Development of an optical RNA-based aptasensor for C-reactive protein

Area of Science:

• Biomedical Engineering
• Molecular Diagnostics
• Biochemistry

Background:

• C-reactive protein (CRP) is a crucial clinical biomarker for inflammation and tissue damage.
• CRP levels elevate during various conditions like infection, trauma, and myocardial infarction, indicating its prognostic value.
• Existing detection methods may lack the sensitivity or specificity required for early diagnosis.

Purpose of the Study:

• To develop and optimize an RNA aptamer-based optical biosensor (aptasensor) for sensitive and selective C-reactive protein (CRP) detection.
• To investigate the critical parameters influencing aptasensor performance, including aptamer immobilization and binding conditions.
• To evaluate the aptasensor's potential for detecting CRP in complex biological matrices like human serum.

Main Methods:

• Design and synthesis of a 44-base RNA aptamer targeting CRP.
• Optimization of aptamer immobilization strategies (chemistry, length, concentration) on the sensor surface.
• Systematic evaluation of binding conditions, including buffer composition, Ca2+ ion presence, and specificity against human serum albumin (HSA).
• Characterization of the aptasensor using optical detection principles.

Main Results:

• The optimized aptasensor achieved a low detection limit of 0.005 ppm for CRP.
• Demonstrated high selectivity for CRP over a potential interfering protein, human serum albumin.
• Preliminary experiments showed promising results for CRP detection in undiluted human serum samples.

Conclusions:

• The developed RNA aptamer-based optical biosensor offers a sensitive and selective platform for CRP detection.
• The study highlights the importance of optimizing immobilization and binding conditions for aptasensor performance.
• This aptasensor holds potential for point-of-care diagnostics and monitoring inflammatory conditions.