Photochemically Triggered Alkylthiol Reactions on Highly Ordered Pyrolytic Graphite

Soldi, Laura; Cullen, Ronan J.; Jayasundara, Dilushan R.; Scanlan, Eoin M.; Giordani, Silvia; Colavita, Paula E.

doi:10.1021/jp2024582

Cited by 11 publications

(14 citation statements)

References 98 publications

(156 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The functionalization of photochemically modified hydrogen‐terminated diamond surfaces is a surface‐mediated photochemical reaction, and it is initiated by electron photoejection from the surfaces, with generation of positive holes . The surface of highly ordered pyrolytic graphite was photochemically modified with thiols, and the mechanism was proposed to proceed via photoinduced electron transfer from the graphite to the substrates to form highly reactive alkyl radicals . The photolysis of hydrogen‐terminated carbon surfaces with substituted alkenes is triggered by electron photoemission from the solid into the acceptor levels of the alkenes .…”

Section: Results and Discusionmentioning

confidence: 99%

Effect of mass of pristine carbon nanotubes on the photolysis of phenylalanine

Humeres

Souza

Debacher

et al. 2018

J of Physical Organic Chem

View full text Add to dashboard Cite

Photolyses at 254 nm of aqueous solutions of phenylalanine (Phe) were carried out at 25°C in the absence and presence of multiwalled carbon nanotubes (CNT). The photolyses were performed in distilled, deoxygenated water and inert Ar atmosphere or in distilled water and air atmosphere. Kinetics of the photolyses were followed by UV spectrophotometry at 220 nm. Initial rates were obtained from the plot of ΔA versus Δt, both in the presence of CNT (ΔA/Δt = p*) and in their absence (ΔA/Δt = po*). The ratio p*/ po* gave the ratio k*/ ko* of the rate constants of the photolysis in the presence and in the absence of nanotubes, respectively. The mass of nanotubes produced an exponential attenuation of the photolytic decomposition of Phe with minor formation of tyrosine and an attenuation constant κ of the shielding effect of the nanotubes against the photolytic degradation of the amino acid. The results show the effects of CNT on the photolysis of Phe and support the previously observed attenuation effect of carbons on the denaturalizatoion of amino acids and proteins. It is concluded that carbons produce a shielding effect on the photolysis, absorbing the photons and decreasing substantially their denaturalization while at the same time excites the active sites of the carbon for the insertion reaction of the organic moiety.

show abstract

Section: Results and Discusionmentioning

confidence: 99%

Effect of mass of pristine carbon nanotubes on the photolysis of phenylalanine

Humeres

Souza

Debacher

et al. 2018

J of Physical Organic Chem

View full text Add to dashboard Cite

show abstract

“…[11] Hydrogen-terminated substrates have found applications in the highly stable photofunctionalization of surfaces with alkenes, [1,12] azides, [13] and alkylthiols. [14] Halogenation with thionyl chloride (SOCl 2 ) or phosphorus tri/pentachloride (PCl 3/5 ) in organic solvents has recently been reported as ways of increasing the reactivity of H-terminated surfaces. These brominated or chlorinated surfaces were then modified through the formation of CÀC bonds between the surface and different types of alkyl Grignard reagents [15] or alkylthiols, [9b] and the formed monolayers were demonstrated to be extremely stable even at temperatures above 200 8C.…”

Section: Introductionmentioning

confidence: 99%

“…This results in the formation of CH dipoles in which the electropositive H is slightly susceptible to nucleophilic attack 11. Hydrogen‐terminated substrates have found applications in the highly stable photofunctionalization of surfaces with alkenes,1, 12 azides,13 and alkylthiols 14…”

Section: Introductionmentioning

confidence: 99%

“…However, this chlorination process suffers from an inherent requirement for toxic materials as well as the difficulty of controlling the reaction, which can result in etching and damaging of the substrates 18. An alternative approach exploits the photochemical grafting of organic alkenes to link functional organic molecules to carbon surfaces including diamond,1 amorphous carbon,15a glassy carbon (GC),19 highly ordered pyrolitic graphite (HOPG),13a, 14 and carbon nanofibers 20. Recently, the feasibility of attaching iodine atoms to carbon films formed by photoresist pyrolysis with iodine plasma and the subsequent linking of both alkenes and alkynes to the iodinated surface has been demonstrated 21…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Facile Electrochemical Hydrogenation and Chlorination of Glassy Carbon to Produce Highly Reactive and Uniform Surfaces for Stable Anchoring of Thiolated Molecules

Debela

Ortiz

Beni

et al. 2014

Chemistry A European J

View full text Add to dashboard Cite

Carbon is a highly adaptable family of materials and is one of the most chemically stable materials known, providing a remarkable platform for the development of tunable molecular interfaces. Herein, we report a two-step process for the electrochemical hydrogenation of glassy carbon followed by either chemical or electrochemical chlorination to provide a highly reactive surface for further functionalization. The carbon surface at each stage of the process is characterized by AFM, SEM, Raman, attenuated total reflectance (ATR) FTIR, X-ray photoelectron spectroscopy (XPS), and electroanalytical techniques. Electrochemical chlorination of hydrogen-terminated surfaces is achieved in just 5 min at room temperature with hydrochloric acid, and chemical chlorination is performed with phosphorus pentachloride at 50 °C over a three-hour period. A more controlled and uniform surface is obtained using the electrochemical approach, as chemical chlorination is observed to damage the glassy carbon surface. A ferrocene-labeled alkylthiol is used as a model system to demonstrate the genericity and potential application of the highly reactive chlorinated surface formed, and the methodology is optimized. This process is then applied to thiolated DNA, and the functionality of the immobilized DNA probe is demonstrated. XPS reveals the covalent bond formed to be a C-S bond. The thermal stability of the thiolated molecules anchored on the glassy carbon is evaluated, and is found to be far superior to that on gold surfaces. This is the first report on the electrochemical hydrogenation and electrochemical chlorination of a glassy carbon surface, and this facile process can be applied to the highly stable functionalization of carbon surfaces with a plethora of diverse molecules, finding widespread applications.

show abstract

“…An alternative method is light-assisted chemisorption of functionalised alkanethiols 22 bearing positively charged amine groups (-NH 2 + ) that may promote surface adsorption of the negatively charged DNA origami assemblies. Here, the freshly cleaved basal plane HOPG surface was modified with cysteamine following reported protocols, 31 Figure 3F). …”

mentioning

confidence: 99%

Electronically addressable nanomechanical switching of i-motif DNA origami assembled on basal plane HOPG

et al. 2015

View full text Add to dashboard Cite

Here, a pH-induced nanomechanical switching of i-motif structures incorporated into DNA origami bound onto cysteamine-modified basal plane HOPG was electronically addressed, demonstrating for the first time the electrochemical read-out of the nanomechanics of DNA origami. This paves the way for construction of electrode-integrated bioelectronic nanodevices exploiting DNA origami patterns on conductive supports.

show abstract

Photochemically Triggered Alkylthiol Reactions on Highly Ordered Pyrolytic Graphite

Cited by 11 publications

References 98 publications

Effect of mass of pristine carbon nanotubes on the photolysis of phenylalanine

Effect of mass of pristine carbon nanotubes on the photolysis of phenylalanine

Facile Electrochemical Hydrogenation and Chlorination of Glassy Carbon to Produce Highly Reactive and Uniform Surfaces for Stable Anchoring of Thiolated Molecules

Electronically addressable nanomechanical switching of i-motif DNA origami assembled on basal plane HOPG

Contact Info

Product

Resources

About