A Simple Ratiometric Electrochemical Aptasensor Based on Exonuclease III-Assisted Target Recycling for Ultrasensitive Detection of Prostate Specific Antigen

Table 2

Electrochemical detection of PSA in human serum samples.

Sample	Added CEA	Detected CEA	Recovery (%)	RSD (%)
1	5.00 ng·mL^−1	4.91 ng·mL^−1	98.2	3.4
2	1.00 ng·mL^−1	0.89 ng·mL^−1	89.0	4.6
3	100.00 pg·mL^−1	102.30 pg·mL^−1	102.3	2.1