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1.
Measurements in complex matrices like milk still present a challenge in biosensor development. This is especially important
when using a label-free detection method or when measuring low analyte concentrations. The direct optical method reflectometric
interference spectroscopy (RIfS) was used for investigating matrix effects in immunoassay development. Furthermore, approaches
to reduce these effects have been established. As a model system, the hormone testosterone has been chosen because this immunoassay
has been well characterized in buffer. In a first step, the immunoassay for the detection of testosterone in buffer was improved
beyond former published results. Therefore, the sensor surface was optimized, resulting in a fivefold lower limit of detection
(70.2 ng L−1) and limit of quantification (130.0 ng L−1). Additionally, the assay time could be reduced to 15 min. Consequently, we used this improved assay to investigate matrix
effects of whole pasteurized bovine milk. To minimize these effects, the surface chemistry was adapted and a suitable evaluation
method was established, reducing the effects of Tyndall scattering and nonspecific binding to the sensor surface. These improvements
allow for very reliable quantitative measurements in milk. The assay developed required no sample pretreatment and allowed
for the regeneration of the sensor surface so that calibration could be performed on one chip. The calibration in milk (3.5%
fat) resulted in a limit of detection of 94.4 ng L−1 and a limit of quantification of 229.3 ng L−1. Furthermore, recovery rates between 70% and 120% could be obtained. Thus, for the first time, an analyte in the matrix milk
was successfully quantified with RIfS at low concentrations. 相似文献
2.
The BioCD is a spinning-disc interferometric biosensor on which antibodies are immobilized to capture target antigens from
biological samples. In this work, BioCDs measured the interferometric response to prostate-specific antigen (PSA). The ideal
detection limit for PSA was determined using a BioCD with 12,500 printed target antibody spots with a corresponding number
of reference protein spots. Statistical analysis projects the detection limit of PSA as a function of the number of spots
included in the average. When approximately 10,000 spot pairs were averaged, the 3σ detection limit was 60 pg/ml in a 2 mg/ml simple protein background. A standard format for BioCD immunoassays uses 96 wells
with 32 target spots paired with reference spots. In serum, the detection limit for this format was 1 ng/ml in 3:1 diluted
female human serum using a sandwich assay with a nonfluorescent mass tag. 相似文献
3.
A polymer optical backplane capable of generic luminescence detection within microfluidic chips is demonstrated using large core polymer waveguides and vertical couplers. The waveguides are fabricated through a new process combining mechanical machining and vapor polishing with elastomer microtransfer molding. A backplane approach enables general optical integration with planar array microfluidics since optical backplanes can be independently designed but still integrated with planar fluidic circuits. Fabricated large core waveguides exhibit a loss of 0.1 dB cm(-1) at 626 nm, a measured numerical aperture of 0.50, and a collection efficiency of 2.86% in an n = 1.459 medium, comparable to a 0.50 NA microscope objective. In addition to vertical couplers for out-of-plane collection and excitation, polymer waveguides are doped with organic dyes to provide wavelength selective filtering within waveguides, further improving optical device integration. With large core low loss waveguides, luminescence collection is improved and measurements can be performed with simple LEDs and photodetectors. Fluorescein detection via fluorescence intensity with a limit of detection (3sigma) of 200 nM in a 1 microL volume is demonstrated. Phosphorescence lifetime based oxygen detection in water in an oxygen controllable microbial cell culture chip with a limit of detection (3sigma) of 0.08% or 35 ppb is also demonstrated utilizing the waveguide backplane. Single waveguide luminescence collection performance is equivalent to a back collection geometry fiber bundle consisting of nine 500 microm diameter collection fibers. 相似文献
4.
Jing-Wei Sun Bing Liu Yan Zhang Shuo Wang 《Analytical and bioanalytical chemistry》2009,394(8):2223-2230
The development of a direct competitive enzyme-linked immunosorbent assay based on polyclonal antibodies for N-methylcarbamate insecticide metolcarb is described. Two new haptens for the metolcarb were designed and synthesized. Both
haptens were conjugated with keyhole limpet hemocyanin to form the immunogens. Four rabbits were immunized with the immunogens
for production of polyclonal antibodies against metolcarb. Antisera titers were tested on the homologous coating antigens
using a noncompetitive indirect enzyme-linked immunosorbent assay. The high titer antisera were used to develop the direct
competitive enzyme-linked immunosorbent assay for the detection of metolcarb. The antibody–antigen combination with the highest
selectivity for metolcarb was further optimized and its tolerance to changes in chemical conditions (ionic strength, pH value,
and organic solvent) was studied. Under optimum conditions, the sensitivity and the limit of detection were determined to
be 22 μg L−1 and 1.2 μg L−1 respectively. Determination of metolcarb in fruit juices and vegetables was accomplished by simple, rapid, and efficient
extraction methods. Recoveries of metolcarb from spiked samples ranged from 80.5% to 109.5%. Validation of the developed immunosorbent
assay was conducted by comparison of results from high-performance liquid chromatography. The correlation between the data
obtained using developed immunosorbent assay and high-performance liquid chromatography was high (R
2 = 0.9884). Therefore, the developed immunosorbent assay in this study was suitable for the rapid quantitative determination
of metolcarb in agricultural products. 相似文献
5.
Herein, we report a polyaniline-nickel oxide (PANI-NiO) nanocomposite as an efficient immobilization matrix for development the optical fiber urea biosensor. Optical fiber sensing probe was developed by removing some portion of optical fiber at middle and modified with PANI-NiO matrix. After the modification of cladding removed portion, it was immobilized with enzyme urease via glutaraldehyde as a bi-functional cross-linking agent. The physicochemical and optical properties of the PANI-NiO matrix were explored by X-ray diffraction, scanning electron microscopy, ultraviolet–visible, and Fourier transform infrared spectroscopic techniques. The characteristic features and performance of the developed sensor were evaluated via recording the output power and modal power distribution by means of a charge-coupled device camera. The developed urea biosensor exhibits a selective response towards urea concentrations in the linear range 1 nM–100 mM with a lower detection limit of 1 nM. Sensor recorded as a 40 days stability and response time ~1 min. Thus, the obtained experimental results of the developed sensor promote its applicability with practical prospects in diverse field. 相似文献
6.
F. Baldini L. Bolzoni A. Giannetti M. Kess P. M. Krämer E. Kremmer G. Porro F. Senesi C. Trono 《Analytical and bioanalytical chemistry》2009,393(4):1183-1190
A new immunosensor for the determination of procalcitonin was developed. A sandwich assay format was implemented on a polymethylmetacrylate
optical biochip, opportunely shaped in order to obtain several flow channels and potentially suitable for point of care testing
applications. The sandwich format makes use of two new rat monoclonal antibodies. The capture antibody was covalently immobilised
on the surface of the plastic chip, and the detection antibody was labelled with DY647 dye. Different combinations of capture
and detection antibodies were investigated, and particular attention was devoted in order to avoid the non-specific adsorption.
A limit of detection of 0.088 mg L−1 was achieved within the working range of 0.28–50 mg L−1 in buffer samples. The assay was also implemented in human serum, and 0.2 and 0.7–25 mg L−1 were the attained limit of detection and working range, respectively. 相似文献
7.
The combination of spin-coating and rapid thermal annealing is a very important sol–gel technique to prepare high quality
silicate glass films, widely used in the fabrication of waveguides, photonic bandgap structures and other film-based optical
devices. This work found that high rare-earth concentrations will seriously affect the optical quality of the films prepared
by the spin-coating/rapid thermal annealing process, with pores with hundreds of nanometres in size being found in heavily
rare-earth doped aluminosilicate glass films, causing significant light scattering. However, it was also found that a new
recipe using acetylacetone was able to dramatically eliminate these pores and to improve the film optical quality, even for
rare-earth concentrations as high as 15 mol%. This result will be useful for the fabrication of sol–gel derived devices based
on rare-earth doped silicate glass films like active waveguides, functional films and photonic bandgap structures. 相似文献
8.
A rapid and sensitive method was developed here for separation and detection of multiple pathogens in food matrix by magnetic
surface-enhanced Raman scattering (SERS) nanoprobes. Silica-coated magnetic probes (MNPs@SiO2) of ∼100 nm in diameter were first prepared via the reverse microemulsion method using cetyltrimethylammonium bromide as
a surfactant and tetraethyl orthosilicate as the silica precursor. The as-prepared MNPs@SiO2 were functionalized with specific pathogen antibodies to first capture threat agents directly from a food matrix followed
by detection using an optical approach enabled by SERS. In this scheme, pathogens were first immuno-magnetically captured
with MNPs@SiO2, and pathogen-specific SERS probes (gold nanoparticles integrated with a Raman reporter) were functionalized with corresponding
antibodies to allow the formation of a sandwich assay to complete the sensor module for the detection of multiple pathogens
in selected food matrices, just changing the kinds of Raman reporters on SERS probes. Here, up to two key pathogens, Salmonella enterica serovar Typhimurium and Staphylococcus aureus, were selected as a model to illustrate the probability of this scheme for multiple pathogens detection. The lowest cell
concentration detected in spinach solution was 103 CFU/mL. A blind test conducted in peanut butter validated the limit of detection as 103 CFU/mL with high specificity, demonstrating the potential of this approach in complex matrices. 相似文献
9.
M. D. Lechner Helmut Cölfen Vikas Mittal Antje Völkel Wendel Wohlleben 《Colloid and polymer science》2011,289(10):1145-1155
Analytical ultracentrifugation is one of the most powerful methods for the characterization of nanoparticles since the days
of its invention due to its high resolution and statistical significance. Latexes with different sizes and their mixtures
have been measured by sedimentation with the analytical ultracentrifuge (AUC) OPTIMA XL-I (Beckman Coulter, Palo Alto, CA,
USA) with interference optics at λ
0 = 675 nm and absorption optics at λ
0 = 546 and 263 nm. Additionally, a blue pigment with high absorption characteristic at visible light has been investigated.
A large influence of Mie scattering and Mie absorption on the particle size distribution with respect to absorption optics
and samples with moderate or broad size distribution is observed. Therefore, the consideration of the Mie scattering effect
is compulsory for most AUC measurements of nanoparticles with absorption optics. 相似文献
10.
Bernini R De Nuccio E Brescia F Minardo A Zeni L Sarro PM Palumbo R Scarfi MR 《Analytical and bioanalytical chemistry》2006,386(5):1267-1272
This paper describes an innovative integrated micro flow cytometer that presents a new arrangement for the excitation/detection
system. The sample liquid, containing the fluorescent marked particles/cells under analysis, is hydrodynamically squeezed
into a narrow stream by two sheath flows so that the particles/cells flow individually through a detection region. The detection
of the particles/cells emitted fluorescence is carried out by using a collection fiber placed orthogonally to the flow. The
device is based on silicon hollow core antiresonant reflecting optical waveguides (ARROWs). ARROW geometry allows one to use
the same channel to guide both the sample stream and the fluorescence excitation light, leading to a simplification of the
optical configuration and to an increase of the signal-to-noise ratio. The integrated micro flow cytometer has been characterized
by using biological samples marked with standard fluorochromes. The experimental investigation confirms the success of the
proposed microdevice in the detection of cells.
An erratum to this article can be found at 相似文献
11.
Small-volume fiber-optic evanescent-wave absorption sensor for nitrite determination 总被引:1,自引:0,他引:1
Yan Xiong Dao-qian Zhu Chun-feng Duan Jian-wei Wang Ya-feng Guan 《Analytical and bioanalytical chemistry》2010,396(2):943-948
A novel small-volume fiber-optic evanescent-wave absorption sensor based on the Griess–Ilosvay reaction has been developed
and evaluated for nitrite determination. The sensor was constructed by inserting a decladded optical fiber into a transparent
capillary to form an annular column microchannel. The Evanescent wave (EW) field produced on the optical fiber core surface
penetrated into the surrounding medium and interacted with the azo dye, which was generated by the reaction of nitrite and
nitrite-sensitive reagents. The detector was designed to be parallel to the axis of the optical fiber. The defined absorbance
was linear with the concentration of nitrite in the range from 0.05 to 10 mg L−1, and the detection limit was 0.02 mg L−1 (3σ) with the relative standard deviation (RSD) of 2.6% (n = 8). The present sensor was successfully used to determine nitrite in real samples of mineral water, tap water, rain water,
and seawater. The results were consistent with the data obtained by standard spectrophotometric method, showing potential
of the proposed sensor for practical application.
相似文献
12.
Robert Nooney Andrew Clifford Xavier LeGuevel Ondrej Stranik Colette McDonagh Brian D. MacCraith 《Analytical and bioanalytical chemistry》2010,396(3):1127-1134
In this work, we used a model assay system (polyclonal human IgG–goat antihuman IgG) to elucidate some of the key factors
that influence the analytical performance of bioassays that employ metal-enhanced fluorescence (MEF) using silver nanoparticles
(NPs). Cy5 dye was used as the fluorescent label, and results were compared with a standard assay performed in the absence
of NPs. Two sizes of silver NPs were prepared with respective diameters of 60 ± 10 and 149 ± 16 nm. The absorption spectra
of the NPs in solution were fitted accurately using Mie theory, and the dipole resonance of the 149-nm NPs in solution was
found to match well with the absorption spectrum of Cy5. Such spectral matching is a key factor in optimizing MEF. NPs were
deposited uniformly and reproducibly on polyelectrolyte-coated polystyrene substrates. Compared to the standard assay performed
without the aid of NPs, significant improvements in sensitivity and in limit of detection (LOD) were obtained for the assay
with the 149-nm NPs. An important observation was that the relative enhancement of fluorescence increased as the concentration
of antigen increased. The metal-assisted assay data were analyzed using standard statistical methods and yielded a LOD of
0.086 ng/mL for the spectrally matched NPs compared to a value of 5.67 ng/mL obtained for the same assay in the absence of
NPs. This improvement of ∼66× in LOD demonstrates the potential of metal-enhanced fluorescence for improving the analytical
performance of bioassays when care is taken to optimize the key determining parameters.
相似文献
13.
A microfluidic device with integrated fluorimetric detection for flow injection analysis 总被引:1,自引:0,他引:1
Alexandre Fonseca Ivo M. Raimundo Jr. Jarbas J. R. Rohwedder Renato S. Lima Mário C. Ugulino Araújo 《Analytical and bioanalytical chemistry》2010,396(2):715-723
This work describes the development of flow analysis microsystems with integrated fluorimetric detection cells. Channels (width
of 300–540 μm and depth of 200–590 μm) were manufactured by deep-UV lithography in urethane–acrylate (UA) resin. Plastic optical
fibers (diameter of 250 μm) were coupled to a 2.0-mm-long detection channel in order to guide the excitation radiation from
an LED (470 nm) and collect the emitted radiation at a right angle towards a photomultiplier. A single-line miniaturized system,
with a total internal volume of 10.4 μL, was evaluated by means of standard fluorescein solutions (0.53–2.66 μmol L−1, pH 8.5). The analytical signals presented a linear relationship in the concentration range studied, with a relative standard
deviation of 1.9% (n = 5), providing a detection limit of 0.37 μmol L−1 and an analytical frequency of 60 samples/h, using a flow rate of 60 μL min−1. Optical microscopy images and videos acquired in real time for the hydrodynamic injection of 130 and 320 nL of sample solutions
indicated the good performance of the proposed sampling strategy. Another microsystem with a total internal volume of 38 μL
was developed, incorporating a confluence point for two solutions. This device was applied to the determination of the total
concentration of Ca2+ and Mg2+ in commercial mineral waters using the calcein method. Microscopy images and videos demonstrated the mixing efficiency of
the solutions in the microchannels. A linear relationship was observed for the analytical signal in the Ca2+ concentration range from 25 to 125 μmol L−1, with relative standard deviations of 3.5%. The analysis of mineral waters with the proposed system provided results that
did not differ significantly from those obtained by the EDTA titration method at a confidence level of 95%. These results
demonstrate the viability of developing micro flow injection systems with an integrated fluorimetric detection cell.
相似文献
14.
Francesca Speroni Lisa Elviri Maria Careri Alessandro Mangia 《Analytical and bioanalytical chemistry》2010,397(7):3035-3042
An innovative enzyme-linked immunosorbent assay (ELISA) format based on antibody-coated magnetic micro-particles (MPs) for
the sensitive detection of Ara h3/4 allergen in food is described. The immunosupport is suspended in the incubation solutions
and the MPs with the captured allergen can be easily harvested on a magnet, separated from the solutions, and washed using
an easy-to-use, fast and selective approach that allows its detection and quantification. Two differently coated MPs, ProteinA-Pn-b
and MP-NH2-PAMAM G 1.5 -Pn-b immunosupports, were tested. The functionalization of the MPs with PAMAM-sodium carboxylate dendrimers
elicits a major stability on the immunoglobulin activity resulting in a threefold enhancement of the analytical sensitivity
for the assay with respect to a ProteinA immobilization. Validation was carried out on two different matrices: corn flakes
and biscuits. In the case of MP-NH2-PAMAM G 1.5 -Pn-b immunosupport, limit of detection was found to be 0.2 mg peanuts/kg matrix in both matrices; the linear
response range was demonstrated from 2.5 to 15 mg peanuts/kg matrix by performing statistical tests (homoscedasticity and
Mandel fitting tests). Good accuracy and recovery (>80 ± 2%) were obtained. Different food samples were tested and the results
were compared with those obtained with a commercially available ELISA kit. The results obtained in this work demonstrated
the applicability of the immunomagnetic ELISA methods on real samples and the possibility to perform the assay with significantly
reduced reagent and sample consumption. 相似文献
15.
The detection and confirmation of cannabinoids in oral fluid are important in forensic toxicology. Currently, the presence
of Δ9-tetrahydrocannabinol (THC) is used for the detection of cannabis in oral fluid. A low concentration of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) is found in oral fluid, which suggested a convenient and low-sensitivity confirmation assay
can be used in a routine forensic laboratory. In this study, a highly sensitive isotope dilution liquid chromatography–tandem
mass spectrometry method following dansylation was successfully developed for simultaneous determination of THC and THC-COOH
in oral fluid. The dansylated derivatives dramatically demonstrated and enhanced the sensitivity of THC and THC-COOH. To avoid
signal influenced by the matrix, a 5-min liquid chromatography gradient program was evaluated and optimized, which reduced
the sample diffusion and caused sharp peaks (less than 12 s) and thus helped to achieve detection at a low level. The sensitivity,
accuracy, and precision were also evaluated, and high quantitative accuracy and precision were obtained. The limit of quantitation
of this approach was 25 pg/mL for THC and 10 pg/mL for THC-COOH in oral fluid. Finally, the method was successfully applied
to eight suspected cannabis users. Among them, in six oral fluid samples THC-COOH was determined at a concentration from 13.1
to 47.2 pg/mL. 相似文献
16.
Raghuraj Singh Chouhan Aaydha Chidambara Vinayaka Munna Singh Thakur 《Analytical and bioanalytical chemistry》2010,397(4):1467-1475
Quantum dots (QDs) are preferred as high-resolution biological fluorescent probes because of their inherent optical properties
compared with organic dyes. This intrinsic property of QDs has been made use of for sensitive detection of methylparathion
(MP) at picogramme levels. The specificity of the assay was attributed to highly specific immunological reactions. Competitive
binding between free MP and CdTe QD bioconjugated MP (MP-BSA-CdTe) with immobilized anti-MP IgY antibodies was monitored in
a flow-injection system. The fluorescence intensity of MP-BSA-CdTe bioconjugate eluted from the column was found to be directly
proportional to the free MP concentration. Hence, it was possible to detect MP in a linear range of 0.1–1 ng mL−1 with a regression coefficient R
2 = 0.9905. In this investigation, IgY proved advantageous over IgG class immunoglobulins in terms of yield, stability, cost
effectiveness, and enhancement of assay sensitivity. The photo-absorption spectrum of bioconjugated CdTe QD (λ
max = 310 nm) confirmed nano-biomolecular interactions. The results suggest the potential application of bioconjugation and nano-biomolecular
interactions of QDs for biological labeling and target analyte detection with high sensitivity. 相似文献
17.
Esposito S Deventer K T'Sjoen G Vantilborgh A Delbeke FT Goessaert AS Everaert K Van Eenoo P 《Analytical and bioanalytical chemistry》2012,402(9):2789-2796
This work describes a liquid chromatography–electrospray tandem mass spectrometry method for detection of desmopressin in
human plasma in the low femtomolar range. Desmopressin is a synthetic analogue of the antidiuretic hormone arginine vasopressin
and it might be used by athletes as a masking agent in the framework of blood passport controls. Therefore, it was recently
added by the World Anti-Doping Agency to the list of prohibited substances in sport as a masking agent. Mass spectrometry
characterization of desmopressin was performed with a high-resolution Orbitrap-based mass spectrometer. Detection of the peptide
in the biological matrix was achieved using a triple-quadrupole instrument with an electrospray ionization interface after
protein precipitation, weak cation solid-phase extraction and high performance liquid chromatography separation with an octadecyl
reverse-phase column. Identification of desmopressin was performed using three product ions, m/z 328.0, m/z 120.0, and m/z 214.0, from the parent ion, m/z 535.5. The extraction efficiency of the method at the limit of detection was estimated as 40% (n = 10), the ion suppression as 5% (n = 10), and the limit of detection was 50 pg/ml (signal-to-noise ratio greater than 3). The selectivity of the method was
verified against several endogenous and synthetic desmopressin-related peptides. The performance and the applicability of
the method were tested by analysis of clinical samples after administration of desmopressin via intravenous, oral, and intranasal
routes. Only after intravenous administration could desmopressin be successfully detected. 相似文献
18.
Brian C. Mackness Melisenda J. McDonald 《Analytical and bioanalytical chemistry》2010,397(7):3151-3154
Prostate-specific antigen (PSA) is a serum glycoprotein overproduced by the prostate in prostate cancer (≥4 ng/mL in the bloodstream).
An immunoassay for total PSA (tPSA) was developed using the ALYGNSA method to enhance capture antibody orientation and a limit of detection of 0.63 ng/mL
was reported, a limit 15-fold lower than a commercial tPSA ELISA assay. This ALYGNSA assay, however, was performed using only buffer-based proteins and blocking agents (Mackness
et al., Anal Bioanal Chem 396:681–686, 2010). To improve the clinical application of this system, a serum-based tPSA ALYGNSA was developed employing human serum. This assay also resulted in a limit of detection of 0.63 ng/mL of tPSA protein. The findings reported here provide support for the clinical application of this assay for diagnosis, progression,
treatment, and possible recurrence of prostate cancer. 相似文献
19.
Abel L. Thangawng Jason S. Kim Joel P. Golden George P. Anderson Kelly L. Robertson Vyechi Low Frances S. Ligler 《Analytical and bioanalytical chemistry》2010,398(5):1871-1881
With a view toward developing a rugged microflow cytometer, a sheath flow system was micromachined in hard plastic (polymethylmethacrylate)
for analysis of particles and cells using optical detection. Six optical fibers were incorporated into the interrogation region
of the chip, in which hydrodynamic focusing narrowed the core stream to ∼35 μm × 40 μm. The use of a relatively large channel
at the inlet as well as in the interrogation region (375 μm × 125 μm) successfully minimized the risk of clogging. The device
could withstand pressures greater than 100 psi without leaking. Assays using both coded microparticles and cells were demonstrated
using the microflow cytometer. Multiplexed immunoassays detected nine different bacteria and toxins using a single mixture
of coded microspheres. A549 cancer cells processed with locked nucleic acid probes were evaluated using fluorescence in situ
hybridization. 相似文献
20.
Redondo R Machado VC Baeza M Lafuente J Gabriel D 《Analytical and bioanalytical chemistry》2008,391(3):789-798
Biogas is produced by biological processes under anaerobic conditions and may contain up to 20,000 ppmv hydrogen sulfide (H2S), a corrosive substance that attacks power engines and can affect the health of the industrial staff. H2S must be removed from the biogas, especially in co-generation facilities where the biogas is burnt for energy production.
Nowadays, biofiltration is being studied and considered as an interesting alternative for removing H2S from the biogas besides classical chemical processes. The novelty of this work is the design and construction of an automated
H2S on-line analyser to assess the composition of the liquid and gas phases of gas-phase bioreactors. The analyser is made of
two parallel flow configurations which share the same detection device. The first configuration is a single-channel flow injection
analyser (FIA) to detect S2− in the liquid phase. The second configuration is a continuous flow analyser (CFA) with a gaseous diffusion step (GD–CFA)
for detecting H2S in the gas phase. The diffusion step enables separation of the H2S(g) from the sample and its conversion into a detectable chemical species (S2−). S2− detection was performed with an Ag2S ion-selective electrode (ISE) selective to . The main response parameters of the FIA system are a linear range between 3 × 10−5 and 1 × 10−1 mol L−1 S2− (0.61–3,200 mg L−1), with a sensitivity of 27.9 mV decade−1 and a detection limit of 1.93 × 10−5 mol L−1 S2−. The GD–CFA configuration presents a linear range between 400 and 10,000 ppmv H2S(g) with a sensitivity of 26.1 mV decade−1 and a detection limit of 245 ppmv H2S. The proposed analyser was used by analysing real gas and liquid samples with optimal results at a full-scale biotrickling
filter for biogas treatment at a municipal wastewater treatment plant.
Figure The novelty of this work is the design and construction of an automated H2S on-line analyzer to assess the composition of the liquid and gas phases of gas-phase bioreactors. The analyser is made of
two parallel flow configurations which share the same detection device. The first configuration is a single-channel flow injection
analyser (FIA) to detect S2- in the liquid phase. The second configuration is a continuous flow analyser (CFA) with a gaseous diffusion step (GD-CFA)
for detecting H2S in the gas phase. 相似文献