Biological investigation using a shear horizontal surface acoustic wave sensor: small "click generated" DNA...

Area of Science:

• Biosensor technology
• Nanotechnology
• Molecular biology

Background:

• Surface Acoustic Wave (SAW) sensors offer high sensitivity for detecting molecular interactions.
• DNA hybridization is a fundamental process in molecular biology with applications in diagnostics and research.
• Investigating novel DNA analogues and their interaction with natural DNA is crucial for advancing biosensing capabilities.

Purpose of the Study:

• To investigate DNA probe grafting and hybridization using a lithium tantalate (LiTaO3) SAW sensor.
• To explore the hybridization efficiency of natural DNA with click-generated (Cg-DNA) oligonucleotides.
• To determine the recognition length and bond stability of synthesized DNA analogues compared to natural DNA.

Main Methods:

• Utilized a 104 MHz lithium tantalate (LiTaO3) surface acoustic wave (SAW) sensor.
• Tested hybridization with natural DNA targets and synthesized tosyl- and azido-thymidine oligonucleotides of varying lengths.
• Analyzed frequency responses to quantify grafting and hybridization kinetics.

Main Results:

• Successfully detected DNA probe grafting and hybridization using the SAW sensor.
• Identified complementarity between natural DNA probes and azido-tetra-thymidine for the first time, extending beyond the previously reported 10-mer minimum recognition length.
• Demonstrated that synthesized oligonucleotides form stable bonds with complementary DNA strands, unlike natural DNA.
• Observed similar exponential decay in frequency response for both grafting and hybridization, with distinct time constants.

Conclusions:

• The SAW sensor effectively monitors DNA grafting and hybridization processes.
• Synthesized azido-thymidine oligonucleotides show promising stable hybridization with natural DNA, even at short lengths.
• This advancement in DNA sensing opens new avenues for molecular diagnostics and synthetic biology applications.