Decoration of glassy carbon surfaces with dendrimer-encapsulated nanoparticles with a view to constructing bifunctional nanostructures

Ju, Heeyoung; Koo, Chong Min; Kim, Joohoon

doi:10.1039/c1cc14997k

Cited by 21 publications

(17 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[5,6,10] This control of stoichiometry removed the need to separate the nonluminescent large Au aggregates, [11][12][13][14][15] which contrasts with previous work. The Au nanoclusters were prepared by adjusting the ratio of Au to the dendrimer template to control the number of Au atoms encapsulated inside dendrimers.…”

Section: Introductionmentioning

confidence: 92%

Blue Luminescence of Dendrimer‐Encapsulated Gold Nanoclusters

et al. 2014

Self Cite

View full text Add to dashboard Cite

Direct evidence for the blue luminescence of gold nanoclusters encapsulated inside hydroxyl-terminated polyamidoamine (PAMAM) dendrimers was provided by spectroscopic studies as well as by theoretical calculations. Steady-state and time-resolved spectroscopic studies showed that the luminescence of the gold nanoclusters consisted largely of two electronic transitions. Theoretical calculations indicate that the two transitions are attributed to the different sizes of the gold nanoclusters (Au8 and Au13). The luminescence of the gold nanoclusters was clearly distinguished from that of the dendrimers.

show abstract

Section: Introductionmentioning

confidence: 92%

Blue Luminescence of Dendrimer‐Encapsulated Gold Nanoclusters

et al. 2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…The corresponding histogram of the particle size distribution of the Pt DENs indicates that the measured size ( i.e ., 1.5 ± 0.3 nm) of the Pt DENs is consistent with the theoretical size ( i.e ., 1.6 nm) of nanoparticles containing 147 atoms (Figure (b)) . These results suggest the synthesis of stabilized Pt nanoparticles via their encapsulation inside dendrimers . As shown in Scheme , the Pt DENs were used to modify the SPCE surface with penicillinase enzymes for the fabrication of a sensitive penicillin sensor (see the Experimental section for details).…”

Section: Methodsmentioning

confidence: 87%

Sensitive Electrochemical Penicillin Sensor Based on Screen‐printed Carbon Electrode Modified with Dendrimer‐encapsulated Pt Nanoparticles

Kim

2016

Bulletin Korean Chem Soc

Self Cite

View full text Add to dashboard Cite

Penicillin is a group of antibiotics classified specifically as β-lactam antibiotics due to the presence of a β-lactam ring in its molecular structure, and has been widely used since its discovery in 1928.1,2 The facile analysis of penicillin has thus been of importance in various fields of applications including medical science, medicine, pharmaceutical industry, food industry, and environmental monitoring.3-6 Several sensing strategies have been developed for the detection of penicillin; they can be categorized mainly into three general approaches. The first involves the use of pH-sensitive indicator dyes. This type of penicillin sensor is based on the enzymatic hydrolysis of penicillin to penicilloic acid, resulting in a pH change that is sensed optically by means of an acid-base indicator.3 The second approach utilizes pH glass electrodes. The principle in the operation of this penicillin sensor is that the pH glass electrode senses changes in the H + concentration resulting from the catalyzed hydrolysis of penicillin by penicillinase. 7 The final approach is based on the principle of the field effect in semiconductor structures. This type of penicillin sensor provides many advantages over the first two types, mostly due to its potential for miniaturization and integration and also due to its rapid response. However, the development of a sensitive penicillin sensor that allows the detection of small amounts of penicillin at low micromolar levels rapidly and inexpensively is critically needed in order to meet the practical needs in many fields of application such as pharmaceutical production, clinical analysis of antibiotic tablets, and food control. 5,8,9 In this context, we report an electrochemical penicillin sensor utilizing dendrimer-encapsulated Pt nanoparticles (Pt DENs) as electrocatalysts for the sensitive detection of penicillin. As illustrated in Scheme 1, the electrochemical penicillin sensor was prepared using a screen-printed carbon electrode (SPCE), on which both Pt DEN and penicillinase were immobilized. Upon the addition of penicillin, the immobilized penicillinase catalyzes the hydrolysis of penicillin to penicilloic acid, resulting in the production of H + ions which are electrochemically detected by means of the catalyzed electrochemical reduction of the generated H + ions on the Pt DEN-modified SPCE surface. Specifically, we synthesized Pt DENs containing an average of 147 atoms using amineterminated sixth-generation polyamidoamine dendrimers, which we denote as G6-NH 2 (Pt 147 ), and immobilized the Pt DENs with penicillinase enzymes onto SPCE surfaces. The resulting SPCE exhibited highly enhanced electrocatalytic activity for the electrochemical reduction of H + ions, leading to significantly increased cathodic current of H + . Especially, the Pt DEN-modified SPCE resulted in the electrochemical detection of penicillin as low as 0.1 μM, which allowed sensitive analysis of penicillin even in human blood serum.Figure 1(a) shows transmission electron microscopy (TEM) images of the as-synthe...

show abstract

“…We synthesized Au DENs containing an average of 200 Au atoms within G6‐NH 2 PAMAM dendrimers, which we denote as G6‐NH 2 (Au 200 ), in a similar manner as described in our previous studies (see the Experimental Section for details) 10, 27. Figure 1a shows TEM images of the as‐synthesized Au DENs, which represent nanoparticles barely aggregated and nearly monodispersed in size due to stabilization of the nanoparticles via their encapsulation inside dendrimers 10, 34.…”

Section: Resultsmentioning

confidence: 99%

“…Au DENs were synthesized according to the procedure reported previously 10, 27, 31. In brief, 200 molar equivalent amount of an aqueous 10 mM HAuCl 4 solution was mixed with an aqueous 10 μM G6‐NH 2 PAMAM dendrimer solution.…”

Section: Methodsmentioning

confidence: 99%

Enhanced Electrochemiluminescence of Luminol on Indium Tin Oxide Modified with Dendrimer‐Encapsulated Au Nanoparticles

2015

Self Cite

View full text Add to dashboard Cite

Enhanced electrochemiluminescence (ECL) of luminol was reported with the use of dendrimer‐encapsulated Au nanoparticle (Au DEN)‐modified ITOs in the presence of hydrogen peroxide, which was applied for sensitive ECL‐based electroanalysis of hydrogen peroxide. The enhanced ECL of luminol in the presence of hydrogen peroxide was attributed to facile electrochemical oxidation of luminol/hydrogen peroxide on the Au DEN‐modified ITOs at potentials as low as ∼0.4 V (vs. Ag/AgCl). Spooling ECL spectroscopy measurements indicated that the enhanced ECL emission of luminol/hydrogen peroxide system on the Au DEN‐modified ITOs originated from excited 3‐aminophthalate as same as that obtained on bare ITOs. Stability of Au DENs on ITO surfaces was also addressed and found to be closely related with the presence of chloride ions in electrolyte solutions.

show abstract

Decoration of glassy carbon surfaces with dendrimer-encapsulated nanoparticles with a view to constructing bifunctional nanostructures

Cited by 21 publications

References 20 publications

Blue Luminescence of Dendrimer‐Encapsulated Gold Nanoclusters

Blue Luminescence of Dendrimer‐Encapsulated Gold Nanoclusters

Sensitive Electrochemical Penicillin Sensor Based on Screen‐printed Carbon Electrode Modified with Dendrimer‐encapsulated Pt Nanoparticles

Enhanced Electrochemiluminescence of Luminol on Indium Tin Oxide Modified with Dendrimer‐Encapsulated Au Nanoparticles

Contact Info

Product

Resources

About