Colorimetric Nitrite and Nitrate Detection with Gold Nanoparticle Probes and Kinetic End Points

Daniel, Weston L.; Han, Min Su; Lee, Jae Seung; Mirkin, Chad A.

doi:10.1021/ja901609k

Cited by 323 publications

(181 citation statements)

References 27 publications

Supporting

Mentioning

179

Contrasting

Order By: Relevance

“…Dispersed gold nanoparticles can be used as basis for sensitive colorimetric probes. 57 In this experiment, the two free thiol groups of hexanedithiol can bind two or more gold nanoparticles together. This leads to a gradual aggregation of the nanoparticles, which can be monitored via the optical response.…”

Section: ■ Results and Discussionmentioning

confidence: 98%

Multiscattering-Enhanced Absorption Spectroscopy

2015

View full text Add to dashboard Cite

An original scheme for sensitive absorption measurements, particularly well-suited for low analyte concentrations, is presented. The technique is based on multiscattering-enhanced absorption spectroscopy (MEAS) and benefits from the advantages of conventional absorption spectroscopy: simplicity, rapidity, and low costs. The technique relies on extending the optical path through the sensing volume by suspending dielectric beads in the solution containing the analytes of interest, resulting in multiple scattering of light, which increases the optical path length through the sample. This way, a higher sensitivity and lower limit of detection, compared to those of conventional absorption spectroscopy, can be achieved. The approach is versatile and can be used for a broad variety of analytes. Here, it is applied to the detection of phenol red, 10 nm gold nanoparticles, and envy green fluorescence dye; the limit of detection is decreased by a factor of 7.2 for phenol red and a factor of 3.3 for nanoparticles and dye. The versatility of this approach is illustrated by its application in increasing the sensitivity of colorimetric detection with gold nanoparticle probes and a commercially available hydrogen peroxide bioassay. The influence of different parameters describing the scattering medium is investigated in detail experimentally and numerically, with very good agreement between the two. Those parameters can be effectively used to tailor the enhancement for specific applications and analytes.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 98%

Multiscattering-Enhanced Absorption Spectroscopy

2015

View full text Add to dashboard Cite

show abstract

“…Most of them include chromogenic sensors (Banthia and Samanta 2005), Chemodosimeter-functionalized sensor (Kim et al 2008a, b), fluorescent chemosensor (Zhang et al 2011), atomic absorption spectroscopy (Gonzales et al 2009), inductively coupled plasma mass spectroscopy (Backer et al 2005) and inductively coupled plasma atomic emission spectroscopy (Liu et al 2005 (Zhao et al 2008) such as viruses (Niikura et al 2009), cancerous cells (Midley et al 2008), toxins (Uzawa et al 2008), heavy metals (Barman et al 2014a, b;Fan et al 2009), pesticides Maiti et al 2013;Dasary et al 2009), many inorganic and organic pollutants in water (Daniel et al 2009;Xiao and Yu 2010). The methods of determination rely on their unique size and interparticle distance-dependent absorption spectra and color change of the solution.…”

Section: Hgmentioning

confidence: 99%

Detection of heavy metals (Cu+2, Hg+2) by biosynthesized silver nanoparticles

2015

View full text Add to dashboard Cite

Here, we are reporting two methods for detection of Cu ?2 ion and Hg ?2 ions using biosynthesized silver nanoparticles. The detection of Cu ?2 ion was based on changes in absorbance resulting from complex formation of the metal ion. Various concentrations of Cu ?2 ion were used to test the linearity and sensitivity of the method. A new peak at around 770 nm, in addition to the peak of the AgNP at 406 nm, was observed in each case (above 20 lM). With the increase of concentration of Cu ?2 ion solution, the absorbance at 406 nm peak decreased and that of 770 nm increased gradually. The calibration curve obtained from the ratio of the absorption coefficients of these two peaks (Ex 770/406 ) versus concentration of Cu ?2 ions enables one to estimate quantitatively the amount of Cu ?2 ions present in water in lM levels. This AgNP was further functionalized with 3-mercapto-1, 2-propanediol (MPD) for detection of Hg ?2 present in water by colorimetric method. As soon as Hg ?2 solution was added in MPDfunctionalized AgNP (MPD-AgNP), a new peak at around 606 nm appeared along with the peak at 404 nm. The new peak might be due to the aggregations occurred by the recognition of heavy metal ion Hg ?2 by MPD-AgNP through dipropionate ion. A calibration curve between the ratios of the absorption coefficients of these two peaks (Ex 404/606 ) and concentration of Hg ?2 was drawn for quantitative estimation of Hg ?2 present in water at lM level.

show abstract

“…147,148 The AuNPs containing a novel p-sulfonatocalix [4]arene derivative attached to the gold surface via thiol groups (103, Figure 38) were used as colorimetric probe for the detection of A second example that uses selective aggregation of AuNPs is based on the Griess reaction for the selective detection of NO 2 -anion ( Figure 39). 150 Two types of AuNPs were prepared, AuNPs containing aniline groups (104) and AuNPs containing naphthalene moieties (105). The aniline-and naphthalene-capped AuNPs are red when dispersed in aqueous solution due to an intense surface plasmon resonance at 520 nm.…”

Section: Anion Anionmentioning

confidence: 99%