Table 2.

Water contact angle (in degrees) of the substratum, and surface hydrophobicity parameters (in mJ/m²)

Surface	Water contact angle (±SD)	${\gamma }_{\text{S}}^{\text{LW}}$	${\gamma }_{\text{S}}^{+}$	${\gamma }_{\text{S}}^{-}$	$\Delta G_{\text{iwi}}^{\text{TOT}}$
Glass	23.0 (2.2)	34.53	2.72	45.46	19.98
Acrylic	85.5 (2.2)	38.06	0	7.59	−50.82

SD means standard deviation; ${\gamma }_{\text{S}}^{\text{LW}}$ represents the apolar Lifshitz–van der Waals surface free energy component; ${\gamma }_{\text{S}}^{+}$ represents the electron acceptor surface free energy component; ${\gamma }_{\text{S}}^{-}$ represents the electron donator surface free energy component; $\Delta G_{\text{iwi}}^{\text{TOT}}$ represents the degree of hydrophobicity.