých komplexů, urceni stechiometrických poměrů mezi nanocastici a ligandem a odhadu typů interakci.