Fluorescent sensor array for discrimination of biothiols based on poly(thymine/cytosine)-templated copper...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Nanotechnology

Background:

• Biothiols play vital roles in biological processes, necessitating accurate detection methods.
• Existing methods for biothiol identification can be complex or lack sensitivity.
• Developing rapid and effective biothiol detection is crucial for medical diagnostics.

Purpose of the Study:

• To develop a facile, rapid, and effective sensor array for identifying five common biothiols.
• To utilize fluorescent copper nanoparticles (CuNPs) templated by single-stranded DNA for biothiol detection.
• To establish a unique fluorescence response pattern for distinguishing between different biothiols.

Main Methods:

• Fabrication of a sensor array using poly(thymine/cytosine)-templated fluorescent copper nanoparticles (CuNPs).
• Control of CuNP formation via thymine-Hg²⁺-thymine and cytosine-Ag⁺-cytosine coordination.
• Utilizing ascorbic acid as a reductant for CuNP synthesis.
• Analysis of fluorescence variations using Linear Discriminant Analysis (LDA).

Main Results:

• The sensor array successfully generated unique fluorescence patterns upon interaction with five biothiols: glutathione (GSH), l-cysteine (Cys), dithiothreitol (DTT), 2-mercaptoethanol (MCE), and 3-mercaptopropionic acid (MPA).
• Differential thiol binding affinities of Hg²⁺ and Ag⁺ were exploited to differentiate biothiols.
• LDA effectively analyzed fluorescence data, creating a clustering map for clear identification.
• Successful discrimination of the five thiols at concentrations as low as 50 nM in both buffer solutions and serum samples.

Conclusions:

• The developed "turn-on" sensor array provides a highly efficient method for discriminating between multiple biothiols.
• The sensor demonstrates excellent sensitivity and applicability in complex biological matrices like serum.
• This approach offers a promising tool for the sensitive and selective detection of biothiols in biomedical applications.