Composite Hydrogel
of Poly(vinyl alcohol) Loaded by Citrus hystrix Leaf Extract, Chitosan, and Sodium
Alginate with In Vitro Antibacterial and Release Test
posted on 2024-03-05, 13:37authored byKusjuriansah Kusjuriansah, Marathur Rodhiyah, Nabila Asy Syifa, Halida Rahmi Luthfianti, William Xaveriano Waresindo, Dian Ahmad Hapidin, Tri Suciati, Dhewa Edikresnha, Khairurrijal Khairurrijal
Citrus hystrix leaves
have been
used traditionally as a spice, a traditional medicine for respiratory
and digestive disorders, and a remedy for bacterial infections. This
study reports on the synthesis of composite hydrogels using the freeze–thaw
method with poly(vinyl alcohol) (PVA) as the building block loaded
by C. hystrix leaf extract (CHLE).
Additionally, chitosan (CS) and sodium alginate (SA) were also loaded,
respectively, to increase the antibacterial activity and to control
the extract release of the composite hydrogels. The combinations of
the compositions were PVA, PVA/CHLE, PVA/CHLE/CS, PVA/CHLE/SA, and
PVA/CHLE/SA/CS. The internal morphology of the hydrogels shows some
changes after the PVA/CHLE hydrogel was loaded by CS, SA, and SA/CS.
The analysis of the Fourier transform infrared (FTIR) spectra confirmed
the presence of PVA, CHLE, CS, and SA in the composite hydrogels.
From the X-ray diffraction (XRD) characterization, it was shown that
the composite hydrogels maintained their semicrystalline properties
with decreasing crystallinity degree after being loaded by CS, SA,
and SA/CS, as also supported by differential scanning calorimetry
(DSC) characterization. The compressive strength of the PVA/CHLE hydrogel
decreases after the loading of CS, SA, and SA/CS, so that it becomes
more elastic. Despite being loaded in the composite hydrogels, the
CHLE retained its antibacterial activity, as evidenced in the in vitro
antibacterial test. The loading of CS succeeded in increasing the
antibacterial activity of the composite hydrogels, while the loading
of SA resulted in the decrease of the antibacterial activity. The
release of extract from the composite hydrogels was successfully slowed
down after the loading of CS, SA, and SA/CS, resulting in a controlled
release following the pseudo-Fickian diffusion. The cytotoxic activity
test proved that all hydrogel samples can be used safely on normal
cells up to concentrations above 1000 μg/mL.