Antibacterial Functionally Graded Composite Membrane for Periodontal Regeneration

Abstract

Periodontitis is a gum disease caused by bacterial infections. It damages the soft and hard tissues that clasped teeth position and leads to teeth loss. Periodontal disorder affects 90% of people throughout the world. A functionally graded membrane having mechanical strength, porosity, and good regeneration capability of hard and soft tissue of periodontal offers effective recovery In this study, an antibacterial, functionally, and structurally graded bilayer membrane was synthesized by using a greener crosslinker 2,3- dialdehyde cellulose (DAC). Chitosan (CH), Oval albumin (OA), and crosslinker DAC were used to fabricate the membrane for the soft tissue regeneration. The CH, OA Hydroxyapatite (HA), and Copper substituted hydroxyapatite (Cu-HA) were used to prepare membrane for the growth of hard tissue. To install antibacterial properties and improve biological activity in the proposed membrane HA was substituted with copper. The biopolymer used in this study possesses good regeneration ability. CS is the second most abundant natural biopolymer well known for its biocompatibility, bioactivity. Oval albumin reported to activate cellular adhesion and regenerations. Crosslinker dialdehyde cellulose offers good biocompatibility compared to commonly used toxic poly aldehyde-based crosslinkers. HA is a gold standard biomineral having an excellent ability to regenerate hard tissue. Oxidation of cellulose to dialdehyde cellulose was done by using NaIO4. Four different membrane samples with different amounts of crosslinkers were prepared to evaluate the effect of crosslinkers on membrane strength and biological properties. Prepared samples are named as M: DAC5%, M: DAC10%, M: DAC15%and M: DAC20%. Where M is represented CH and OA. Equal amount of both polymers was used. Crosslinker % was with respect to polymeric matrix. HA and CU-HA are synthesized via the economical co-precipitation method. FT-IR and XRD analysis showed the successful synthesis of HA and Cu-HA. XRD analysis also confirmed the phase pure preparation of Cu substituted HA crystal There is no secondary phase appeared in XRD spectra of HA and Cu-HA. EDS results also supported copper substitution. Porous membranes for hard tissues regeneration were prepared by using prepared HA or Cu-HA with CS and OA. The freeze gelation method was used for the fabrication of membranes. These membranes are named as is M: HA and M: Cu-HA. Two bilayer membranes were prepared by using M: DAC15% as a first layer and second layer M: HA or ME: Cu-HA. These samples are name as Bi-MDAC%15-HA and Bi-MDAC%15-CuHA. The second layer was fabricated over the first layer. Physical and biological tests of the membranes were performed to evaluate the performance of prepared membrane samples. Swelling analysis of membrane showed the good swelling property in PBS solution. Swelling is slightly decreased with increasing the crosslinker content. Biodegradation analyses indicated that 45% degradation occurs up to fourteen. The chance of infection is a major reason for implant failure. Prepared Copper substituted hydroxyapatite Cu-HA and membrane containing Cu-HA showed effective antibacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus). Thermal analysis of bilayer membranes shows that the membranes lost their 50-54% weight at 10000C temperature. SEM analysis shows that the upper layer of the soft tissues is smooth but there are some particles of cellulose while the lower layer of the membrane has particles of HA/ Cu-HA. The contact angle of the soft tissue membrane shows prepared membrane are hydrophilic. Prepared Membranes showed non-toxic behavior and supported cell proliferation of NIH3T3 cells monitored by Alamar blue assay and wound healing Assay. Wound healing assay revealed good regenerative capacity of prepared bilayer Bi-DAC%15-HA and Bi-DAC%15-Cu-HA. Substitution of copper in HA further improved the healing capacity. It is concluded that prepared bilayer membrane can be used as a potential candidate for regenerations of periodontal defects.