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Creation of Linear Carbon Dot Array with Improved Optical Properties through Controlled Covalent Conjugation with DNA.

ABSTRACT: Controlled conjugation of fluorescent carbon dots (CDs) with DNA and subsequent fabrication of the CDs into an array through hybridization mediated self-assembly in the solution phase is reported. Covalent conjugation of CD with DNA and the subsequent array formation change the mobility of the CD-DNA array in gel electrophoresis and HPLC significantly. Interspatial distance in the CD-DNA array is tuned by the DNA sequence length and maintained at ?8 ± 0.3 nm as revealed by electron microscopy studies. An increase in fluorescence lifetime by ?2 ns was observed for the CD-DNA array compared to a solitary CD, vis-á-vis better imaging prospects of HEK293 cells by the former. Thus, the array displays improved fluorescence and unhindered cell penetration.

SUBMITTER: Kumari S

PROVIDER: S-EPMC7116061 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Creation of Linear Carbon Dot Array with Improved Optical Properties through Controlled Covalent Conjugation with DNA.

Kumari Sonam S Solanki Apurv A Mandal Saptarshi S Subramanyam Deepa D Das Prolay P

Bioconjugate chemistry 20180412 5

Controlled conjugation of fluorescent carbon dots (CDs) with DNA and subsequent fabrication of the CDs into an array through hybridization mediated self-assembly in the solution phase is reported. Covalent conjugation of CD with DNA and the subsequent array formation change the mobility of the CD-DNA array in gel electrophoresis and HPLC significantly. Interspatial distance in the CD-DNA array is tuned by the DNA sequence length and maintained at ∼8 ± 0.3 nm as revealed by electron microscopy st ...[more]

PMID: 29634254

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