A Turn-On Resonance Raman Scattering (BCS/Cu+) Sensor for Quantitative Determination of Proteins

Area of Science:

• Analytical Chemistry
• Spectroscopy

Background:

• Accurate protein quantification is crucial in biological and clinical research.
• Existing methods like colorimetric and UV-based assays have limitations in sensitivity and detection range.

Purpose of the Study:

• To develop a novel, highly sensitive method for quantitative protein evaluation.
• To improve the lower limit of detection and broaden the detectable concentration range for protein assays.

Main Methods:

• Utilized competitive resonance Raman spectroscopy.
• Employed a chelation reaction between bathocuproine disulfonate (BCS) and Cu(+) reduced by proteins.
• Created a BCS-Cu(+) complex with strong resonance Raman activity.

Main Results:

• Achieved a lower limit of detection of 500 pg/mL, surpassing conventional methods.
• Enabled protein detection over a significantly wider concentration range.
• Demonstrated high accuracy and excellent protein recovery in real samples like fetal bovine serum (FBS).

Conclusions:

• The proposed resonance Raman spectroscopy method is a novel and highly sensitive protocol for protein assays.
• This method offers superior performance compared to existing colorimetric and UV-based techniques.
• The technique is accurate for determining total protein concentrations in complex biological samples.