Table 1.

Atomic composition (at.%) of samples derived from X-ray photoelectron spectroscopy (XPS) analysis. The traces of sodium, chlorine, and phosphorus were detected but were not taken into account. PCL—polycaprolactone; PRP—platelet-rich plasma.

Sample Name	C	O	N	S
PCL-ref	73.9	26.1	0.0	0.0
PCL-PRP	71.6	20.6	7.6	0.2
PCL-COOH	72.4	26.7	0.9	0.0
PCL-COOH-PRP1	71.3	18.5	10.0	0.2
PCL-COOH-PRP2	75.8	18.1	5.9	0.2