SYNTHESIS OF POLIVINYL ALCOHOL/GUAVA LEAVES EXTRACT (PSIDIUM GUAJAVA LINN) BY FREEZE THAW TECHNIQUE AS A WOUND DRESSING

• Main Author: Xaveriano Waresindo, William
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/52017
• Institution: Institut Teknologi Bandung

Hydrogels are three-dimensional polymeric networks that can absorb large amounts of liquid. Hydrogel synthesis can be carried out by physical or chemical crosslinking methods with natural and synthetic polymers as the primary ingredients. As a type of synthetic polymer, PVA has the advantage of being biocompatible and biodegradable so that it is widely applied in the biomedical field. PVA hydrogel can be composited with active ingredients with an antibacterial activity to be applied as a wound cover. The active ingredient relatively evenly distributed in Indonesia and has been widely used as traditional medicine is the guava plant, especially the leaves. In this study, the synthesis of PVA hydrogel was composited with guava leaf extract (EDJB) using the physical crosslinking method (freeze-thaw). The research started with guava leaf extraction, synthesis of PVA and EDJB solutions, and synthesis of PVA/EDJB hydrogels using the freeze-thaw method. Measurement and characterization begin with measuring solution parameters (viscosity and density), hydrogel density, hydrogel morphology, degree of expansion and weight loss, functional groups, and hydrogel crystallinity. Measurement of the solution's viscosity and density shows a decreasing trend in value when the EDJB concentration increases. PVA/EDJB hydrogel morphology characterized using SEM showed differences in pore size. Hydrogel pore size increased with the addition of EDJB in the hydrogel sample. The pore sizes of hydrogel PVA/EDJB S0, S1, S2, S3, S4, and S5 hydrogel samples were 14.62 ?m; 19.19 ?m; 21.97 ?m; 25.18 ?m; 33.25 ?m, and 43.38 ?m. The increase in pore size is accompanied by an increase in the value of the degree of development. The S5 sample with the largest pore size could absorb the PBS solution and expand up to 208% of the original size. The degree of swelling increases with the decrease in weight experienced by the hydrogel sample. The more EDJB concentration causes a decrease in the concentration of PVA so that the hydrogel sample with the more significant the EDJB concentration has decreased weight. The reduction in sample weight for S5 was 25.88% because the EDJB content in the sample was dissolved, and the color of the PBS solution became increasingly concentrated. The results of FTIR analysis showed the presence of functional groups from the two precursors (PVA and EDJB) on the synthesized hydrogel. The addition of EDJB concentration causes the absorbance peak on the FTIR graph to widen due to the formation of hydrogen bonds during the freeze-thaw process. The crystallinity of the samples characterized using XRD showed that the crystalline phase transformed into amorphous in the PVA/EDJB hydrogel sample when the EDJB concentration was increased. DSC characterization showed significant shrinkage of the hydrogel weight from a temperature of 30 ? - 150 ? due to the water content's evaporation in the hydrogel matrix. The variation in the composition of the EDJB causes a decrease in the melting temperature to a lower temperature. The degree of crystallinity calculated based on the melt's heating value shows a decreasing trend in value with the addition of EDJB. The compression modulus and compressive strength of the hydrogel decreased due to the reduced PVA concentration. The zone of inhibition produced by the PVA/EDJB hydrogel increased with the addition of EDJB. Antibacterial activity against S. aureus bacteria was 16,75%/gram, and 16,97%/gram against P. aeruginosa. PVA/EDJB composite hydrogel has the potential to be a wound dressing because it can absorb extensive wound exudates, good mechanical properties, and high antibacterial value.