Search

In this study, povidone-iodine (PVP-I) has been formulated as a topical spray to produce a thin film for the controlled release of I2. By means of experimental design, 27 formulations containing glycerol, ethanol, PEG 400, copovidone and HFA 134a as a propellant were prepared. The pH values of all formulations were in the range of 6-7. The viscosity was within the range of 11.9-85.9 mPa s. The surface tensions were 20.3 to 24.6 mN m-1 and the contact angles were between 19.3 and 38.7°. The assays for the iodine contents were within acceptable range (80-120 %). X-ray photoelectron spectroscopy analysis revealed the ionized form of iodine was much higher than the unionized form. The MIC and MBC values of the PVP-I sprays against Staphylococcus aureus, S. epidermidis and Pseudomonas aeruginosa were higher than that of commercial PVP-I solution. The cytotoxicity study confirmed that the PVP-I spray had lower toxic effects on keratinocytes and fibroblasts compared to the commercial PVP-I solution. The formulation containing 59 % ethanol, 18 % copovidone and 12 % PEG 400 showed good antibacterial activity.

Background: Oral inflammatory ulcers are one of the common complaints of patients attending out-patient clinics. Previous in vivo studies had shown that an Aqueous M. citrifolia Fruit Extract (AMFE) possessed anti-inflammatory and ulcer healing activities. Therefore, a standardized topical bioadhesive gel containing AMFE-phytosome was developed and determined for its oral ulcer healing efficacy in a rabbit model., Methods: The AMFE phytosome (AMFE-P) was prepared by a complexation method with the required amount of AMFE: Phosphatidylcholine: Tween 80 to weigh ratio of 2:1:0.2. Poloxamer 407 was used as a gelling agent. The oral ulcer was induced in male New Zealand white rabbits by topical application of acetic acid. Each test compound was applied to the ulcer for 10 days beginning on the second day after the ulcer induction. Complete ulcer healing on the specimen obtained on day 12 was observed histologically using the histological scoring protocol., Results: The optimized gel containing AMFE-P equivalent to AMFE 10%w/w (10%AMFE-P gel) showed the best bioadhesive gel quality, a smooth and homogeneous texture with an optimum viscosity and pH range used in human oral cavity, a good physical and chemical stability and the highest percentage cumulative release of total phenolic and scopoletin content. It was found that a daily application of 10% AMFE-P gel exerted a superior ulcer healing efficacy and a significantly rapid ulcer healing process than a twice daily application of topical gel containing AMFE 10%w/w or chlorhexidine 0.2%., Conclusion: These findings demonstrated that 10% AMFE-P gel has potential as a safe and effective alternative therapeutic agent for oral ulcers., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: An alcohol-free mouthwash of curcuminoids purified from the turmeric ( Curcuma longa Linn.) rhizome was formulated using a cosolvent system, comprising chitosan and polyethylene glycol (PEG) 400, and determined for its efficacy and safety in management of denture stomatitis (DS) in comparison with a chlorhexidine (CHX) mouthwash. Design: A single-center, randomized, controlled parallel-arm trial was conducted. Setting: The study took place at the Faculty of Dentistry, Prince of Songkla University, Hat-Yai, Thailand, between June 2016 and June 2017. Subjects: Participants were 20 years old or older adults of both genders, using removable dentures, and with a confirmed diagnosis of DS from an oral medicine specialist. Interventions: A total of 30 patients were randomly assigned to 3 different interventions, including the chitosan-curcuminoid (CHI-CUR) mouthwash, CHX mouthwash, and a vehicle formulation comprising chitosan and PEG 400. Ten milliliters of each intervention was given to the patient to be used for 30 sec, three times a day at 8 am, 12 pm, and 4 pm, for 2 weeks. Outcome measures: Outcome measures included complete relief of erythematous lesions under the denture and reduction in the number of candida colonies present in the denture-fitting surface. Results: Eight of 10 patients (80%) using the CHI-CUR mouthwash had a complete response after the 2-week treatment course compared with 30% of patients using the CHX mouthwash ( p  < 0.05). Both interventions exerted comparable anticandida efficacy. No oral or systemic adverse events that could possibly be related to the use of mouthwash were documented. Conclusions: The finding indicated that an alcohol-free CHI-CUR mouthwash may serve as a safe and potential topical therapeutic alternative in treating generalized or candida-associated DS.

The purpose of this study was to develop self-microemulsifying formulations of an Andrographis paniculata extract in liquid and pellet forms for an improved oral delivery of andrographolide. The optimized liquid self-microemulsifying drug delivery system (SMEDDS) was composed of A. paniculata extract (11.1%), Capryol 90 (40%), Cremophor RH 40 (40%) and Labrasol (8.9%). This liquid SMEDDS was further adsorbed onto colloidal silicon dioxide and microcrystalline cellulose, and converted to SMEDDS pellets by the extrusion/spheronization technique. The microemulsion droplet sizes of the liquid and pellet formulations after dilution with water were in the range of 23.4 and 30.3 nm. The in vitro release of andrographolide from the liquid SMEDDS and SMEDDS pellets was 97.64% (SD 1.97%) and 97.74% (SD 3.36%) within 15 min, respectively while the release from the initial extract was only 10%. The oral absorption of andrographolide was determined in rabbits. The C(max) value of andrographolide from the A. paniculata extract liquid SMEDDS and SMEDDS pellet formulations (equivalent to 17.5mg/kg of andrographolide) was 6-fold and 5-fold greater than the value from the initial extract in aqueous suspension (equivalent to 35 mg/kg of andrographolide), respectively. In addition, the AUC(0-12h) was increased 15-fold by the liquid SMEDDS and 13-fold by the SMEDDS pellets compared to the extract in aqueous suspension, respectively. The results clearly indicated that the liquid and solid SMEDDS could be effectively used to improve the dissolution and oral bioavailability that would also enable a reduction in the dose of the poorly water soluble A. paniculata extract., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Molecularly imprinted polymers (MIPs) for screening to detect rubber latex allergens (Hev b1) in natural rubber based products were designed as artificial recognition polymeric materials coated onto a quartz crystal microbalance (QCM). The polymers were prepared using a stamp imprinting procedure after mixing optimum amounts of methacrylic acid-vinylpyrrolidone-dihydroxyethylene bisacrylamide and Hev b1 latex allergen proteins, obtained from rubber gloves. QCM measurements showed that the resulting polymer layers after removal of the proteins used in their preparation could incorporate structures and features down to nanometer scale of protein templates into the imprinted polymer much better than a non-specific control polymer under controlled sensor conditions and an optimized polymerization process. This selective polymer but not the non-selective polymer clearly distinguished between the latex allergen Hev b1 and proteins such as lysozyme, ovalbumin and bovine serum albumin, with a selectivity factor of from 2 to 4, and the response of the rubber elongation factors by an astonishing factor of 12. The imprinted cavities recognized specific binding sites and could distinguish among related hevein latex allergenic proteins isolated from fresh natural rubber latex; Hev b1, Hev b2, and Hev b3 with a selectivity factor of from 4 to 6. The different QCM measurements obtained presumably reflected slightly different conformations and affinities to the MIP binding sites. The sensor layers selectively adsorbed Hev b1 within minutes in amounts ranging from 10 to 1500 μg L⁻¹ and with a detection limit of 1 μg L⁻¹. This work has demonstrated that this new sensor provides a fast and reliable response to natural rubber latex protein, even after being extracted from the matrix of rubber gloves., (Copyright © 2010 Elsevier B.V. All rights reserved.)

This study describes the development and characterization of self-microemulsifying drug delivery systems (SMEDDS) in liquid and pellet forms that result in improved solubility, dissolution, and in vivo oral absorption of the poorly water-soluble compound curcumin. Solubility of curcumin was determined in various vehicles, including oils, surfactants and co-surfactants. Pseudo-ternary phase diagrams were constructed to identify the most efficient self-emulsification region. The optimized SMEDDS used for curcumin formulations in liquid and pellet forms contained 70% mixtures of two surfactants: Cremophor EL and Labrasol (1:1), and 30% mixtures of oil: Labrafac PG and Capryol 90 (1:1). The curcumin-SMEDDS in liquid and pellet formulations rapidly formed fine oil-in-water microemulsions, with particle size ranges of 25.8-28.8 nm and 29.6-32.8 nm, respectively. The in vitro rate and extent of release of curcumin from liquid SMEDDS and SMEDDS pellets was about 16-fold higher than that of unformulated curcumin. Plasma concentration-time profiles from pharmacokinetic studies in rats dosed with liquid and pelleted SMEDDS showed 14- and 10-fold increased absorption of curcumin, respectively, compared to the aqueous suspensions of curcumin. Curcumin-SMEDDS liquid and curcumin-SMEDDS pellets were found to be stable up to 6 months under intermediate and accelerated conditions. These studies demonstrate that the new self-microemulsifying systems in liquid and pellet forms are promising strategies for the formulation of poorly soluble lipophilic compounds with low oral bioavailability., (Copyright © 2010 Elsevier B.V. All rights reserved.)

The preventive effect of curcumin, a compound isolated from the rhizome of Curcuma longa, on experimental reflux esophagitis in rats was investigated in order to validate its potential therapeutic use for gastroesophageal reflux disease. Curcumin (20 mg/kg, i.d.), the antioxidative agent dimethyl sulfoxide (DMSO) (1 ml/kg, i.p.) or the proton pump inhibitor lansoprazole (1 mg/kg, i.d.) inhibited the formation of acute acid reflux esophagitis by 52.5, 61.5 and 70.9% respectively. Curcumin alone was not effective in preventing chronic acid reflux esophagitis, but the combination of curcumin and DMSO reduced the mortality rate and the severity of the esophagitis ulcer index to the same extent (56.5%) as did the lansoprazole (53.9%). Intraduodenal administration of curcumin also markedly prevented the formation of acute mixed reflux esophagitis, together with reducing the incidence or the severity of neutrophil infiltration, when compared to a control group. In contrast, lansoprazole tended to increase the severity of all histopathological changes, when compared to either the control or the curcumin-treated group. Aminoguanidine, a specific inducible nitric oxide synthase inhibitor, had no preventive effect against both types of acute reflux esophagitis models, and increased the mortality in the chronic acid reflux esophagitis model. From these results, it is indicated that curcumin can effectively prevent acute reflux esophagitis formation. Although curcumin is less potent than lansoprazole in inhibiting acid reflux esophagitis, it is superior to lansoprazole in inhibiting mixed reflux esophagitis. The antiulcerogenic mechanisms are considered to be closely associated with its antioxidant nature and antiinflammatory property.

A novel technique based on Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to study the transport of benzoic acid ion-pairs/salts in silicone membranes. The benzoic acid ion-pairs were prepared using various counter-ions with different degrees of lipophilicity, e.g. triethylamine (TA), diethylamine (DE), tert-butylamine (t-BA), 2-amino-2-methyl-propanol (AMP), and 2-amino-2-methyl-propanediol (AMPD). Silicone membrane, treated or untreated with propylene glycol (PG), was placed on the surface of a ZnSe crystal and the transport solution was applied to the upper surface of the membrane. A mathematical model, based on Fick's second law describing the build up of permeant concentration at the membrane/crystal interface with time was applied to determine diffusion coefficients. Absorption due to the acid (1700 cm(-1)) or benzoate anion (1555 cm(-1)) was observed at different regions without the interference from PG or silicone membrane. Benzoate anion, a charged species, was observed to permeate the membrane. The permeation of benzoate anion from sodium benzoate and polar ion-pairs of AMP and AMPD was very low in contrast to their high-saturated concentrations in PG as compared to the t-BA ion-pair. This indicated that benzoate anion preferentially permeates the membrane as an ion-pair rather than a single anion; otherwise its permeation should correspond to its concentration in PG instead of the lipophilicity of the ion-pairs. Additionally, the diffusion coefficient values of benzoic acid and benzoate anions through the treated and untreated membranes were not statistically different.

Purpose: Prodrug of non-steroidal anti-inflammatory drugs (NSAIDs) or NSAIDs linked with guaiacol have been reported to suppress gastrointestinal (GI) toxicity or induce GI protective effect. In this study. mefenamic-guaiacol ester was synthesized and its physicochemical properties. stability, and transport across Caco-2 monolayers were investigated., Methods: Synthesis of the ester was carried out using mefenamic acid, guaiacol. N. N'-dimethylaminopyridine, and N,N'dicyclohexylcarbodiimide. The hydrolysis of the ester was investigated in aqueous buffer solutions pH 1-12 as well as in Caco-2 homogenate, human plasma, and porcine liver esterase. Caco-2 cell monolayers were utilized for transport studies. Due to the high lipophilicity of the ester with a calculated logP of 6.15, bovine serum albumin (BSA, 4%) was included in the receiver compartment to obtain a good in vitro-in vivo correlation. Permeation of the ester was assessed with or without the exposure of cells to PMSF, an inhibitor of esterase., Results: The ester was stable at a wide pH range from 1-10. However, it was hydrolyzed by enzymes from porcine liver esterase and Caco-2 homogenate. With the PMSF exposure on the apical (AP) side and in the presence of 4% BSA on the basolateral (BL) side, the transported amount of the ester from AP-to-BL direction was 14.63% after 3 hr with a lag time of 23 min. The Papp for the ester was 4.72 x 10(-6) cm s(-1)., Conclusion: The results from hydrolysis studies indicate that this ester is a prodrug. The Papp value suggests the moderate absorption characteristic of the compound. The accumulation of this highly lipophilic ester in Caco-2 cells is reduced in the presence of BSA.

To demonstrate the potential alternative sources of starch used in tablet formulations, starches from taro (TS) and sweet potato (SPS) tubers were prepared with obtained yields of 11.0 and 9.6%, respectively. Both TS and SPS met USP22-NF17 identification and specifications. Their equilibrium moisture contents and gelatinization temperatures were comparable with those of commercial starch, whereas amylose contents of TS and SPS were 21.38% w/w and 41.76% w/w, respectively. Both were found to possess similar flow characteristics. To evaluate TS and SPS as granulating agents and disintegrants, tablets with controlled compression loads were prepared by incorporating a starch candidate with dibasic calcium phosphate in paste and powders forms, respectively. Tablets were then evaluated based on compressibility, friability, and disintegration. It was found that the binding and disintegrating performance of both TS and SPS was similar to that of commercial cornstarch.

The stability of norfloxacin as extemporaneous suspensions compounded from two brands of film-coated tablets (formulas I and II) was studied. The vehicle consisted of tragacanth, saccharin sodium, sorbitol solution, glycerin, paraben concentrate, peppermint spirit BP, purified water, and syrup USP. The final concentration of norfloxacin in the suspensions was 20 mg/ml. Formulas I and II were chemically stable for 28 days when stored in amber glass bottles at ambient temperature; however, their physical characteristics were different.