aDepartment of Pharmaceutical Chemistry,Faculty of Pharmacy,Rangsit University,Muang,Pathum Thani 12000,Thailand

bSino-Thai Traditional Medicine Research Center(Cooperation between Rangsit University,Harbin Institute of Technology,Heilongjiang University of Chinese Medicine),Faculty of Pharmacy,Rangsit University,Muang, Pathum Thani 12000,Thailand

cSun Herb Thai Chinese Manufacturing Plant,Faculty of Pharmacy,Rangsit University,Muang,Pathum Thani 12000,Thailand

Swelling behavior of polyvinyl alcohol and lactic acid hydrogel flms

Jirapornchai Suksaereea,b,*,Chitradee Luprasongc,Chaowalit Montonb

aDepartment of Pharmaceutical Chemistry,Faculty of Pharmacy,Rangsit University,Muang,Pathum Thani 12000,Thailand

bSino-Thai Traditional Medicine Research Center(Cooperation between Rangsit University,Harbin Institute of Technology,Heilongjiang University of Chinese Medicine),Faculty of Pharmacy,Rangsit University,Muang, Pathum Thani 12000,Thailand

cSun Herb Thai Chinese Manufacturing Plant,Faculty of Pharmacy,Rangsit University,Muang,Pathum Thani 12000,Thailand

A R T I C L E I N F O

Article history:

Available online 24 November 2015

Hydrogel flms

Lactic acid

Polyvinyl alcohol

Swelling

Hydrogel flms are the thin-flm formation that can absorb the water or biological fuids shown as hydrated polymer gels.Hydrogel flms have a potential as carriers for bioactive macromolecules,wound dressing,and controlled drug release. Polyvinyl alcohol(PVA)is a biodegradable and biocompatible synthetic polymer which has been widely used in pharmaceutical felds.This work aims to study the swelling behavior of hydrogel flms prepared from PVA and lactic acid(LA)intended to use as drug delivery system.

Five grams of PVA were dissolved in hot water until clear solution and then slowly mixed with 7.5 g of LA solution at room temperature.Subsequently,the mixture was cured in a hot oven at 100°C for different curing times.The hydrogel flms were determined for the swelling behaviors in the solution of chloride salts(10 mmol/L NaCl and KCl),and aqueous solution with various pHs(pH 2,4,7,and 10).The equilibrated swollen hydrogel flms were weighted and calculated as the increasing weight compared to the initial weight of hydrogel flms.The swelling ratio measurement of hydrogel flms was investigated as shown in Fig.1(left).The swelling ratio in saline solutions signifcantly decreased from Na+to K+.This was due to the size of the ion,the large ion is more diffcult than small ion to penetrate into the hydrogel flms[1].This phenomenon can be described by Flory’s equation that has been reported and published elsewhere[2].In addition,when the mixing time and curing time increased,the swelling ratio was clearly decreased.The hydrogel flms might be increased strong and hard flms[3].The swelling behavior of hydrogel flms in different pH solutions showed that the hydrogel flms highly swelled at pH 7.The selected PM8 hydrogel flm was hydrated in distilled water at room temperature and then freezedried.The cross-section morphology by SEM technique is shown in Fig.1(right).Obviously,the hydrogel flm showed a coarse and undulant surface.Thus,the water could easily penetrateinto the hydrogel flm structure.Thus,the hydrogel flms could be easily prepared from PVA and LA,which had good swelling properties and good water absorbency.In conclusion,this research supported the preparation of pharmaceutical formulation for drug delivery systems such as buccal flm and transdermal patches.

Fig.1–Swelling ratio measurement of hydrogel flms(left)and the cross section morphology of PM8 hydrogel flms(right): PM1,2,3 mixed for 30 min,PM4,5,6 mixed time for 60 min,and PM7,8,9 mixed for 90 min with curing time for 120,150, and 180 min,respectively.

Acknowledgement

The authors would like to acknowledge the Faculty of Pharmacy and the Research Institute of Rangsit University(Grant no.36/2557)for fnancial supports.

R E F E R E N C E S

[1]Bao Y,Ma J,Li N.Synthesis and swelling behaviors of sodium carboxymethyl cellulose-g-poly(AA-co-AM-co-AMPS)/MMT superabsorbent hydrogel.Carbohydr Polym 2011;84:76–82.

[2]Lanthong P,Nuisin R,Kiatkamjornwong S.Graft copolymerization,characterization,and degradation of cassava starch-g-acrylamide/itaconic acid superabsorbents. Carbohydr Polym 2006;66:229–245.

[3]Suksaeree J,Luprasong C,Charoenchai L,et al.Swelling–deswelling characterization of modifed poly(vinyl alcohol)-graft-lactic acid hydrogels–based on eco-friendly synthesis method.Bull Health Sci Tech 2014;12:7–12.

*E-mail address:jirapornchai.s@rsu.ac.th.

Peer review under responsibility of Shenyang Pharmaceutical University.

http://dx.doi.org/10.1016/j.ajps.2015.11.107

1818-0876/?2016 Production and hosting by Elsevier B.V.on behalf of Shenyang Pharmaceutical University.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).