A Highly Selective Mn(II)-Specific DNAzyme and Its Application in Intracellular Sensing

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Manganese (Mn²⁺) is vital for human enzymes and metabolism.
• Detecting intracellular Mn²⁺ is challenging due to paramagnetic quenching and poor selectivity of existing fluorescent sensors.
• Distinguishing Mn²⁺ from similar ions like Ca²⁺ and Mg²⁺ remains difficult.

Purpose of the Study:

• To develop a highly selective and sensitive fluorescent sensor for intracellular Mn²⁺ detection.
• To overcome the limitations of existing sensors in biological environments.
• To enable monitoring of Mn²⁺ in cellular processes and nanomaterial degradation.

Main Methods:

• In vitro selection of an RNA-cleaving DNAzyme with high Mn²⁺ selectivity.
• Development of a catalytic beacon approach for fluorescent sensing.
• Application of the sensor in immune and tumor cells.
• Monitoring degradation of manganese oxide (MnOx) nanomaterials.

Main Results:

• An RNA-cleaving DNAzyme with exceptional Mn²⁺ selectivity was identified.
• A novel fluorescent sensor was created using the DNAzyme and a catalytic beacon.
• Successful Mn²⁺ sensing was demonstrated in immune and tumor cells.
• The sensor effectively monitored the degradation of MnOx nanomaterials in tumor cells.

Conclusions:

• The developed DNAzyme-based fluorescent sensor offers high selectivity for Mn²⁺ detection.
• This sensor is a valuable tool for studying Mn²⁺ in biological systems.
• It facilitates monitoring of Mn²⁺-related immune responses and antitumor therapies.