A fluorescent sensor for discrimination of HSA from BSA through selectivity evolution.

Area of Science:

• Biochemistry
• Analytical Chemistry
• Biomedical Engineering

Background:

• Quantitative detection of Human Serum Albumin (HSA) is crucial for pre-clinical diagnosis of numerous diseases.
• Existing methods for HSA detection may lack selectivity or sensitivity, necessitating improved diagnostic tools.

Purpose of the Study:

• To develop a highly selective and sensitive sensor for the quantitative detection of Human Serum Albumin (HSA).
• To evaluate the sensor's performance characteristics and its potential for biological applications.

Main Methods:

• A high-selectivity HSA sensor, RhHSA, was developed using a two-round selectivity evolution strategy.
• Sensor performance was assessed for selectivity, sensitivity, stability, and linear range.
• Mechanism of action was investigated through HSA destruction, site competition, and molecular docking.
• In vitro and in vivo studies were conducted using cell-based assays and urine samples.

Main Results:

• RhHSA demonstrated high selectivity for HSA over Bovine Serum Albumin (BSA) (approx. 6-fold).
• The sensor exhibited high sensitivity with a limit of detection (LOD) of ~5 nM, a 700-fold enhancement.
• RhHSA showed excellent stability over 24 hours and a wide linear range (0-0.5 mg/mL).
• Molecular docking indicated RhHSA binds to ibuprofen and phenylbutazone sites on HSA, explaining its specificity.
• The sensor performed effectively in cell-based fluid replacement assays and urine sample analysis.

Conclusions:

• RhHSA is a highly selective and sensitive sensor for quantitative HSA detection.
• The sensor's robustness and wide linear range make it suitable for conventional HSA measurements.
• RhHSA shows significant potential for diverse biological applications, including disease diagnosis.