NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 30
·12962-12966
·
IF 3.288
Jing Sun,Rui Wang,Meng Xia,Shuyun Zhu,Xian-En Zhao
As alternatives to nanozymes, some metal ions have been used in chemical/biochemical sensors owing to their facile acquisition avoiding tedious preparation and purification. Ce4+ has been reported to possess oxidase-like activity. Ascribed to its strong oxidative ability, Ce4+ can trigger the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to its blue product oxTMB without the requirement of H2O2. When ALDS is added, the oxidation ability of Ce4+ can be reduced because of the redox reaction between Ce4+ and ALDS. The absorbance intensity ascribed to oxTMB decreases followed by the fading of the solution. On the basis of such a mechanism, a simple method is proposed for monitoring ALDS in two linear ranges of 0.1–10.0 μM and 10.0–60.0 μM. The detection limit is low to 0.05 μM. Furthermore, this method exhibits great potential for ALDS detection in real biological body fluids and pharmaceutical samples.
研究领域:
分析化学
·
药物分析
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DOI
高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
·
2014
·Vol. 238
·期 5
·889-894
·
IF 1.387
Zhu Jinghui,Li Chunyan,Liu Shaopu,Liu Zhongfang,Yang Jidong,Tian Jing,Hu Xiaoli
A non-diazotization-coupling reaction-based colorimetric method was developed and validated for the determination of nitrite in tap water and milk samples. Under acidic condition, nitrite could selectively react with pyrrole, resulting in the emerging of a new absorption peak at 509 nm and a distinct color change from clear to red, with which the concentration of nitrite can be determined indirectly. Excellent linear range was achieved from 0.72 to 40.0 μmol L −1 with a detection limit of 0.22 μmol L −1 . The detection limit was lower than or comparable to most of the recently published methods. The experimental conditions were optimized, and effects of coexisting substances were evaluated, and the results showed excellent priority since a certain amount of other anions, including SO 3
− , SeO 3
− and other acid radicals, would not interfere with the measurement. We highlighted the simplicity and efficiency of this method as no diazotization-coupling procedure and toxic aniline were involved. Determination of nitrite in tap water and milk samples was performed.
研究领域:
分析化学
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环境科学
·
食品科学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Miaomiao Song,Weihua Ma
Increasing attention has been directed towards oxidase mimics due to their catalytic ability toward enzyme substrates in the absence of H 2 O 2 , offering great colorimetric sensing potential in assays and diagnostics. However, slow electron-transfer and unstable absorbance over time often lead to unsatisfactory enzymatic reaction rates and unreliable readouts, significantly reducing detection efficiency and accuracy. Herein, we report on an Ag 6 Si 2 O 7 nanozyme utilizing 3,3′,5,5′-tetramethylbenzidine (TMB) as a chromogenic substrate, demonstrating excellent oxidase-like activity and long-term stable colorimetric signals. Experimental results reveal that the excellent catalytic kinetics of Ag 6 Si 2 O 7 (K m = 0.197 mM, Vmax = 5.1 × 10 −7 M/s) are attributed to ultrafast electron transfer between Ag + and TMB, mediated by Ag 2 O intermediates formed from self-released alkaline ions. Additionally, self-released H 2 SiO 4 2− improves the stability of the oxidized substrate, resulting in a long-term stable colorimetric signal (∼20 min), which exhibits reliable accuracy regardless of the time point at which analyte is added within 20 min, thus eliminating the interference of individual operation time errors. Ascorbic acid (AA) is selected as the target molecule to assess the performance of the Ag 6 Si 2 O 7 -TMB colorimetric sensing system. This approach demonstrates a wide detection range from 5 to 300 μM and a detection limit of 0.452 μM. The developed colorimetric sensing strategy exhibits good stability, specificity, rapidity, and potential application in real sample detection.
研究领域:
生物化学
·
分析化学
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医学诊断
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DOI
高影响因子
TALANTA
·
2015
·
IF 3.545
Yumin Leng,Kun Xie,Liqun Ye,Genquan Li,Zhiwen Lu,Junbao He
A highly selective method is presented for the colorimetric determination of dopamine (DA) using gold nanoparticles (AuNPs). DA caps on the surface of AuNPs (DA-AuNPs) induces the aggregation of AuNPs in alkaline solution. The DA-AuNPs are modified by the hydrolysate of thioglycolic acid (TGA 2 − ) through Au–S bonds. The aggregation of AuNPs is accelerated by TGA 2− , due to the strong hydrogen-bonds (NH⋯OC and OH⋯OC) formed between TGA 2 − and DA. Upon the addition of DA, the solution shows a color change from red to purple (or yellow), which is also monitored to detect DA in human urine and fetal bovine serum samples. Here, the limits of colorimetric detection are as low as 10 −7 M observed in Milli-Q water, urine and serum. Based on UV–vis absorption spectra, the limits of detection have been calculated to be 3.3×10 −8 M, 1.0×10 −7 M and 9.4×10 −8 M in Milli-Q water, urine, and serum, respectively. All the limits of detection are lower than the lowest abnormal concentrations of DA in urine (5.7×10 −7 M) and blood (1.6×10 −5 M). The good linear ranges from 0 to 10 −6 M are used for the quantitative assay of DA in urine and serum samples. The applicability of our detection system is also verified by analysis of DA in urine and serum samples. The developed approach is without using complex financial instruments.
研究领域:
分析化学
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医学检验
·
纳米生物学
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DOI
PubMed
高影响因子
ANALYTICAL SCIENCES
·
2020
·Vol. 37
·期 2
·267-274
·
IF 2.049
Ghoto Saima Ameen,Khuhawar Muhammad Yar
A convenient and uncomplicated scheme has been projected for the quantitative determination of essential diamines putrescine (PUT) and cadaverine (CAD) via sodium dodecyl sulfate protected silver nanoparticles (SDS-AgNPs). This scheme is based on the chemical interaction of a SDS-AgNPs probe with PUT and CAD, leading to a color change from yellow to red or reddish brown. The interaction was investigated through different techniques such as using a UV-visible spectrophotometer, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), dynamic light scattering spectroscopy (DLS) and the zeta potential. Both amines possess a close resemblance in structure (except for the addition of one more methylene group in CAD), and no any distinguishable color change was noted. However, the maximum absorption band at 580 and 600 nm was demonstrated for PUT and CAD correspondingly. The methodical response was observed at absorption ratios of 580/410 and 600/410 nm, with the linear regression within 4–12 and 6–14 μg/mL for PUT and CAD. The detection limits calculated for both the diamines PUT and CAD were 0.333 and 1.638 μg/mL. The scheme was successfully applied for determinations in biological samples, including spiked blood plasma and urine. Putrescine exhibited % recovery within 95.717–105.200%, while cadaverine was within 95.940–105.109%, respectively. The scheme was reproducible and precise with inter-day RSD ( n = 5) within 1.126, 0.018% and the intraday RSD ( n = 5) was within 0.005, 0.002% for PUT and CAD, respectively.
研究领域:
分析化学
·
生物医学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2022
·Vol. 14
·期 18
·1803-1809
·
IF 3.532
Dingmin Liu,Pengcheng Huang,Fang-Ying Wu
A colorimetric assay was described for determination of tetracyclines (TCs) in complex matrices based on dual regulation of gold nanoparticle (AuNP) aggregation and in situ silver metallization. The reaction between p-aminophenol and silver ions (Ag+) catalyzed by aptamer (Apt)-functionalized AuNPs promoted the in situ deposition of Ag shells on AuNPs to afford core–shell bimetallic NPs (Au@AgNPs). When the target is present, Apt is separated from the AuNP surface through the Apt-target interaction. With the desorption of Apts, AuNPs catalyzed the formation of more aggregated Au@AgNPs with a thinner Ag shell, corresponding to the solution color gradually changing from orange-yellow to brown. Using A600/A410 as the determination signal, the assay gave visible linear relationships for TCs in the range of 0.3–6.0 μmol L−1 with a detection limit (LOD) of 33.6 nmol L−1. In particular, the assay was successfully applied to detect TCs in real samples with the recovery rate ranging from 91.2% to 106% and relative standard deviation (RSD) less than 4.6%. These results meet the requirements of sample analysis.
研究领域:
分析化学
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纳米生物学
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DOI
PubMed
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 23
·4123
·
IF 5.719
Li Zhang,Linhong Ge,Lamei Deng,Xinman Tu
Herein, CuS was incorporated with ZnS to form a novel nanocomposite via cation exchange, and the product was then employed for dual application of the colorimetric determination and photocatalytic degradation of tetracycline (TC) in water. The formed p–n heterojunction provided an improved gap width and electron mobility, which could rapidly catalyze H2O2to produce plenty of •OH, supporting a color conversion with TMB. Meanwhile, the addition of TC could lead to the further enhancement in colorimetric signal, and the distinction level was sensitive to the target amount. Additionally, under light conditions, the p-CuS/n-ZnS could produce •O2−, •OH, and h+through photocatalysis, and these ions could degrade the TC via oxidation. In the colorimetric determination of TC, the signal responses were obtained within 10 min, and the detection limit was 20.94 nM. The recovery rates were 99% and 106% for the water samples from Ganjiang river. In the photocatalytic degradation, the TC was degraded by 91% within 120 min, which was threefold that of ZnS. Meanwhile, the morphology feature of the p-CuS/n-ZnS remained after multiple uses, suggesting a favorable material stability. This strategy provides application prospects for the monitoring and control of antibiotics in water.Keywords:p–n heterojunction;tetracycline;colorimetric determination;photocatalysis;degradation
研究领域:
环境科学
·
材料科学
·
分析化学
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2018
·
IF 2.746
Shixu Huang,Yongna Jin,Guoming Cao,Yunfei Tian,Kailai Xu,Xiandeng Hou
A highly selective, sensitive yet simple colorimetric assay was developed for Se(IV) detection based on the silver nanoparticles (AgNPs), with hydride generation for separation and sample introduction. The proposed method could be easily performed by introducing the hydride vapor of the analyte (H 2 Se) into a thioglycolic acid (TGA) capped AgNPs solution. A combination of experimental and theoretical studies was used to illustrate the mechanism of this AgNPs colorimetric assay. The strong interaction of AgNPs with Se 0 (oxidation product of H 2 Se) and/or H 2 Se weakens the stabilizing effect of TGA on AgNPs, leading to the aggregation of AgNPs and thus the color change of the AgNPs solution from bright yellow to light yellow or even colorless with the increase of Se(IV) concentration. The limit of detection was found to be 5 μg L −1 with UV–vis spectrophotometric detection, and 50 μg L −1 with the naked eye visual observation. The proposed method showed excellent selectivity and was successfully applied for Se(IV) determination in fish protein and sea water samples.
研究领域:
分析化学
·
环境科学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 4
·1185-1190
·
IF 4.58
Gong Lingling,Du Bibai,Pan Long,Liu Qingju,Yang Kunhao,Wang Wei,Zhao Hong,Wu Li,He Yujian
The authors describe a colorimetric assay for the determination of As(III) in aqueous solution using citrate capped gold nanoparticles (AuNPs) which, in the presence of As(III), undergo aggregation due to the interaction of citrate ion with As(III). This results in an easily detectable color change from wine-red to blue. The ratio of the absorbances at 661 and 519 nm is linearly related to the As(III) concentration in the 4 to 100 ppb range, with a detection limit as low as 1.8 ppb (at 3σ) which is below the guideline value of 10 ppb. The method is rather simple in that it does not require the surface of the AuNPs to be modified. It was successfully applied to the determination of As(III) in spiked drinking water where it gave adequate recoveries.
The ratio of the absorbances at 661 and 519 nm is linearly related to the As(III) concentration in the 4 to 100 ppb range, with a detection limit as low as 1.8 ppb (at 3σ) which is below the guideline value of 10 ppb.
研究领域:
分析化学
·
环境科学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2016
·Vol. 183
·期 6
·1865-1872
·
IF 4.831
Huang Pengcheng,Li Jianfang,Song Juan,Gao Nan,Wu Fangying
The authors demonstrate a single-step histidine assay that is based on the use of silver nanoparticles modified with sulfanilic acid (SAA-AgNPs). The presence of histidine leads to a visually detectable gradual color change from bright yellow via orange to purple. The effect is assumed to be mainly due to strong π-π stacking, electrostatic interaction, and hydrogen bonding between SAA and histidine. The assay has a 52.7 nM detection limit and works in the 0 to 3.5 μM concentration range. It is selective over other compounds when using appropriate masking agents. The method has been successfully applied to the colorimetric determination of histidine in (spiked) serum samples. Recoveries ranged between 97 % and 107 %, and relative standard deviations are <0.92 % (for n = 3). The method was also applied to detect polyhistidine-tagged cysteine (His-His-His-His-His-His-Cys) which can be quantified in concentrations down to 5.57 nM. This finding links the method to His-tag technology.
A single-step colorimetric assay for histidine is developed using sulfanilic acid modified silver nanoparticles (SAA-AgNPs) via π stacking, electrostatic interaction, and hydrogen bonding resulting in the aggregation of the AgNPs and a color change from yellow to orange.
研究领域:
分析化学
·
生物化学
·
医学诊断
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DOI
高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 3
·1-8
·
IF 5.705
Zong Chenghua,Li Bo,Wang Jing,Liu Xiaojun,Zhao Wenfeng,Zhang Qingquan,Nie Xinming,Yu Yang
Isotropic silver nanoparticles (iAg NPs) can be easily prepared at low costs, have a low electrochemical potential and high extinction coefficient. An effective colorimetric assay for H 2 O 2 is reported here based on the finding that H 2 O 2 can induce the shape transformation of citrate-capped iAg NPs with the help of citrate. The substantial shape variation affords an apparent surface plasmon resonance (SPR) shift, accompanied by a vivid color change from light yellow to mauve. The color change can be observed visually if the concentration of H 2 O 2 is 2 μM or higher. A good linear relationship was obtained over the concentration range of 0.2–32 μM with a limit of detection of 90 nM. By making use of glucose oxidase, the method is further extended to glucose detection. Glucose at a concentration as low as 10 μM can be well determined with bare eyes. Benefitting from the high selectivity, the detection of glucose in human serum is realized, and the results are in good agreement with those provided by a clinical analyzer.
Schematic presentation of a colorimetric assay for H 2 O 2 and glucose based on citrate-promoted H 2 O 2 -mediated shape transformation of the isotropic silver nanoparticles (Ag NPs). The shape variation of isotropic Ag NPs induces a color change from light yellow to mauve.
研究领域:
分析化学
·
生物医学
·
纳米技术
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 7
·1-9
·
IF 5.705
Zhou Xiaotong,Wang Lumei,Shen Guoqing,Zhang Dongwei,Xie Jialun,Mamut Abdureyim,Huang Weiwen,Zhou Shanshan
A colorimetric method is presented for the determination of the antibiotic ofloxacin (OFL) in aqueous solution. It is based on the use of an aptamer and gold nanoparticles (AuNPs). In the absence of OFL, the AuNPs are wrapped by the aptamer and maintain dispersed even at the high NaCl concentrations. The solution with colloidally dispersed AuNPs remains red and has an absorption peak at 520 nm. In the presence of OFL, it will bind to the aptamer which is then released from the AuNPs. Hence, AuNPs will aggregate in the salt solution, and color gradually turns to blue, with a new absorption peak at 650 nm. This convenient and specific colorimetric assay for OFL has a linear response in the 20 to 400 nM OFL concentration range and a 3.4 nM detection limit. The method has a large application potential for OFL detection in environmental and biological samples.
Schematic of a sensitive and simple colorimetric aptasensor for ofloxacin (OFL) detection in tap water and synthesic urine. The assay is based on the salt-induced aggregation of gold nanoparticles which results in a color change from red to purple.
研究领域:
分析化学
·
纳米技术
·
环境科学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）