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The objective of this study was to develop ritonavir (RTV) nanosuspensions (NSs) by microfluidization method. Particle size (PS) measurements were performed by photon correlation spectroscopy. Amorphous properties of the particles were evaluated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dissolution studies were conducted in fed state simulated intestinal fluid (FeSSIF) medium. The flow cytometry was utilized to determine the lymphocyte sub-groups and immune response of NSs. RTV NSs were obtained with 400-500 nm PS. The crystal properties of RTV remain unchanged. The solubility of NS was enhanced five times. 57% and 18% of RTV were dissolved in FeSSIF medium for NSs and coarse powder. According to immunological studies, the prepared NSs did not significantly alter the ratio of CD4

Purpose The objective of this study was to optimize the Flurbiprofen (FB) nanosuspension (NS) based gel and to investigate the in vitro release, ex vivo permeation, the plasma concentration-time profile and pharmacokinetic parameters. Methods FB-NSs were developed using the wet milling process with the Design of Experiment (DoE) approach. The optimum FB-NS was characterized on the basis of SEM, DSC, XRPD, solubility and permeation studies. The dermal gel was prepared by incorporating FB-NS into HPMC gel. Then the in-vitro release, ex vivo permeation studies were performed, and pharmacokinetic studies were evaluated on rats. Results The particle size, polydispersity index and zeta potential values of optimum NS were determined as 237.7 +/- 6.8 nm, 0.133 +/- 0.030 and - 30.4 +/- 0.7 mV, respectively. By means of the surfactant content and nanosized particles of the nanosuspension, the solubility of FB was increased about 7-fold. The percentage permeated amount of FB from FB-NS gel (8.40%) was also found to be higher than the physical mixture (5.25%) and coarse suspension (reference) (2.08%) gels. The pharmacokinetic studies showed that the C-max of FB-NS gel was 2.5 times higher than the reference gel, while AUC(0-24) was 2.96 times higher. Conclusion FB-NSs were successfully prepared with a wet milling method and optimized with the DoE approach. The optimized FB nanosuspension gel provided better permeation and pharmacokinetic performance compared to FB coarse suspension gel.

Objectives The current study focused on the evaluation of the cytotoxic effect and permeability of ziprasidone hydrochloride monohydrate (ZHM) nanocrystals on Caco-2 cells. Materials and methods ZHM nanocrystals were prepared by the microfluidization method in the presence of polyvinylpyrrolidone as a stabilizer. Particle size (PS), particle size distribution (PDI), and zeta potential (ZP) values were measured in characterization studies. In vitro cytotoxic effects of ZHM nanocrystals were investigated using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Caco-2 transport studies were conducted with formulations of ZHM coarse powder and nanocrystals. Results Nanocrystals were obtained with 400-600 nm PS, 0.1-0.4 PDI, and >20 mV ZP values. The cell viability remained 100% for all sample groups. The permeability value of ZHM nanocrystals through Caco-2 cells increased 2.3-fold in comparison with ZHM coarse powder. Cumulative drug transport also increased at the end of the sampling period. Conclusion Nanocrystal technology helps to increase the permeability of drug particles by increasing the saturation solubility.

Aim: Aim of this study was to develop exendin-4 and exendin-4/chymostatin loaded self-nanoemulsifying drug delivery system (SNEDDS).Methods: Surfactants and co-surfactants were mixed, oil phase con...

The objective of this study was to develop dermal nanosuspension (NS) based gel formulation of etodolac (ETD).Etodolac nanosuspension (ETD-NS) was prepared by wet milling method and dispersed in hydroxypropyl methylcellulose (NS-HPMC) or hydroxyethyl cellulose (NS-HEC) gels. Rheologic and mechanical properties were investigated.The ETD-NS with approximately 190 nm particle size (PS), 0.16 polydispersity index (PDI), and -15 mV zeta potential (ZP) values were obtained. The work of bioadhesion values of NS-HEC and NS-HPMC gels were 0.229 mJ/cmETD-NS based gel formulation is promising for topical delivery of ETD.

The objective of this study was to prepare a stable self-nanoemulsifying formulation of exendin-4, which is an antidiabetic peptide. As exendin-4 is commercially available only in subcutaneous form, several attempts have been made to discover an effective oral formulation. Self-nanoemulsifying drug delivery systems are known to be suitable carriers for the oral administration of peptide drugs. Various ratios of oil, surfactant, and co-surfactant mixtures were used to determine the area in the pseudoternary phase diagram for clear nanoemulsion. The Design of Experiment approach was used for the optimization of the formulation. Blank self-nanoemulsifying formulations containing ethyl oleate as oil phase, Cremophor EL(R), and Labrasol(R) as surfactant, absolute ethanol, and propylene glycol as co-solvent in various proportions were approximately 18-50 nm, 0.08-0.204 and - 3 to - 23 mV in droplet size, polydispersity index, and zeta potential, respectively. When all formulations were compared by statistical analysis, five of them with smaller droplet sizes were selected for further studies. The physical stability test was performed for 1 month at 5 degrees C +/- 3 degrees C and 25 degrees C +/- 2 degrees C/60% RH +/- 5% RH storage conditions. As a result of the characterization and physical stability test results, ethyl oleate: Cremophor EL(R):absolute ethanol (30:52.5:17.5) formulation and four formulations containing ethyl oleate: Cremophor EL(R):Labrasol(R):propylene glycol:absolute ethanol at varying concentrations were considered for peptide encapsulation efficiency. Formulation having the highest encapsulation efficiency of exendin-4 containing ethyl oleate: Cremophor EL(R):Labrasol(R):propylene glycole:absolute ethanol (15:42.5:21.25:15.94:5.31) was selected for in vitro Caco-2 intestinal permeability study. The permeabiliy coefficient was increased by 1.5-folds by exendin-4-loaded self-nanoemulsifying formulation as compared to the exendin-4 solution. It can be concluded that intestinal permeability has been improved by self-nanoemulsifying formulation.

Flurbiprofen (FB) is an analgesic and anti-inflammatory drug, but its low water solubility (BCS Class II) limits its dermal bioavailability. The aim of this study is to develop a FB nanosuspension (NS) based gel and to evaluate its analgesic and anti-inflammatory activities in rats. FB-NS was produced by the wet milling method with Plantacare 2000 (R), as stabilizer. The FB-NS was then incorporated in different carrier gels such as hydroxypropyl methyl cellulose (HPMC), polycarbophil, oleogel, and chitosan. To select the optimum gel type, visual examinations, pH and rheological property measurements, texture profile analysis, in vitro release and ex vivo permeation studies were performed. Following these tests, the analgesic and anti-inflammatory activities of the optimum NS based gel were evaluated using the tail flick and carrageenan-induced paw edema methods consecutively. The NS was successfully prepared with the wet milling method, and the PS, PDI and ZP values were found to be 237.7 +/- 6.8 nm, 0.133 +/- 0.030, and -30.4 +/- 0.7 mV; respectively. Among the NS-based gels, HPMC gel showed more suitable rheological and mechanical properties, also the percentage of permeated FB and the flux value observed for HPMC gel were higher for HPMC than for the other gels. Thus, HPMC gel was selected as a carrier gel for in vivo pharmacodynamics studies. The anti-inflammatory activity of FB-NS HPMC gel was higher than that of the physical mixture gel and that of the coarse suspension gel. Results of our analgesic activity studies showed that, in the 180th min of FB nanosuspension treatment, the latency time was significantly prolonged compared to that of the control group (p

The objective of this study was to prepare a stable self-nanoemulsifying formulation of exendin-4, which is an antidiabetic peptide. As exendin-4 is commercially available only in subcutaneous form, several attempts have been made to discover an effective oral formulation. Self-nanoemulsifying drug delivery systems are known to be suitable carriers for the oral administration of peptide drugs. Various ratios of oil, surfactant, and co-surfactant mixtures were used to determine the area in the pseudoternary phase diagram for clear nanoemulsion. The Design of Experiment approach was used for the optimization of the formulation. Blank self-nanoemulsifying formulations containing ethyl oleate as oil phase, Cremophor EL

Although flurbiprofen (FB), as one of non-steroidal anti-inflammatory drugs, has various pharmacological applications, it shows low dermal bioavailability due to its low water solubility. To overcome this solubility problem, FB nanosuspensions were developed and the effects of stabilizers were investigated with regard to critical quality attributes. While PVP K30 and HPMC 3 cps were used as non-ionic polymeric stabilizer, Tween 80 and Plantacare 2000 (PL) were used as non-ionic surfactants. The influence of these types of stabilizers and their different ratios were tested. The selected formulations according to results of experimental design were also characterized by SEM, FTIR, XRPD, DSC, and the stability studies were performed. According to results of characterization studies, PL was selected as the appropriate stabilizer. The determined nanosuspension stabilized with PL had the nanosized, spherical, and homogenous dispersed particles. There is no polymorphic change on the crystalline state of FB while producing nanosuspension stabilized with PL. It also retained its stability compared with PVP stabilized nanosuspensions for one month. It was concluded that the design of experimental approach is a useful tool to determine the effect of stabilizer on quality attributes of nanosuspensions and to select the optimum type and ratio of stabilizer for obtaining more stable nanosuspensions.

Purpose Etodolac (ETD) is one of the non-steroidal anti-inflammatory drugs which has low aqueous solubility issues. The objective of this study was to develop ETD nanosuspensions to improve its poor aqueous solubility properties while investigating formulation and process parameters of wet media milling method via design of experiment (DoE) approach. Methods The critical formulation parameters (CFP) were selected as ETD amount, stabilizer type and ratio as well as critical process parameters (CPP) which were bead size, milling time and milling speed. The two-factorial-2(3) and The Box-Benkhen Designs were generated to evaluate CFP and CPP, respectively. Particle size (PS), polydispersity index (PDI) and zeta potential (ZP) were analyzed as dependent variables. Characterization, physical stability and solubility studies were performed. Results Optimum nanosuspensions stabilized by PVP K30 and Poloxamer 188 showed 188.5 +/- 1.6 and 279.3 +/- 6.1 nm of PS, 0.161 +/- 0.049 and 0.345 +/- 0.007 PDI, 14.8 +/- 0.3 and 16.5 +/- 0.4 mV of ZP values, respectively. The thermal properties of ETD did not change after milling and lyophilization process regarding to DSC analysis. Also, the crystalline state of ETD was preserved. The morphology of particle was smooth and spherical on SEM. The dry-nanosuspensions stayed physically stable for six months at room temperature. The solubility of nanosuspensions increased up to 13.0-fold in comparison with micronized ETD. Conclusions In conclusion, it is found that the poor solubility issue of ETD can be solved by nanosuspension. DoE approach provided benefits such as reducing number of experiments, saving time and improving final product quality by using wet media milling.

Several typos occurred during the production process and captions were misplaced. The corrected captions for Picture 1, Fig. 6-9 are below.

The objective of the current study was to develop ziprasidone hydrochloride monohydrate (ZHM) nanocrystal-based orally dispersible tablet (ODT) formulations. Design of experiment approach was used to develop ODTs. The tablets were compressed using direct compression method and characterized with quality control tests. In vitro dissolution studies and Caco-2 cell permeability tests were executed. The hardness and friability values of nanocrystal-based ODTs were found 31.2 N and 1.05%, respectively. The disintegration time was below 10 s. Dissolution profile in pH 7.4 phosphate buffer showed that nanocrystal-based ODTs and commercial product were dissolved in 120 min 58.98% and 16%, respectively. In pH 7.4 phosphate buffer with SLS, sample groups dissolved above 85% at the end of the study. Permeability value and cumulative ZHM amount on the cells were improved with nanocrystals. In conclusion, the novel formulation of ZHM nanocrystal-based ODTs was successfully developed for alternative dosage form.

Background and Aims: Poor aqueous solubility limits drug absorption through intestinal mucosa. Nanosuspensions with nanometer range particle size provides enhanced aqueous solubility and hence permeability. The objective of this study was to investigate the cytotoxicity and in vitro cell permeability through human adenocarcinoma (Caco-2) cells of ritonavir (RTV) nanosuspensions. Methods: The Microfluidization method was used to prepare nanosuspensions. Particle size (PS), polydispersity index (PI) and zeta potential (ZP) values were measured as characterization. MTT test was applied to evaluate the cytotoxic effect. Caco-2 cell lines were used for transport studies with RTV coarse powder, physical mixtures and nanosuspension. Results: Approximately 600 nm PS, 0.4 PDI and 22 mV ZP values were observed for nanosuspensions. The sample groups showed no cytotoxicity on the cell lines in any RTV concentration. However, significant cytotoxic effect was determined in groups with high amounts of sodium dodecyl sulfate. The transported RTV in nanosuspension formulation enhanced by 5.3- fold and 1.5-fold in comparison with RTV coarse powder and physical mixture, respectively. Rate of the transportation and also the amount of the transported RTV were improved with nanosuspension formulation. Conclusion: Particle size reduction of RTV into nanometer size and preparing nanosuspension system was found effective to obtain enhanced cell permeability.

© 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group.Amphotericin B (AmB) is a very potent antibiotic which still remains as the gold standard for the treatment of systemic fungal infections. AmB is a member of Biopharmaceutical Classification System Class IV, mainly characterized by its poor solubility and low permeability. In this study, AmB/AmB-α cyclodextrin complex double loaded liposomes (DLLs) were developed using the design of experiments (DoE®) approach to optimize/determine the effects of lipid composition and other parameters on final product properties such as encapsulation efficacy, particle size, polydispersity index, and zeta potential. Experimental design 24 was used for optimization of these properties in which four factors were studied in two levels. DLLs showed much higher physical stability than liposomes loaded only with free AmB by the means of particle size, zeta potential and encapsulation efficiency, in addition exhibited sustained release of AmB over 72 h (26.7%) with faster onset time. On the other hand, fourfold improved antimicrobial efficiency, minimum inhibitory concentration (0.125 µg/ml), and minimum fungicidal concentration (0.5 µg/ml) was determined by DLLs against C. albicans compared to Ambisome®. Dose dependent effects of the DLLs were investigated by cytotoxicity studies on Vero and L-929 cells. No significant cytotoxicity observed for AmB/AmB–αCD complex DLLs and Ambisome at tested concentrations while free AmB caused severe cytotoxicity. Lastly the developed DLLs did not cause an increase in NGAL (an early biomarker for acute kidney toxicity) levels for both Vero and HK-2 cell lines compared to free AmB.

Flurbiprofen (FB) is an effective nonsteroidal anti-inflammatory and BCS class II drug and its poor solubility plays a critical role in limiting its bioavailability. Nanosuspensions can be defined as nanosized colloidal dispersions of drug particles stabilized with stabilizers. The solubility of poor soluble drugs can be increased thanks to their small size and large surface area. The aim of this study is to optimize FB nanosuspensions. The formulations were stabilized with Plantacare 2000(?) as a surfactant using a combination of High Speed Homogenization (HSH) and High Pressure Homogenization techniques (HPH). We also investigated the effects of the critical process parameters (CPPs) of these techniques (homogenization speed & time for HSH and homogenization pressure & cycle for HPH) on three critical quality attributes of nanosuspensions, being the particle size (PS), polydispersity index (PDI) and zeta potential (ZP). After the optimization of HSH, the macrosuspension was transferred to a high pressure homogenizer. After producing FB nanosuspensions by the HPH technique, seven processes which comprise different homogenization pressures, or combinations and different cycles, were applied. Due to the combination of HSH and HPH techniques and the optimization of CPPs, an optimum formulation for a dermal application was found using a 3(3) full factorial design with these process parameters, and characterization studies were also performed.

The main objective of this study was to evaluate the pharmacokinetics of ritonavir (RTV) nanosuspension in rats in both fed and fasted state in comparison with coarse powder, physical mixture and commercial product (Norvir®). The point to point relation model was generated between the results of in vitro dissolution and in vivo pharmacokinetic studies. The oral RTV nanosuspension was prepared with microfluidization method. Nanosuspension was obtained with 540–550 nm of particle size, 0.1–0.4 of particle size distribution and about −20 mV of zeta potential values. According to in vivo pharmacokinetic studies in rats, Cmax and AUC0−t values in nanosuspension displayed an 8.9- and 12.5-fold increase compared to the coarse powder, and a 1.9- and 2.1-fold increase compared to the commercial product, respectively in the fed group. The point to point relation model showed that the correlation model was significant. It is concluded that nanosuspension is a promising drug delivery system to enhance oral bioavailability of ritonavir.

Flurbiprofen (FB) is the one of the non-steroidal anti-inflammatory drugs (NSAIDs) which has low water solubility and dissolution. Nanosuspensions are promising drug delivery systems consisting pure drug particles to overcome poor water solubility issues. Recently, design of experiment (DoE) approaches have often been used to develop new formulations include nanosuspensions. The main objective of this study was to prepare FB nanosuspensions in existence of Plantacare 2000 (PL) as stabilizer using DoE approach to evaluate the critical formulation attributes (CFAs) and critical process parameters (CPPs). Particle size, particle size distribution and zeta potential values were selected as dependent variables and FB%, FB: PL and homogenization cycles were independent variables. Both 23 and 33 factorial designs were used to achieve optimum nanosuspension formulation. The final nanosuspension was freeze-dried and then crystalline state, morphological and thermal properties were investigated using X-ray diffraction, scanning electron microscopy and differential scanning calorimetry, respectively. The saturation solubility studies of nanosuspensions were conducted in comparison with the coarse powder and the physical mixture. The in vitro permeation of nanosuspension and FB solution were determined through dialysis membrane and rat skin. The particle size, polydispersity index and zeta potential values were found to range 665 nm–700 nm, 0.200–0.300 and approximately −30 mV, respectively. Nanosuspensions were obtained with spherical shape and no polymorphic or crystalline state change were observed. The saturation solubility of FB was 5.3 fold increased in nanosuspension formulation. Permeability of FB nanosuspension was higher than FB solution in rat skin. It was concluded that the DoE approach is a useful tool to prepare FB nanosuspensions and nanosuspensions benefit to improve water solubility and dermal permeation of Biopharmaceutical Classification System (BCS) Class II drugs.

Nasal delivery is an emerging strategy to prevent both local and systemic diseases. The aim of this study was to develop a promising and innovative therapeutic system for the nasal delivery system of liposomes. Ovalbumin(OVA) was used as a model compound in this study. For this purpose we have developed OVA containing gel formulations using chitosan(2% w/v) and Carbopol® 974P(0.25% w/v). The developed gels have appropriate pH and viscosity for mucosal administration. We have also developed OVA containing liposome formulation for nasal administration. The developed liposomes have negative zeta potential(-5.33 mV ± 2.019), 200-250 nm particle size and 73% entrapment efficiency. To improve the mucosal retention time, liposome was dispersed in chitosan gel(lipogel). It was shown that developed formulations do not show cell toxicity, by cell viability near 100% on Calu-3 cells which is a model cell line of the respiratory mucosa. Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) results of the formulations also showed that the antigen OVA maintained its integrity except liposome in chitosan gel formulation. We have also evaluated mucoadhesive and mechanical properties of the formulations on sheep nasal mucosa. Results from this study indicate that carbopol gel and lipogel formulations may be effective as nasal delivery systems.

Nowadays pharmaceutical industries and regulatory authorities suggest new approaches such as Quality by Design principles to reduce experiments of formulation studies, improve product quality, save cost and time. SeDeM Expert System is a predictive approach for the preformulation studies and it provides information about suitability of API for direct compression by evaluating 12 parameters. The system also allows selecting appropriate excipients by determining same parameters to improve compressibility of API. The objective of this study was to develop direct compressed memantine orally disintegrating tablets using SeDeM Expert System. Memantine was found to have poor flow and compressibility properties. Three different direct compressibility and super disintegrating agents (Ludiflash((R)), Ludipress((R)) and Parteck((R))) were used to improve compressibility of memantine and according to SeDeM diagrams, Parteck((R)) was selected for final formulation. Memantine direct compressed tablets showed proper friability, hardness and thickness. The disintegration time of the tables were found below 15s which was suitable for ODTs. It was found that SeDeM Expert System was easy to use and application of this method provided to develop memantine direct compressed ODT formulation was successful.

The aim of this study was to develop and characterize rh-IL-2 loaded chitosan-based nanogels for the healing of wound incision in rats. Nanogels were prepared using chitosan and bovine serum albumin (BSA) by ionic gelation method and high temperature application, respectively. Particle size, zeta potential, and polydispersity index were measured for characterization of nanogels. The morphology of nanogels was examined by using SEM and AFM. The IL-2 loading capacity of nanogels was determined using ELISA method. In vitro release of IL-2 from nanogels was performed using Franz diffusion cells. Artificial neural network (ANN) models were developed using selected input parameters (stirring rate, chitosan%, BSA%, TPP%) where particle size was an output parameter for IL-2 free nanogels. Wound healing effect of IL-2 loaded chitosan-TPP nanogel was evaluated by determining the malondialdehyde (MDA) and glutathione (GSH) levels of wound tissues in rats. The particle size of IL-2 loaded chitosan-TPP nanogels was found to be larger than that of IL-2 loaded BSA-based chitosan nanogels. Drug loading capacity of nanogels was found 100% +/- 0.010 for both nanogels. IL-2 was released slowly after the initial burst effect. According to SEM and AFM imaging, BSA-chitosan nanogel particles were of nanometer size and presented a swelling tendency, and chitosan-TPP nanogel particles were found to be spherical and homogenously dispersed. IL-2 loaded chitosan-TPP nanogel was found suitable for improving wound healing because it decreased the MDA levels and increased the GSH levels wound tissues comparing to control group.

Objective: This study was designed to investigate the effects of aqueous or Microemulsion solution containing Transforming Growth factors-alpha (TGF-a) and/or administration of aprotinin on healing rate of duodenal ulcer induced by acetylsalicylic acid, and to examine the relationships between oxidative processes and TGF-a formulation during duodenal ulcer healing by measuring malondialdehyde, glutathione and total nitric oxide levels.

The aim of this study was to prepare a topical water-in-oil type microemulsion containing metronidazole and to compare its effectiveness with a commercial gel product in the treatment of rosacea. A pseudo-ternary phase diagram (K-m=2: 1) was constructed using lecithin/butanol/isopropyl myristate/water. The microemulsion was chosen from the microemulsion region in the phase diagram. The formulation was a water-in-oil type microemulsion (droplet size: 11.6 nm, viscosity: 457.3 mPa.s, conductivity: 1.5 mu s/cm, turbidity: 6.89NTU) and the addition of the metronidazole did not alter the properties of the system. The release experiment showed that the release rate of metronidazole from the commercial gel product was higher than that of the microemulsion. Stability experiments showed that the metronidazole microemulsion remained stable for at least 6 months; none of the characteristic properties of the microemulsion had changed, the system retained its clarity and there was no sign that crystallization of metronidazole has occurred. Microemulsion was compared to a gel product in a randomized, double-blind, baseline-controlled, split-face clinical trial for the treatment of patients. After the 6-week treatment period there was a statistically significant difference in reduction of the main symptoms of rosacea. Of the patients treated with the microemulsion, 17% experienced complete relief from inflammatory lesions, and 50% from erythema. The microemulsion resulted in complete relief in 38% of the patients with telangiectasia while the commercial product did not provide any relief of telangiectasia symptoms. In conclusion, the microemulsion containing metronidazole was found to be more effective in reducing the symptoms of rosacea compared to the commercial gel product.

This study aimed to prepare a water-in-oil microemulsion formulation of alendronate. Pseudo-ternary phase diagrams were constructed by using different oils and co-surfactants. The final formulation was decided to be prepared with Captex 200 (R), lecithin, propylene glycol and bidistilled water. Rheological behaviour, phase stability and type of the microemulsion formulation were investigated by Brookfield viscosimeter, centrifugation test and dye method, consequently. Phase behaviour of the formulation was found to be Newtonian. No precipitation was observed in the stressed conditions and formulation was W/O. The physical characterization of the formulation (physical appearance, viscosity, refractive index, conductivity, density and turbidity) was investigated at 4 degrees C and 25 degrees C during 6 months while droplet size was investigated for 3 months. Droplet size of the formulation was between 224-280 nm while viscosity was between 89.9-99.5 mPa.S. The release of alendronate from the microemulsion formulation was examined by dialysis method and found to be 97.2% at the end of 7 h. None of the parameters except refractive index changed significantly during the determined periods. This study succeeded in preparing a stable microemulsion formulation of alendronate.

Various studies have shown that chitosan is effective in promoting wound healing. In this study, we aimed to develop an effective chitosan gel formulation containing epidermal growth factor (EGF), and to determine the effect on healing of second-degree burn wounds in rats. Ten micrograms per millilitre EGF in 2% chitosan gel was prepared. In an in vitro study to investigate release of EGF from the formulations, the release rate was 97.3% after 24 h. In in vivo studies, animals were divided into six groups as follows: silver sulfadiazine [Silverdin(R) cream (SIL)], chitosan gel with and without EGF (EJ, J), EGF solution (ES) and untreated control groups [unburned (S) and untreated (Y) rats] applied groups, respectively. A uniform deep second-degree burn of the backskin was performed with water heated to 94 +/- 1 degrees C during a 15-s exposure. The EGF formulations were repeatedly applied on the burned areas with a dose of 0.160 mu g/cm(2) for 14 days (one application per day). Healing of the wounds was evaluated immunohistochemically, histochemically and histologically on the tissue samples. When the results were evaluated immunohistochemically, there were significant increases in cell proliferation observed in the EGF containing gel applied group (p

The objective of our study was to prepare and characterize a stable microemulsion formulation for oral administration of a peptide, e. g., rh-insulin. The microemulsions were prepared using Labrafil M 1944 CS, Phospholipon 90G (lecithin), absolute alcohol, and bidistilled water. Commercially available soybean lecithins (namely, Phospholipon 80, phosphatidylcholine purity 76 +/- 3%, and Phospholipon 90G, phosphatidylcholine purity 93 +/- 3%) were used in the study. The results showed that the phase diagram obtained using a low purity lecithin was not similar to that obtained with a high purity lecithin. We observed that the microemulsion area was wider at the phase diagram obtained with the higher purity lecithin. We found that the extent of the microemulsion region depended upon both the purity of the lecithin and the surfactant/co-surfactant (s/co-s) mixing ratios (K-m). The rheological studies showed that microemulsions followed a Newtonian behavior. Such physical characteristics as viscosity, turbidity, density, conductivity, refractive index, droplet size, physical appearance, and phase separation of the microemulsion were measured at different temperatures (4 degrees C, 25 degrees C, and 40 degrees C) during 6 months. The results indicated that the physical characteristics of the developed microemulsions did not change under different storage temperatures (p > 0.05).

Transforming growth factor (TGF) alpha accelerates wound healing, especially in gastric ulcers. Transforming growth factor alpha can be affected by acid and pepsin in the gastric juice. Oxidative stress also plays a role in the formation of gastric lesions. This study was designed (1) to investigate the effects of microemulsion dosage form on the healing of gastric ulcers, and (2) to determine the relationship between oxidative mechanisms and TGF-alpha during ulcer healing.Gastric ulcers were induced in Wistar rats (male, 200 +/- 25 g), by 150 mg/kg acidified aspirin application. The animals were divided into five groups consisting of 7-11 animals. The rats were killed after ulcer induction with aspirin (acute ulcer), or 2 days after ulcer induction (chronic ulcer), or after the daily application of microemulsion and TGF-alpha for 2 days. The ulcer area was measured planimetrically. Thiobarbituric acid reactive substance, glutathione, and gastric mucus levels of tissues were measured by spectrophotometric methods. The total nitric oxide level was measured by a VCl3/Griess assay. Statistical comparisons were made by an analysis of variance and the Mann-Whitney U-test.The ulcer area and malondialdehyde level of gastric tissue both decreased and the glutathione level increased to intact gastric tissue levels, while the mucus and total nitric oxide levels increased significantly after the application of intragastric TGF-alpha.These findings suggest that TGF-alpha accelerates the healing process after aspirin-induced gastric injury, and a relationship was observed between this application and the oxidative reactions.

The present study was designed to investigate the effects of microemulsion and aqueous solution containing transforming growth factor alpha (TGF-alpha) and/or aprotinin administered intragastrically (i.g.) on healing of acute gastric ulcers induced by acetylsalicylic acid (ASA). The microemulsion was prepared by modification of the microemulsion formulation described in our previous study. Actue gastric lesions were induced by the application of ASA (150 mg/kg in 1.5 ml of 0.2 N HCl i.g.). TGF-alpha in solution or microemulsion formulations were administered at a dose of 10 mug/kg per 24 h i.g. for 2 days. The effects of TGF-alpha on the healing was evaluated with the measurement of ulcer score, basal gastric acid secretion, total protein content of gastric fluid, gastric mucus level and histological analysis. The results indicated that the highest decrease in ulcer area was observed in group treated with microemulsion containing TGF-alpha plus aprotinin (TA-ME). TGF-alpha in microemulsion formulation was more effective than TGF-alpha in solution formulation in the increase of gastric mucus secretion, in the decrease of gastric acid secretions and ulcer scores. Histological evaluation of the gastric mucosa samples revealed that, best recovery was obtained in the TA-ME treated group. (C) 2004 Elsevier B.V. All rights reserved.

Purpose We investigated the role of epidermal growth factor (EGF) microemulsion (ME) formulation on stress ulcer healing and the levels of gastric mucosal malondialdehyde (MDA) and glutathione (GSH). Methods Forty-eight female Wistar rats were divided into five groups according to the treatments given. Ten rats were given intragastric (i.g.) serum physiologic (SP) for 7 days; ten rats were given i.g. ME for 7 days; ten rats were given i.g. EGF in SP 6 microg/kg per day for 7 days; ten rats were given i.g. ME + EGF (Sigma E-7755) 6 microg/kg per day for 7 days; and eight rats were exposed to cold and immobilization stress or no stress (NS), and not given any treatment, as controls. The mean ulcerated area, and the MDA and GSH levels of the gastric mucosa were measured. Results The mean ulcerated area of the ME+EGF treatment group was significantly less than that of the ME- and EGF-treated groups and the control groups. The gastric MDA levels were also found to be significantly lower in the ME+EGF treated group than in the ME-treated group or the control groups. However, there were no significant changes in the gastric GSH levels among all the groups. The gastric MDA levels were positively correlated with the ulcerated area. Conclusion The ME formulation of EGF at the dose given in this study was more effective than EGF alone on the healing of stress ulceration of the gastric mucosa.

The process of wound healing begins immediately following surface lesions or just after exposure to radiation, chemical agents or extreme temperatures. Taurine (2-aminoethane sulfonic acid), an amino acid containing sulfur, is found in almost all tissues in mammals, playing various important physio-logical roles in each organ. Taurine exhibits an antioxidant effect and is also known to have effects on cell proliferation, inflammation and collagenogenesis. Many antioxidants have been used to eliminate the negative effects of oxygen free radicals on wound healing. The objective of the present study was to examine the wound healing effect in mice of taurine-chitosan gel, which releases taurine slowly over a long time period. Fifty mM of taurine in 1.5% chitosan polymer (TAU-GEL) and 1.5% chitosan polymer (CHI-GEL) were applied to full thickness skin wounds of mice once a day for seven days. After seven days of treatment, lipid peroxide formation-malondialdehyde (MDA) and hydroxyproline (HPX) levels and the tensile strength of wound tissues were measured. All results were compared with those of the untreated control group (CONT). The structural alterations in the skin layers were also histologically investigated. It was found that locally administered TAU-GEL form significantly increased wound tensile strength by decreasing the MDA and increasing HPX levels. These results were supported by histological findings. All observations suggest that taurine gel may be effective in wound healing.

Biodegradable microspheres containing salbutamol sulphate were prepared using water-in-oil-in-water (w/o/w) emulsion technique. Biodegradable polymers of two different molecular weights were used: PLGA 50/50 and PLGA 75/25. In the preparation of the formulations, we used 2(3) factorial design based on three independent variables which are drug loading, amount of gelatin and concentration of PVA. The dependent variables are particle size of the microspheres and entrapment ratio %. The in-vitro release of PLGA microspheres was studied in buffer solution of pH 7.4 at 37 degrees C. a biphasic release behavior of salbutamol sulphate from microspheres was observed. Initially, a burst effect and then slow release was observed. It was found that the biodegradable microspheres of salbutamol sulphate were prepared with PLGA 75/25 by w/o/w emulsion technique obtained extended release obtained for 8 h. PVA concentration was effective on the particle size of microspheres prepared with PLGA 75/25 (p < 0.05).

Microspheres of salbutamol sulphate (SS) with poly(lactic acid-co-glycolic acid) (PLGA 85115) were prepared by the modified solvent evaporation method using a double emulsion. In the preparation of the formulations, we used a 2 3 factorial design based on three independent variables: drug loading, amount of gelatin and concentration of PVA. The dependent variables are particle size of the microspheres and entrapment ratio % in the microspheres. The effect of the three independent variables on the particle size and entrapment ratio % were evaluated with analysis of variance and response surface graphs. The in vitro release studies were carried out by shaking in isotonic phosphate buffer solution, pH 7.4. The particle sizes of microspheres were determined by infrared particle size apparatus (IPS). The interaction between PLGA and drug was investigated by DSC and FT-IR analysis. Extended release was obtained for 96 h with F8 formulation microspheres. The best release profile (F8 formulation) fitted the dissolution model proposed by Baker and Lonsdale. In vitro degradation of the best formulation was investigated using scanning electron microscopy. The pore size increased with time and then degraded becoming empty holes.

Platelet-derived growth factor (PDGF), an important stimulant, plays a role in almost all stages of wound healing process. In various studies, it has been shown that PDGF has healing effects in this process. In the present study, we especially focused on investigating the effects of exogenous PDGF administration on oxidative events during cutaneous wound healing process. Experiments were performed on 42 female Wistar-albino rats. Animals were divided into four groups: control, untreated, chitosan-treated and chitosan + PDGF-treated. Two uniform full-thickness excisional skin wounds were made under anesthesia in all animals except control group. In the chitosan + PDGF-treated groups, the wounds were treated topically with a single daily dose PDGF-BB (7 ng/ml) after wounding. In the chitosan-treated groups, the wounds were treated topically with equal amount of blank chitosan gel. After that, on the 3th and 7th days of wound healing, the animals were killed. Thiobarbituric acid-reactive substances (TBARS), nitric oxide (NOx), ascorbic acid (AA), glutathione (GSH) levels and superoxide dismutase (SOD) activity were measured spectrophotometrically in the wound tissues. PDGF significantly increased TBARS levels in early phase of wound healing. In contrast, it significantly decreased TBARS levels in later phase of healing. In the chitosan + PDGF-treated group, NOx levels decreased on days 3 and 7 when compared with the chitosan-treated groups. Non-enzymatic antioxidant levels were increased by PDGF administration and this may have contributed to increase in wound tissue antioxidant capacity. In the light of these findings, PDGF supplementation may have altering effects on oxidative events depending on the time in wound healing process.

The aim of the present study is to develop microemulsion and liposome carrier systems for oral administration of transforming growth factor alpha (TGF-alpha) and to investigate the effects of these carrier systems on the gastrointestinal efficiency in rats. Microemulsion (w/o) and liposomes (MLV) were developed and characterised. The carrier systems were administered intragastrically by gastric cannula to male Wistar rats. The highest reduction in the basal acid secretion was observed in the microemulsion containing TGF-alpha and aprotinin group (TAME). The gastric mucus secretion in microemulsion containing TGF-alpha (TME) and TAME treatment groups increased significantly compared to the other groups. TGF-alpha levels in both stomach and duodenum were significantly increased in the TAME group. As a result, it was determined through confocal laser scanning microscope (CLSM) studies that exogenous-applied TGF-alpha attached to endogenous EGF receptors. The microemulsion formulation was found to be a more suitable carrier system for oral administration of TGF-alpha.

The objective of this study is to develop a chitosan gel formulation containing liposomes loaded with epidermal growth factor (EGF) and to evaluate their effects on the healing of second-degree burn wounds in rats by immunohistochemical, histochemical and histological methods. EGF-containing multilamellar liposomes which were carried in chitosan gel, EGF gel and EGF-loaded liposome formulations were prepared. The in vivo experiments were performed on female Sprague Dawley rats. Second-degree standard burn wounds were formed on rats and liposomes containing 10 mu g/ml EGF in 2% chitosan gel, EGF-chitosan gel and EGF-loaded liposome formulations were applied daily to the burn wounds and biopsies were taken at the 3rd, 7th and 14th day of the treatment. When the results were evaluated immunohistochemically, there were significant increases in cell proliferation observed in the EGF-containing liposome in chitosan gel (ELJ) formulation applied group ( P < 0.001). The histochemical results showed that the epithelisation rate in the ELJ group was the highest compared with the other group results (P < 0.001). The histological results indicated and supported these findings and faster epithelisation was observed in the ELJ group compared with the other groups.

It was aimed to develop liposome formulations containing epidermal growth factor (EGF) and to investigate the healing effects of these formulations on second-degree burn wounds in rats. Multilamellar type liposomes containing EGF were prepared by film formation method. In vitro releases of EGF from liposome formulations were determined using spectrofluorometer. Second-degree standard burn wounds were formed on rats and liposome formulations containing 10 mu g/ml, EGF (ELP group), EGF solution (ES group), liposome without containing EGF (LP group), and Silverdine (R) ointment (SIL group) were applied daily. Untreated control groups [unburned (S) and untreated (Y) rats] were also evaluated. Biopsies were taken at the 3rd, 7th, and 14th day of the treatment from the wounds and histological observations were performed under transmission electron microscope. Bromodeoxyuridine (BrdU) staining technique was used for immunohistochemical analysis. After trichrome stainings, the thicknesses of the epidermis and the areas of the fibroblast nucleus were measured using a light microscope and Vision Screening Analysis Program. It was observed that the healing in the ELP group was the fastest among all groups (p < 0.05) at the 14th day of therapy. The healing effect in order from highest to lowest efficacy was found to be ELP>SIL>ES groups, respectively, at the 14th day. All results indicated that the EGF-liposome formulation is effective and can be used for the treatment of burn wounds. (c) 2007 Wiley Periodicals, Inc.

The final aim/target of Pharmaceutical Sciences is to design successful dosage forms for effective therapy, considering individual patient needs and compliance. Development of new drug entities, particularly using peptides and proteins, is growing in importance and attracting increased interest, as they are specifically effective at a comparably low dose. These very potent and specific peptides and proteins can now be produced in large quantities due to increased knowledge and advancements in biotechnological and pharmaceutical applications. A number of peptide and protein products are now available on the market, and numerous studies investigating them have been published in the literature. Although many peptide/protein like products are generally designed for parenteral administration, some other noninvasive routes have also been used. For example, desmopressin is delivered nasally and deoxyribonuclease by inhalation. Although peptides and proteins are generally orally inactive, cyclosporine is an exception. In order to design and develop long-acting, more effective peptide/protein drugs, the controlled release mechanisms and effective parameters need to be understood and clarified. Therefore, we review herein various peptide/protein delivery systems, including biodegradable and nondegradable microspheres, microcapsules, nanocapsules, injectable implants, diffusion-controlled hydrogels and other hydrophilic systems, microemulsions and multiple emulsions, and the use of iontophoresis or electroporation, and discuss the results of recent researches.

The effects of intragastric (i.g.) administration of microemulsion formulation of epidermal growth factor (EGF) on the healing of acute gastric ulcers induced by cold-restraint stress in rats was studied and compared with intraperitoneal (i.p.) administration of solutions. In the microemulsion formulation (W/O), labrafil M 1944 CS was the oil phase. Arlacel 186 and Brij 35 were used as the surfactants. Absolute alcohol and distilled water were used as the co-surfactant and the aqueous phase, respectively. Acute gastric lesions were induced by cold-restraint stress for 4 h in the refrigerator (4.0+/-0.5 degreesC). EGF was administered at a dose of 6 mug/kg per day intraperitoneally and intraperitoneally for 7 days. Basal gastric acid secretion (muequiv. H+/30 min), ulcer score (mm(2)) and tissue mucus levels (mug/g tissue) were measured. Basal gastric secretion was significantly reduced after the administration of EGF microemulsion (ME+EGF) (P0.05). The results indicate that the highest reduction in the basal acid secretion was seen after the administration of a microemulsion of EGF formulation. The mean ulcer score was reduced by i.g treatment with the microemulsion dosage form of EGF in 7 days from 15.9+/-1.4 to 1.16+/-0.45 mm(2) and was almost completely healed in four of the animals. The results demonstrate that the ulcer score was significantly reduced in i.p. (IPEGF) solution (P0.05). (C) 2002 Elsevier Science B.V. All rights reserved.

Epidermal growth factor (EGF) and zinc promote re-epithelization and reparative tissue strength by enhancing deposition of collagen at the site of the wound. In this study two EGF dosage forms were chosen to assess the effect of zinc levels on wound healing and for comparison with wound tear strengths. A solution of EGF in 0.9% w/v NaCl and an EGF gel in 0.2% Carbopol 940 polymer (5 μL) were applied to full-thickness skin wounds of mice twice a day for 7 and 15 days. Wound zinc levels were higher on day 7 than on day 15, especially in wounds treated with EGF. The wound zinc levels of the gel + EGF group on day 15 were similar to those of normal control skin. These results imply that there is a close connection, but no direct relationship, between EGF application in both dosage forms and wound zinc levels during healing.

Over the past few years, much attention has been paid to potential pharmaceutical uses of microemulsions as novel drug delivery systems. Microemulsions are defined as multicomponent systems consisting a unique ratio of component including a lipophilic phase, a hydrophilic phase, a surfactant and a co-surfactant1. Main characteristics of this system are low viscosity, isotropicity, thermodynamically stability2 and droplet diameter less than 100 nm3. Such systems are formed spontaneously3,4. The use of microemulsions as possible therapeutic systems is interesting for two main reasons: a) controlled drug release5, b) increased systemic and topical absorption of drugs4,6,7.

The local treatment effects of EGF forms on alkali burned mice corneal wounds were identified. The corneal wounds were induced by 0.5 M NaOH solution on the corneal surfaces of the mice. The local epidermal growth factor solutions (100 ng/ml) and gel form in 0.2 per cent w w carbopol 940 (100 ng/ml) were dropped in 5 μl aliquots into the eye twice a day. The corneal wounds were measured for 15 days at 7-day intervals and examined histologically at the end of 15th day of the experimental period. The results indicated that topical epidermal growth factor treatment in solution improved the healing of alkali burned corneal wounds when compared with epidermal growth factor delivered in a polymer system.

The purpose of the present study was to investigate the interaction of naproxen (NAP) with beta-cyclodextrin (beta-CD) in ground mixtures. The effects of grinding on the physicochemical properties of NAP were studied by means of IR spectroscopy and X-ray diffraction analysis. Ground mixtures of NAP with beta-CD and microcrystalline cellulose (MCC) were prepared by grinding a ceramic ball mill. The dissolution rate of NAP from the ground mixtures was significantly greater than that from physical mixtures and intact NAP powder. The ground mixture with beta-CD showed the fastest dissolution profile. These results indicate that beta-CD can enhance the dissolution rate of NAP.

The effect of topically administered epidermal growth factor (EGF) dosage forms was investigated on skin wound healing in mice. Two EGF dosage forms were prepared containing 100 ng mL−1 EGF. The solution dosage form was prepared in 0·9% w/v NaCl. A bioadhesive gel form was prepared in 0·2% Carbopol 940 polymer. The two dosage forms were applied on the skin incision wounds of mice at the rate of 5 μL twice a day for 7 and 15 days. The wound tear strength was tested for skin wound healing at the 7th and 15th days of treatment and compared with controls. The results indicate that the wound tear strength of mice were significantly higher at the 15th day of treatment in the gel-treated group compared with the solution-treated mice and controls (P < 0·001).

The aim of this study was to increase the solubility and dissolution rate of naproxen (NAP) by inclusion complex formation with β-cyclodextrin (β-CD). The solubility of NAP with β-CD in aqueous solution was determined. The apparent stability constant, Kc, was calculated from the slope and intercept of the AL solubility diagram as 568 M−1. The solid complexes of NAP with β-CD in 1:1 molar ratio were prepared by the freeze-drying and neutralization method. The formation of an inclusion complex with β-CD in solid state was confirmed by X-ray diffractometry, IR spectroscopy and differential scanning calorimetry (DSC). The dissolution rate of NAP from the inclusion complex was much more rapid than of NAP alone. The amount of NAP released from the tablet surfaces was determined for tablets pressed under 3500 kg/cm2. It was seen that the total released amount of NAP from the NAP/β-CD complex was greater than that of intact NAP.

Inclusion complex formation of piromidic acid (PA) with dimethyl-s-cyclodextrin (DM-s-CD) in aqueous solution and in the solid state was confirmed by the solubility method, differential scanning calorimetry (DSC) and proton nuclear magnetic resonance (1 H-NMR) spectroscopy. The apparent stability constant, K c , of the complex was estimated to be 244 M-1. The stoichiometry of the complex was given as the ratio 1:2 of PA to DM-s-CD. The dissolution rate of the PA/DM-s-CD complex was much greater than that of intact PA.