Analyte Losses Research Articles

Rapid detection of five anesthetics in tilapias by in vivo solid phase microextraction coupling with gas chromatography-mass spectrometry

The concentration of five rapidly metabolized anesthetics in living tilapias was determined in this study, by the presented method coupling in vivo solid phase microextraction (SPME) to gas chromatography-mass spectrometry (GC-MS), which was the first time that in vivo sampling method was adapted in detecting the anesthetic residue in the living aquatic product. The analytical performance of the developed method was evaluated in homogenized tilapia dorsal muscle, and the results demonstrated that the present method possessed low detection limits 1.7–9.4ngg−1), wide linear ranges (10 or 30–5000ngg−1), and satisfactory reproducibility (relative standard deviations no more than 8.1% and 10.8% for inter-fiber and intra-fiber assays, respectively). Standard curves were established in homogenized tilapia dorsal muscle for calibrating in vivo SPME in living tilapias. And the concentrations determined by in vivo SPME were close to those determined by the liquid extraction. By using the present method, one anesthetic residue was detected above the detection limit in tilapias from the local markets. Comparing to traditional methods, the present one exhibited superior time-efficiency and cost performance, as the extraction time was only ten minutes, which was short to successfully avoid the possible loss of analytes caused by elimination and sample storage. In addition, owing to the time-efficiency of the present method, the elimination of the anesthetics in tilapias was traced successfully in the laboratory.

A new method for quasi-reagent-free biomonitoring of mercury in human urine

A novel analytical method for sampling and extraction of mercury (Hg) from human urine is presented in this work. The method is based on selective accumulation and separation of Hg from fresh urine sample onto active nanogold-coated silica material by highly efficient solid-phase extraction. After thermal desorption of Hg from the extractant, detection is performed by atomic fluorescence spectrometry (AFS). The feasibility and validity of the optimized, quasi-reagent-free approach was confirmed by recovery experiments in spiked real urine (recovery rate 96.13 ± 5.34%) and by comparison of found Hg concentrations in real urine samples - originating from occupationally exposed persons – with values obtained from reference methods cold vapor - atomic absorption spectrometry (CVAAS) and cold vapor - atomic fluorescence spectrometry (CV-AFS). A very good agreement of the found values reveals the validity of the proposed approach. The limit of detection (LOD) was found to be as low as 0.004 μg Hg L−1 and a high reproducibility with a relative standard deviations ≤4.2% (n = 6) is given. Moreover, storage of the samples for up to one week at an ambient temperature of 30 °C reveals no analyte losses or contamination. In conclusion, the proposed method enables easy-to-handle on-site extraction of total Hg from human urine ensuring at the same time reagent-free sample stabilization, providing quick and safe sampling, which can be performed by untrained persons.

Evolution of novel sorbents for effective clean-up of honeybee matrix in highly toxic insecticide LC/MS/MS analysis

Highly toxic insecticides (HTIs) belonging to different chemical groups are dangerous to pollinating organisms, even in sublethal doses. An important objective of this study was to develop a method to determine over fifty HTIs at very low concentrations in the bee matrix. The novelty of this research involved obtaining extract completely free from beewaxes, lipids and proteins using EMR-lipid (enhanced matrix removal-lipid), chitin and Z-Sep+ (zirconium oxide and C18 dual-bonded to silica) as clean-up sorbents. Different parameters, such as weight of bees, extraction solvent, and freezing time were evaluated. Determinations were made using liquid chromatography-tandem mass spectrometry (LC-MS/MS). EMR-lipid allows for removing most of the fatty co-extracts and increases the overall performance of the method by reducing the matrix effects (ME) without significant analyte loss. The established modified QuEChERS method based on 1% acetic acid in acetonitrile extraction followed by EMR-lipid clean-up was validated at three different spiking levels (0.001, 0.01 and 0.1mgkg−1). Precision, calculated as relative standard deviation (RSD), was below 20%. The proposed method was used to determine sublethal doses of these insecticides in real samples of dead honeybees.

Determination of cinnamaldehyde, carvacrol and thymol in feedstuff additives by pressurized liquid extraction followed by gas chromatography–mass spectrometry

Specific blends of essential oils (BEOs) are promising substitutes for antibiotics to promote livestock performance and to reduce the incidence of intestinal disorders. Microencapsulation of BEOs has shown to improve their stability, bioavailability and to control their release rate once they are added to the feedstuff. The development and validation of a method for determining essential oil components such as carvacrol, thymol and cinnamaldehyde in a microencapsulated material used as feed additive is presented. Analytes were extracted from feed additives and feedstuff by pressurized liquid extraction (PLE) with methanol at 50°C for 5min. Methanol provided good recovery values and cleaner extracts than other polar organic solvents tested. However, for certain kind of composite additives ethyl acetate showed to be a better option because trans-cinnamaldehyde undergoes chemical reaction in methanol. Then PLE extracts were analysed by gas chromatography coupled to ion trap mass spectrometry in selected ion storage (SIS) mode. The analyte stability and the absence of analyte losses during the PLE process was checked by a recovery study. Also, the matrix effect was studied to assess accuracy. Recovery values were between 85 and 115% in most cases. Intra- and inter-day relative standard deviation values were less than 4 and 14%, respectively. Finally, the developed method was applied to the analysis of a microencapsulated feed additive, several composite feed additive samples containing microencapsulated BEOs and a spiked feedstuff, for quality control and in stability studies.

A biotin enrichment strategy identifies novel carbonylated amino acids in proteins from human plasma

Protein carbonylation is an irreversible protein oxidation correlated with oxidative stress, various diseases and ageing. Here we describe a peptide-centric approach for identification and characterisation of up to 14 different types of carbonylated amino acids in proteins. The modified residues are derivatised with biotin-hydrazide, enriched and characterised by tandem mass spectrometry. The strength of the method lies in an improved elution of biotinylated peptides from monomeric avidin resin using hot water (95°C) and increased sensitivity achieved by reduction of analyte losses during sample preparation and chromatography. For the first time MS/MS data analysis utilising diagnostic biotin fragment ions is used to pinpoint sites of biotin labelling and improve the confidence of carbonyl peptide assignments. We identified a total of 125 carbonylated residues in bovine serum albumin after extensive in vitro metal ion-catalysed oxidation. Furthermore, we assigned 133 carbonylated sites in 36 proteins in native human plasma protein samples. The optimised workflow enabled detection of 10 hitherto undetected types of carbonylated amino acids in proteins: aldehyde and ketone modifications of leucine, valine, alanine, isoleucine, glutamine, lysine and glutamic acid (+14Da), an oxidised form of methionine - aspartate semialdehyde (−32Da) - and decarboxylated glutamic acid and aspartic acid (−30Da). Biological significanceProteomic tools provide a promising way to decode disease mechanisms at the protein level and help to understand how carbonylation affects protein structure and function. The challenge for future research is to identify the type and nature of oxidised residues to gain a deeper understanding of the mechanism(s) governing carbonylation in cells and organisms and assess their role in disease.

Development of Liquid Chromatography Separation and a Solid-Phase Extraction Method for Phenoxy Alkanoic Acid Herbicides in Water

A sensitive solid phase extraction enhancement reversed-phase high-performance liquid chromatography (RPHPLC) determination was adopted for the separation and the determination of phenoxy alkanoic acids herbicides in water. The analytes that have been concentrated were eluted and separated on a C18 analytical column at a flow of 1 mL min-1 and were determinate by measuring their UV absorption at 220 nm. A solid phase extraction (SPE) method was developed for the analysis of seven phenoxy alkanoic acid herbicides. The effects of the sample volume, sorbent mass and pH on the recoveries of these herbicides were investigated. Sample volume under to 1000 mL could be handled without any loss of analytes. The recoveries were dependent of sample pH in the range >80% and were achieved with pH=3 using 5 mL of methanol as desorption solvent. These acid herbicides were determined simultaneously using this method with good linearity (R2>0.998). The developed method SPE/RP-HPLCUV permitted the determination of phenoxy alkanoic aids in distilled water down to a level of 0.17 ng L-1 showing satisfactory recovery (>85%) for 1 L samples. The developed method was evaluated by analysis of surface water spiked at 1 μg L-1, so this method is suitable for detecting herbicide residues of sub-parts-per-billion levels in surface water.

Influences of relative humidities and temperatures on the collection of C2-C5 aliphatic hydrocarbons with multi-bed (Tenax TA, Carbograph 1TD, Carboxen 1003) sorbent tube method

Volatile organic compounds (VOCs) are measured with sorbent tubes followed by thermal desorption (TD) analysis. Water vapor in the atmosphere affects sampling breakthrough and results in low collection efficiency. This paper reports the effect of relative humidity (RH) and temperature on the collection of 57 ozone precursors with a multi-bed tube composed of three different strengths of adsorbents (Tenax TA, Carbograph 1 TD, and Carboxen 1003). Unacceptable breakthrough values for volatile C2-C5 aliphatic compounds were observed under high (>60%) RHs. The breakthrough volumes (BV) for C2 aliphatic compounds were reduced 13–22 fold under 90% RH. Dry-purge with inert helium gas removes excessive water content before the TD analysis but also causes a maximum of 40% loss of target analytes. Condensation is another pathway for water retention. The tube temperature should be regulated at 5–10 °C above the air temperature to minimize condensation under RHs >30%.

Simultaneous extraction of polycyclic aromatic hydrocarbons through the complete dissolution of solid biological samples in sodium hydroxide/urea/thiourea aqueous solution

In order to precisely and simultaneously extract polycyclic aromatic hydrocarbons (PAHs) for measurement using a high performance liquid chromatography-fluorescence detector (HPLC-FL), a novel sample preparation method was developed. This method is based on the complete and fast dissolution of biological samples in a new non-alcoholic alkaline medium. A solution composed of NaOH/urea/thiourea at an optimized ratio was used for complete dissolution of approximately 0.25g dried fish samples within 20min. The proposed method was conducted at 10°C and under atmospheric pressure to obtain a stable and highly homogeneous solution, without the need for microwaves or any other apparatus. This process operates at considerably lower temperature than conventional methods and provides an opportunity to simultaneously extract the target analytes from their matrices by adding the extracting solvent in the initial steps of the dissolution; this process greatly reduced the time of analysis and the loss of analytes via vaporization. Several key parameters were identified and their effects on precision and extraction recoveries were investigated. Linearity over a calibration range of 1.0–100 and 2.5–100ngg−1 was achieved, with high coefficients of determination (r2) ranging between 0.9987 and 0.9998. Based on relative standard deviations (n=5), the intra-day and inter-day precisions of the spiked PAHs were found to be better than 3.1% and 3.2%, respectively, at a concentration level of 25ngg−1. The recoveries of PAH from spiked marine fish tissues and shrimp samples were in the range of 90.6%–100.4%. The spiked samples were also treated with the alcoholic alkaline and Soxhlet extraction methods in order to provide a comparison.

Comparing adsorption of bisphenol A and similar compounds in aqueous solution by syringe filters

Analyte loss during syringe filtration is often overlooked in quantitative analyses. Bisphenol A and similar compounds are being extensively examined for their toxicity. This study serves to characterize common syringe filters and their effects on analytical results. The adsorbance of bisphenol A and similar compounds by filter media made from cellulose acetate, nylon, and polytetrafluoroethylene was examined using UV–Vis spectroscopy. Samples of bis(4-hydroxydiphenyl)methane, bis(4-hydroxyphenyl)sulfone, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 4,4′-(propane-2,2-diyl)diphenol, 4-cumylphenol, and phenol were studied. Solutions were analyzed before and after filtration. Filter composition significantly affected analyte concentrations in the filtrate solutions.

Colloidal Mechanisms of Gold Nanoparticle Loss in Asymmetric Flow Field-Flow Fractionation.

Flow field-flow fractionation is a powerful method for the analysis of nanoparticle size distributions, but its widespread use has been hampered by large analyte losses, especially of metal nanoparticles. Here, we report on the colloidal mechanisms underlying the losses. We systematically studied gold nanoparticles (AuNPs) during asymmetrical flow field-flow fractionation (AF4) by systematic variation of the particle properties and the eluent composition. Recoveries of AuNPs (core diameter 12 nm) stabilized by citrate or polyethylene glycol (PEG) at different ionic strengths were determined. We used online UV-vis detection and off-line elementary analysis to follow particle losses during full analysis runs, runs without cross-flow, and runs with parts of the instrument bypassed. The combination allowed us to calculate relative and absolute analyte losses at different stages of the analytic protocol. We found different loss mechanisms depending on the ligand. Citrate-stabilized particles degraded during analysis and suffered large losses (up to 74%). PEG-stabilized particles had smaller relative losses at moderate ionic strengths (1-20%) that depended on PEG length. Long PEGs at higher ionic strengths (≥5 mM) caused particle loss due to bridging adsorption at the membrane. Bulk agglomeration was not a relevant loss mechanism at low ionic strengths ≤5 mM for any of the studied particles. An unexpectedly large fraction of particles was lost at tubing and other internal surfaces. We propose that the colloidal mechanisms observed here are relevant loss mechanisms in many particle analysis protocols and discuss strategies to avoid them.

Gas chromatography fractionation platform featuring parallel flame-ionization detection and continuous high-resolution analyte collection in 384-well plates

Gas chromatography (GC) is a superior separation technique for many compounds. However, fractionation of a GC eluate for analyte isolation and/or post-column off-line analysis is not straightforward, and existing platforms are limited in the number of fractions that can be collected. Moreover, aerosol formation may cause serious analyte losses. Previously, our group has developed a platform that resolved these limitations of GC fractionation by post-column infusion of a trap solvent prior to continuous small-volume fraction collection in a 96-wells plate (Pieke et al., 2013 [17]). Still, this GC fractionation set-up lacked a chemical detector for the on-line recording of chromatograms, and the introduction of trap solvent resulted in extensive peak broadening for late-eluting compounds. This paper reports advancements to the fractionation platform allowing flame ionization detection (FID) parallel to high-resolution collection of a full GC chromatograms in up to 384 nanofractions of 7s each. To this end, a post-column split was incorporated which directs part of the eluate towards FID. Furthermore, a solvent heating device was developed for stable delivery of preheated/vaporized trap solvent, which significantly reduced band broadening by post-column infusion. In order to achieve optimal analyte trapping, several solvents were tested at different flow rates. The repeatability of the optimized GC fraction collection process was assessed demonstrating the possibility of up-concentration of isolated analytes by repetitive analyses of the same sample. The feasibility of the improved GC fractionation platform for bioactivity screening of toxic compounds was studied by the analysis of a mixture of test pesticides, which after fractionation were subjected to a post-column acetylcholinesterase (AChE) assay. Fractions showing AChE inhibition could be unambiguously correlated with peaks from the parallel-recorded FID chromatogram.

Investigation of analyte losses using microwave-assisted sample digestion and closed vessels with venting

Microwave-assisted sample digestion using closed vessels is becoming the standard for trace analysis because contamination and losses can be better controlled. Gases are generated during digestion and there is an increment of the internal vessel pressure. Consequently, vessels venting may occur depending on the design of the vessel and the maximum pressure it can stand for. In the present work it was observed that it is possible to allow venting during the digestion without losing volatile analytes, such as As, when properly controlling heating and chemical conditions. Recoveries for As in certified reference materials of animal tissues ranged from 94 to 112% despite mass losses as high as 62%mm−1 observed in the digests. However, for Hg(II) in medium containing chlorides recoveries were poor. The efficiency of digestion was measured by determination of organic carbon contents in digests and they ranged from 0.10 to 0.19% for plant and animal tissues. The temperature gradient along the vessel height is important for avoiding losses of volatile elements.

Headspace sorptive solid phase microextraction (HS-SPME) combined with a spectrophotometry system: A simple glass devise for extraction and simultaneous determination of cyanide and thiocyanate in environmental and biological samples

A simple, low cost and efficient headspace sorptive solid phase microextraction (HS-SPME) method for determination of cyanide has been developed. The system comprises of a glass tube with two valves and a moveable glass slide fixed at its centre. It includes an acceptor phase polyurethane foam treated mercury (II) dithizonate [Hg(HDz)2–PUF] complex fixed inside by a septum cap in a cylindrical configuration (5.0cm length and 1.0cm diameter). The extraction is based upon the contact of the acceptor phase to the headspace and subsequently measuring the absorbance of the recovered mercury (II) dithizonate from PUFs sorbent. Unlike other HSSE, extraction and back – extractions was carried out in a closed system, thereby improving the analytical performance by preventing the analyte loss. Under the optimized conditions, a linear calibration plot in the range of 1.0–50.0µmolL−1 was achieved with limits of detection (LOD) and quantification (LOQ) of 0.34, 1.2µmolL−1 CN−, respectively. Simultaneous analysis of cyanide and thiocyanate in saliva was also performed with satisfactory recoveries.

Simultaneous analysis of multiple classes of antimicrobials in environmental water samples using SPE coupled with UHPLC-ESI-MS/MS and isotope dilution

A robust and sensitive analytical method was developed for the simultaneous analysis of 21 target antimicrobials in different environmental water samples. Both single SPE and tandem SPE cartridge systems were investigated to simultaneously extract multiple classes of antimicrobials. Experimental results showed that good extraction efficiencies (84.5–105.6%) were observed for the vast majority of the target analytes when extraction was performed using the tandem SPE cartridge (SB+HR-X) system under an extraction pH of 3.0. HPLC-MS/MS parameters were optimized for simultaneous analysis of all the target analytes in a single injection. Quantification of target antimicrobials in water samples was accomplished using 15 isotopically labeled internal standards (ILISs), which allowed the efficient compensation of the losses of target analytes during sample preparation and correction of matrix effects during UHPLC-MS/MS as well as instrument fluctuations in MS/MS signal intensity. Method quantification limit (MQL) for most target analytes based on SPE was below 5ng/L for surface waters, 10ng/L for treated wastewater effluents, and 15ng/L for raw wastewater. The method was successfully applied to detect and quantify the occurrence of the target analytes in raw influent, treated effluent and surface water samples.

Sample Enrichment for Bioanalytical Assessment of Disinfected Drinking Water: Concentrating the Polar, the Volatiles, and the Unknowns.

Enrichment methods used in sample preparation for the bioanalytical assessment of disinfected drinking water result in the loss of volatile and hydrophilic disinfection byproducts (DBPs) and hence likely tend to underestimate biological effects. We developed and evaluated methods that are compatible with bioassays, for extracting nonvolatile and volatile DBPs from chlorinated and chloraminated drinking water to minimize the loss of analytes. For nonvolatile DBPs, solid-phase extraction (SPE) with TELOS ENV as solid phase performed superior compared to ten other sorbents. SPE yielded >70% recovery of nonpurgeable adsorbable organic halogens (AOX). For volatile DBPs, cryogenic vacuum distillation performed unsatisfactorily. Purge and cold-trap with crushed ice serving as condensation nuclei achieved recoveries of 50-100% for trihalomethanes and haloacetonitriles and approximately 60-90% for purged AOX from tap water. We compared the purgeable versus the nonpurgeable fraction by combining purge-and-trap extraction with SPE. The purgeable DBP fraction enriched with the purge-and-trap method exerted a lower oxidative stress response in mammalian cells than the nonpurgeable DBPs enriched with SPE after purging, while contributions of both fractions to bacterial cytotoxicity was more variable. 37 quantified DBPs explained almost the entire AOX in the purge-and-trap extracts, but <16% in the SPE extracts demonstrating that the nonpurgeable fraction is dominated by unknown DBPs.

Evaluation of sampling methods for sulfur speciation in volcanic gases

Determination of H2S and SO2 in fumarolic gases is necessary to predict volcanic activities. This study evaluated three gas sampling methods (CdS precipitation, Ag2S precipitation, and I2 oxidation) using artificial fumarolic gases with known compositions. H2S was initially fixed as CdS(s) or Ag2S(s) in the sulfide precipitations and S(0) in the I2 oxidation. On the other hand, SO2 was collected as dissolved species (SO32− and SO42−). The Ag2S precipitation, which did not allow HCl determination in fumarolic gases by forming AgCl(s), significantly underestimated H2S and SO2 due to the entrained loss of analytes as a result of water vaporization during H2O2 treatment. The I2 oxidation, which required duplicate sampling for complete analysis of H2S and SO2, tended to overestimate SO2 probably due to difficulties in separating S(0) particles from solutions. The CdS precipitation produced more satisfactory H2S and SO2 recoveries than the other methods. Additionally, the effect of delayed sample treatment was assessed by comparing H2S-to-SO2 molar ratios resulting from immediate and one-week-delayed treatments after gas collection. The delayed treatment significantly lowered the ratios in the CdS precipitation likely due to the susceptibility of CdS(s) to oxidation. In the meanwhile, such an effect was minimal in I2 oxidation. Similar results were also observed in the field evaluation of fumarolic gases at Mt. Hakone. Along with detailed sampling and treatment procedures, the causes for unsatisfactory H2S and SO2 recoveries were discussed in the context of the underlying reaction schemes as well as potential experimental artifacts. Thus, this study helps to select and further modify appropriate gas sampling methods to meet specific needs.

Improvements in the vapor-time profile analysis of explosive odorants using solid-phase microextraction

A modified approach for characterization of the vapor-time profile of the headspace odors of explosives was developed using solid-phase microextraction (SPME) incorporating introduction of an externally-sampled internal standard (ESIS) followed by gas chromatography/mass spectrometry (GC/MS) analysis. With this new method, reproducibility of the measurements of 2-ethyl-1-hexanol and cyclohexanone were improved compared to previous work (Hoffman et al., 2009; Arthur and Pawliszyn, 1990) through the use of stable-isotope-labeled internal standards. Exposing the SPME fiber to the ESIS after sampling the target analyte proved to be advantageous, while still correcting for fiber variability and detector drift. For the analysis of high volatility compounds, incorporation of the ESIS using the SPME fiber in the retracted position minimized the subsequent competitive loss of the target analyte, allowing for much longer sampling times.

Microextraction techniques in illicit drug testing: present and future.

Sample preparation is of utmost importance in both qualitative and quantitative analysis of illicit drugs because complex matrices, such as biological specimens, are involved in the assay. In forensic toxicology, the analysis is typically performed on biological fluids such as urine, serum and plasma. Matrices such as hair, oral fluid (OF), sweat, vitreous humor or meconium have become alternative options in recent times. Sample clean-up is a difficult step that takes 50–75% of the total analysis time and remains one of the main bottlenecks of modern illicit drug testing. Conventionally in forensic toxicology, sample preparation is conducted by liquid–liquid extraction (LLE), protein precipitation and solid-phase extraction (SPE). These techniques may involve large amounts of organic solvent and often require complex time-consuming multistep procedures, which can lead to low accuracy and precision, contamination and loss of analytes. For this reason, to address some of the shortcomings of current clean-up procedures, the development of new sample preparation techniques is attractive. Novel samplepreparation procedures are being increasingly used for illicit drug testing in biological matrices. Scaling down the conventional clean-up techniques is a recent trend in analytical chemistry and it allows the reduction of sample volume and organic solvent, leading to a cheaper, quicker and environment-friendly analysis. This editorial will therefore examine the most commonly used microextraction techniques and their potential in the determination of illicit drugs.

Simultaneous detection of xenon and krypton in equine plasma by gas chromatography-tandem mass spectrometry for doping control.

Xenon can activate the hypoxia-inducible factors (HIFs). As such, it has been allegedly used in human sports for increasing erythropoiesis. Krypton, another noble gas with reported narcosis effect, can also be expected to be a potential and less expensive erythropoiesis stimulating agent. This has raised concern about the misuse of noble gases as doping agents in equine sports. The aim of the present study is to establish a method for the simultaneous detection of xenon and krypton in equine plasma for the purpose of doping control. Xenon- or krypton-fortified equine plasma samples were prepared according to reported protocols. The target noble gases were simultaneously detected by gas chromatography-triple quadrupole mass spectrometry using headspace injection. Three xenon isotopes at m/z 129, 131, and 132, and four krypton isotopes at m/z 82, 83, 84, and 86 were targeted in selected reaction monitoring mode (with the precursor ions and product ions at identical mass settings), allowing unambiguous identification of the target analytes. Limits of detection for xenon and krypton were about 19 pmol/mL and 98 pmol/mL, respectively. Precision for both analytes was less than 15%. The method has good specificity as background analyte signals were not observed in negative equine plasma samples (n = 73). Loss of analytes under different storage temperatures has also been evaluated. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of Mercury in Istanbul Airborne Particles Using Solid Sampling High-Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry

ABSTRACTA method for the determination of mercury in airborne particles by solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry is reported. Fine urban airborne particles were collected every month on quartz filters using a high-volume sampler (500 L/min) in Istanbul, Turkey. The filters loaded with airborne particles were directly introduced into the graphite furnace so that analyte losses during digestion were eliminated. Moreover, to prevent analyte losses in the furnace, no pyrolysis step was taken and silver and gold nanoparticles were used as novel modifiers. The effects of graphite furnace program, pyrolysis and atomization temperature, and mass of sample introduced into the furnace were characterized. The limits of detection in the absence of any modifier, in the presence of silver nanoparticles, and in the presence of gold nanoparticles were 0.52, 0.38, and 0.19 µg/L, respectively. The mercury concentrations in the air particulates were between 0.74 ± 0.10 and 3.65 ± 0.33 µg/L.