No abstract

The objective of this study was to develop the metronidazole loaded high and low methoxyl pectin films (HM-G-MZ and LM-G-MZ) for the treatment of periodontal disease. The films were prepared by pectin 3% w/v, glycerin 40% w/v, and metronidazole 5% w/v. The developed films were characterized by scanning electron microscope and evaluated for thickness, weight variation, and elasticity. The developed films showing optimal mechanical properties were selected to evaluate radial swelling properties, in vitro release of metronidazole and the antimicrobial activity against Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans by the disc diffusion method. The results demonstrated that LM-MZ and HM-G-MZ films were colorless and yellowish color, respectively, with the film thickness around 0.36–0.38 mm. Furthermore, both films exhibited good elasticity with low puncture strength (1.63 ± 0.37 and 0.84 ± 0.03 N/mm2, respectively) and also showed slight increase in radial swelling, so that they could be easily inserted and fitted into the periodontal pocket during a clinical use. However, HM-G-MZ showed a decrease in radial swelling after 1 h due to the film erosion. The in vitro release study of LM-G-MZ showed a burst release that was initially followed by a slow release rate profile, capable to maintain the therapeutic level in periodontal pocket for seven days, whereas HM-G-MZ showed an immediate release profile. The cumulative percentage of metronidazole release from HM-G-MZ was less than LM-G-MZ during the first 5 min as metronidazole was in a crystalline form inside HM-G-MZ film. For antimicrobial activity test, both films showed the inhibitory effect against P. gingivalis and A. actinomycetemcomitans, and there was no difference in the inhibition zone between LM-G-MZ and HM-G-MZ. The present study showed, for the first time, that low methoxyl pectin film containing glycerin and metronidazole could be potentially considered as a promising clinical tool for the drug delivery via intra-periodontal pocket to target an oral disease that is associated with polymicrobial infection.

In this study, hydrogel films composed of low methoxyl pectin (LMP), gelatin, and carboxymethyl cellulose (CMC) were fabricated. Glycerin was used as a plasticizer while glutaraldehyde (Glu) and calcium chloride (CaCl2) were used as crosslinking agents in film preparation. Hydrogel films were morphologically characterized and evaluated for mechanical properties. In addition, the investigations for fluid uptake ability, water retention capacity, water vapor transmission rate, and integrity value of the invented films were performed. The results showed that F-Glu-Ca-G30 film demonstrated superior properties when compared to other prepared films. It demonstrated a high percentage of elongation at break (32.80%), fluid uptake ability (88.45% at 2 h), water retention capacity (81.70% at 2 h), water vapor transmission rate (1889 g/m2/day), and integrity value (86.42%). F-Glu-Ca-G30 film was subsequently selected for 10% w/w povidone iodine (PI) loading and tested for anti-Staphylococcus aureus activity using an agar diffusion assay. Notably, F-Glu-Ca-G30-PI film demonstrated a dramatic ability to inhibit microbial growth, when compared to both a blank film and iodine solution control. Our LMP/gelatin/CMC hydrogel film promises to be an effective dressing material with high fluid absorption capacity, fluid holding ability, and water vapor transmission rate. Incorporation of antibiotics such as povidone iodine into the films conferred its antimicrobial property thereby highlighting its potential dermatological use. However, further clinical studies of the application of this hydrogel film as wound dressing material is recommended.

In this study, we aimed to develop a low-mexthoxyl pectin (LMP) from mango peel pectin through a de-esterification method for use as a film forming agent. The prepared de-esterified pectin (DP) was compared to commercial LMP (cLMP) which possessed a 29% degree of esterification (DE). Mango peel pectin was extracted from ripe Nam Dokmai mango peel using the microwave-assisted extraction method. Pectin derived from the mango peel was classified as a high mexthoxyl pectin (79% DE) with 75% of galacturonic acid (GalA) content. A de-esterification experiment was designed by central composite design to plot the surface response curve. Our prepared DP was classified as LMP (DE 29.40%) with 69% GalA. In addition, the Fourier-transform infrared spectrophotometer (FTIR) spectra of the DP were similar to cLMP and the pectin backbone was not changed by the de-esterification process. Strikingly, the cLMP and DP films showed non-significant differences between their physical properties (p > 0.05) with respect to the puncture strength (13.72 N/mm2 and 11.13 N/mm2 for the cLMP and DP films, respectively), percent elongation (2.75% and 2.52% for the cLMP and DP films, respectively), and Young’s modulus (67.69 N/mm2 and 61.79 N/mm2 for the cLMP and DP films, respectively). The de-esterified pectin containing clindamycin HCl (DPC) and low-methoxyl pectin containing clindamycin HCl (cLMPC) films demonstrated 93.47% and 98.79% of drug loading content. The mechanical properties of the cLMPC and DPC films were improved possibly due to their crystal structures and a plasticizing effect of clindamycin HCl loaded into the films. The DPC film exhibited a drug release profile similar to that of the cLMPC film. Our anti-bacterial test of the films found that the cLMPC film showed 41.11 and 76.30 mm inhibitory clear zones against Staphylococcus aureus and Cutibacterium acnes, respectively. The DPC film showed 40.78 and 74.04 mm clear zones against S. aureus and C. acnes, respectively. The antibacterial activities of the cLMPC and DPC films were not significantly different from a commercial clindamycin solution. The results of this study suggest that mango peel pectin can be de-esterified and utilized as an LMP and the de-esterified pectin has the potential for use as a film forming agent, similar to cLMP. In addition, the remarkable use of de-esterified mango peel pectin to prepare films, as shown by our study, holds a great promise as an alternative material for anti-bacterial purposes.