Covalently-linked Adducts of Single-walled Nanotubes with Biomolecules: Synthesis, Hybridization, and Biologically-Directed Surface Assembly

ABSTRACTCovalently-linked adducts of single-walled carbon nanotubes (SWNTs) with biomolecules have been fabricated. Results are presented here for DNA-SWNT and for biotin-SWNT adducts. DNA-SWNT adducts are shown to be biochemically accessible and to exhibit high selectivity, favoring hybridization with complementary vs. non-complementary DNA sequences. Biotin-SWNT adducts were also prepared and used to direct the assembly of nanotubes onto a biotinylated glass surface.

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Single walled carbon nanotubes functionalized with nickel phthalocyanines: effects of point of substitution and nature of functionalization on the electro-oxidation of 4-chlorophenol

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424611004439 ◽

2012 ◽

Vol 16 (01) ◽

pp. 130-139 ◽

Cited By ~ 7

Author(s):

Samson Khene ◽

Tebello Nyokong

Keyword(s):

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

Current Response ◽

Single Walled Carbon ◽

Nickel Phthalocyanine ◽

Phthalocyanine Complex ◽

Electro Oxidation ◽

Covalently Linked ◽

Walled Carbon Nanotubes ◽

Hydroxy Groups

In this work we report on electrochemical behavior of nickel phthalocyanine derivatives tetrasubstituted peripherally and non-peripherally with hydroxy and used to modify single walled carbon nanotubes. Nickel phthalocyanine complex octasubstituted at the peripheral positions with hydroxy groups was also used to modify single walled carbon nanotubes. Nickel phthalocyanine complex tetrasubstituted with amino groups at peripheral position was covalently and non-covalently linked to single walled carbon nanotubes. All the conjugates of nickel phthalocyanine derivatives with single walled carbon nanotubes were used for the electro oxidation of 4-chlorophenol. The nickel phthalocyanine octabsubstituted with hydroxy groups at the non-peripheral positions gave the best current response and the best resistance against electrode fouling for the oxidation of 4-chlorophenol.

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The Long-Term Fate and Toxicity of PEG-Modified Single-Walled Carbon Nanotube Isoliquiritigenin Delivery Vehicles in Rats

Journal of Nanomaterials ◽

10.1155/2014/257391 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Bo Han ◽

Mingming Zhang ◽

Ting Tang ◽

Qiusheng Zheng ◽

Keyu Wang ◽

...

Keyword(s):

Carbon Nanotubes ◽

Molecular Weight ◽

Single Walled Carbon Nanotubes ◽

Blood Clearance ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon ◽

Tissue Sections ◽

Covalently Linked ◽

Walled Carbon Nanotubes

Oxidized single-walled carbon nanotubes (o-SWNTs) was modified by covalently and noncovalently linking PEG to the o-SWNTs. The influence of oxidation time, PEG molecular weight, and type of PEG linkage on the blood clearance time of PEG-modified single-walled carbon nanotubes (SWNTs) was investigated. The toxicity profile of SWNTs covalently linked to PEG (c-PEG-o-SWNTs) in rats has also been determined. The pharmacokinetics of c-PEG-o-SWNTs in rats and their distribution in vital organs were monitored by Raman spectroscopy, and the blood clearance of homogenate isoliquiritigenin (ISL) was determined by HPLC. Photos of tissue and tissue sections were taken to evaluate the toxicity of c-PEG-o-SWNTs. We found that SWNTs which were covalently modified with PEG and have a molecular weight of 3500 had the longest blood clearance half-lives. However, SWNTs were toxic to the kidneys and the hearts. The high renal clearance of long-term fate SWNTs may occur because of impaired kidney filtration function. Therefore, we assume that while researchers study the long-term fate of SWNTs, the toxicity of SWNTs also needs to be taken into account.

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