Abstract
Objective: Current study focuses on the formulation and characterization of lipophilic and hydrophilic gel formulations of nifedipine to treat anal fissure via anodermal application.
Methods: Lipophilic gels were prepared with Aerosil grades as gelling agents in bulk oils. Polyethylene glycols, hydroxypropyl methylcellulose, and Carbopol® 974P were used as gelling agents in water and propylene glycol for forming hydrophilic gels. The effect of repeated Freeze-Thaw Cycles (FT-C) on microstructures of the gels was investigated by examining viscosity, rheology and textural properties. Aerosil 200 containing lipophilic gels exhibited thixotropic behavior with plastic flow properties and higher viscosities.
Result: Accordingly, their compressibility and adhesiveness increased. FT-C caused notable changes in microstructures and textural properties of the lipophilic gels excluding the formulation containing Aerosil 200-in-isopropyl myristate. Among the hydrophilic gels, the viscosity of Carbopol® 974P gels increased depending on the amount of polymer, triethanolamine and water; these gels featured plastic flow without thixotropic behavior. Their compressibility and adhesiveness were higher than other gel formulations with stable post-FT-C characteristics. The higher flux values of nifedipine were observed from water containing Carbopol® 974P gel.
Conclusion: The results of the stability tests showed that the Carbopol® 974P gel had a longer shelf life than the Aerosil 200-in-isopropyl myristate gel.
Keywords: Nifedipine, anal fissure, anorectal gel, texture analysis, rheology, freeze-thaw cycle.
Graphical Abstract
[http://dx.doi.org/10.1055/s-0035-1570390] [PMID: 26929749]
[http://dx.doi.org/10.1007/s10151-011-0683-7] [PMID: 21538013]
[PMID: 12953727]
[http://dx.doi.org/10.5772/33713]
[http://dx.doi.org/10.1111/j.1365-2036.2006.02990.x] [PMID: 16842451]
[http://dx.doi.org/10.1136/bmj.292.6529.1167] [PMID: 3011180]
[http://dx.doi.org/10.1308/003588407X202137] [PMID: 17688717]
[http://dx.doi.org/10.1007/BF02234624] [PMID: 11535842]
[http://dx.doi.org/10.1007/s10350-004-0693-x] [PMID: 15622590]
[http://dx.doi.org/10.1007/s00384-005-0766-x] [PMID: 16091912]
[http://dx.doi.org/10.1111/j.1572-0241.2007.01203.x] [PMID: 17531031]
[PMID: 21287460]
[http://dx.doi.org/10.1007/BF02236693] [PMID: 10458123]
[http://dx.doi.org/10.1007/BF02236630] [PMID: 11052511]
[http://dx.doi.org/10.1007/s10350-004-6660-8] [PMID: 12794583]
[http://dx.doi.org/10.1007/978-3-540-69419-9_20]
[http://dx.doi.org/10.1023/A:1012091231023] [PMID: 9144730]
[http://dx.doi.org/10.1201/9780824744694.ch8]
[http://dx.doi.org/10.1201/b14194-22]
[http://dx.doi.org/10.1201/9780824743239.ch7]
[http://dx.doi.org/10.1016/j.cocis.2011.05.005]
[http://dx.doi.org/10.1016/j.foodres.2012.05.020]
[http://dx.doi.org/10.1016/j.foostr.2014.07.002]
[http://dx.doi.org/10.3109/03639049209043696]
[http://dx.doi.org/10.1023/B:PHAM.0000033006.11619.07] [PMID: 15290859]
[http://dx.doi.org/10.1023/A:1015853223929] [PMID: 1798677]
[http://dx.doi.org/10.1016/j.ijpharm.2004.06.012] [PMID: 15336387]
[http://dx.doi.org/10.1007/s11095-005-8244-2] [PMID: 16215775]
[http://dx.doi.org/10.1016/S0378-5173(97)00282-2]
[http://dx.doi.org/10.1016/S0378-5173(99)00005-8] [PMID: 10370188]
[http://dx.doi.org/10.1208/s12249-009-9369-0] [PMID: 20077041]
[http://dx.doi.org/10.1016/S0378-5173(98)00110-0]
[http://dx.doi.org/10.1159/000321038]
[http://dx.doi.org/10.1016/S0031-6865(96)00022-2] [PMID: 8921743]
[http://dx.doi.org/10.1161/01.RES.66.5.1449] [PMID: 2335037 ]
[http://dx.doi.org/10.1080/080370598438999] [PMID: 9850436]
[http://dx.doi.org/10.1208/pt060363] [PMID: 16354011]
[http://dx.doi.org/10.2306/scienceasia1513-1874.2006.32.429]
[http://dx.doi.org/10.1002/app.42761]
[http://dx.doi.org/10.1081/DDC-100100358] [PMID: 10738647]
[http://dx.doi.org/10.1080/10717540701829234] [PMID: 18197525]
[http://dx.doi.org/10.3109/10837450.2010.508074] [PMID: 20715905]
[http://dx.doi.org/10.1016/S0378-5173(97)04904-1]