Simultaneous determination of tramadol and paracetamol in human plasma using LC-MS/MS and application in bioequivalence study of -fixed-dose combination.

The study aimed to develop a sensitive and high-throughput liquid chromatography coupled with tandem mass spectrometry method to quantify concentrations of tramadol and paracetamol simultaneously in human plasma. Sample preparation involved single-step protein precipitation using methanol and two deuterated internal standards, tramadol D6 and paracetamol D4. Agilent Poroshell 120 EC-C18 (100 × 2.1 mm, 2.1 µm) analytical column was employed to achieve chromatographic separation. Detection was in positive ion multiple reaction monitoring mode. A tailing factor (Tf) of <1.2, separation factor (K prime) of >1.5 from the column dead time and signal-to-noise (S/N) ratio >10, were obtained for analytes and internal standards. The standard curve was linear over the concentration range of 2.5-500.00 ng/mL for tramadol and 0.025-20.00 µg/mL for paracetamol. A small injection volume of 1 µL, low flow rate of 440 µL/min and short analysis time of 3.5 min reduced the solvent consumption, analysis cost and system contamination. The results of method validation parameters fulfilled the acceptance criteria of bioanalytical guidelines. The method was successfully applied to a bioequivalence study of fixed-dose combination products of tramadol and paracetamol in Malaysian healthy subjects.

Simple and high sample throughput LC/ESI-MS/MS method for bioequivalence study of prazosin, a drug with risk of orthostatic hypotension.

OBJECTIVE: The study aimed to develop a rapid, simple and sensitive LC/ESI-MS/MS method to measure prazosin concentration in human plasma and apply bedside sampling in bioequivalence study of two prazosin tablets to resolve the adverse effect of orthostatic hypotension. SIGNIFICANCE: The LC/ESI-MS/MS prazosin method was highly sensitive and selective. Bedside sampling reduced the orthostatic hypotension incidence and subject dropout rate. METHODS: After sample preparation, prazosin and terazosin (IS) were detected on mass spectrometer operating in multiple reaction monitoring mode using positive ionization. Mobile phase flow rate was set at 0.40 mL/min with sample run time of 1.75 min. The bioanalytical method was validated as per EMEA and FDA guidelines. Bedside sampling was performed in bioequivalence study for the first 4 h after dosing. The three primary pharmacokinetic parameters, Cmax, AUC0-t and AUC0-∞ and 90% confidence interval were determined. RESULTS: The small injection volume of 1 µL minimized instrumentation contamination and prolonged the analytical column lifespan. Linearity was obtained between 0.5 and 30.0 ng/mL, with coefficient of determination, r2 ≥ 0.99. The mean extraction recovery of prazosin and IS was >92%, with precision value (CV, %) ≤ 10.3%. Only two orthostatic hypotension adverse events were reported. The two prazosin formulations were found to be bioequivalent. CONCLUSION: The LC/ESI-MS/MS method has shown robustness and reliability exemplified by the incurred sample re-analysis result. Bedside sampling should be proposed for bioequivalence or pharmacokinetic studies of drugs demonstrating adverse event of orthostatic hypotension.

Fast and Sensitive HPLC-ESI-MS/MS Method for Etoricoxib Quantification in Human Plasma and Application to Bioequivalence Study.

Etoricoxib is a non-steroidal anti-inflammatory drug (NSAID) used to treat pain and inflammation. The objective of the current study was to develop a sensitive, fast and high-throughput HPLC-ESI-MS/MS method to measure etoricoxib levels in human plasma using a one-step methanol protein precipitation technique. A tandem mass spectrometer equipped with an electrospray ionization (ESI) source operated in a positive mode and multiple reaction monitoring (MRM) were used for data collection. The quantitative MRM transition ions were m/z 359.15 > 279.10 and m/z 363.10 > 282.10 for etoricoxib and IS. The linear range was from 10.00 to 4000.39 ng/mL and the validation parameters were within the acceptance limits of the European Medicine Agency (EMA) and Food and Drug Analysis (FDA) guidelines. The present method was sensitive (10.00 ng/mL with S/N > 40), simple, selective (K prime > 2), and fast (short run time of 2 min), with negligible matrix effect and consistent recovery, suitable for high throughput analysis. The method was used to quantitate etoricoxib plasma concentrations in a bioequivalence study of two 120 mg etoricoxib formulations. Incurred sample reanalysis results further supported that the method was robust and reproducible.

Sample preparation and quantification of polar drug, allopurinol, in human plasma using LCMSMS.

A fast, selective and reproducible LC-MS/MS method with simple sample preparation was developed and validated for a polar compound, allopurinol in human plasma, using acyclovir as internal standard (IS). Chromatographic separation was achieved using Agilent Poroshell 120 EC-C18 (100 × 2.1 mmID, 2.7 µm) analytical column. The mobile phase was comprised of 0.1%v/v formic acid-methanol (95:05; v/v), at a flow rate of 0.45 mL/min. The effect of different protein precipitation agents used in sample preparation such as methanol, acetonitrile, a mixture of acetonitrile-methanol and a mixture of acetonitrile-acetone were evaluated to optimize the extraction efficiency of allopurinol and IS. The use of acetone-acetonitrile (50:50, v/v) as protein precipitating agent shortened the sample preparation time and improved the recovery of allopurinol to above 93%. The IS-normalised matrix factors at two concentration levels were 1.0, with CV of 5.1% and 4.2%. Allopurinol in plasma was stable at benchtop for 24 h, in autosampler tray for 48 h, in instrumentation room for 48 h, in freezer after 7 freeze-thaw cycles and in freezer for 140 days. Allopurinol stock standard solutions were stable for 140 days at room temperature and in the chiller. The short sample run time of the validated bioanalytical method allowed high throughput analysis of plasma samples in pharmacokinetic study of an allopurinol formulation. The robustness and reproducibility of the bioanalytical method was reaffirmed through incurred sample reanalysis (ISR).

Simple and fast LC-MS/MS method for quantification of terazosin in human plasma and application to bioequivalence study.

A simple, fast and sensitive LC-MS/MS method was developed to quantify terazosin in human plasma. The mobile phase consisted of acetonitrile-0.1% (v/v) formic acid (70:30, v/v). Prazosin was used as internal standard (IS). As deproteinization agent, acetonitrile produced a clean sample. A higher response intensity with more symmetrical peak was obtained using Agilent Poroshell 120 EC-C18 - Fast LC column (100 × 2.1mmID, 2.7 µm) compared with Kinetex XB-C18 (100 × 2.1 mm, 2.6 µm) column. The response of terazosin and IS were approximately two times in citrate phosphate dextrose (CPD) plasma compared with dipotassium ethylenediaminetetraacetic acid (K2EDTA) plasma. Plasma calibration curve was linear from 1.0 to 100.0 ng/mL, with coefficient of determination r2 ≥ 0.99. The within-run and between-run precision values (CV, %) were <5.2% and <7.8%, while accuracy values were 102.8-112.7% and 103.4-112.2%. The extended run accuracy was 98.6-102.8% and precision (CV, %) 4.3-10.4%. The recovery of analyte was >98% and IS >94%. Terazosin in plasma kept at benchtop was stable for 24 h, in autosampler tray for 48 h, in instrumentation room for 48 h, for 7 freeze-thaw cycles and in freezer for 140 days. Terazosin and IS stock standard solutions were stable for 140 days at room temperature and in the chiller. The high throughput method was successfully utilized to measure 935 samples in a bioequivalence study of terazosin.

Simple and rapid LC-MS/MS method for simultaneous determination of flavoxate and 3-methyl-flavone-8-carboxylic acid in human plasma: Application to a bioequivalence study.

A simple, rapid, sensitive, and reproducible LC-MS/MS method was developed for simultaneous quantification of flavoxate and 3-methyl-flavone-8-carboxylic (MFCA) in human plasma, using diphenhydramine HCl as internal standard (IS). The chromatographic separation was achieved using Agilent Poroshell 120 EC-C18 - Fast LC column (100 × 2.1mmID, 2.7 µm) fitted with UHPLC Guard Poroshell 120 EC-C18 (5 × 2.1 mmID, 2.7 µm). The mobile phase consisted of 0.1 % v/v formic acid and acetonitrile (30:70, v/v) run at a flow rate of 0.40 mL/min. The standard calibration curve was linear over the concentration range of 2.00 - 2,000.31 ng/mL and 240.00 - 24,000.04 ng/mL for flavoxate and MFCA. For flavoxate and MFCA, the within-run precision was 0.81-6.67 % and 1.68-4.37 %, while accuracy was 100.21-108.25 % and 103.99-110.28 %. The between-run precision was 2.01-9.14 % and 2.31-11.11 %, and accuracy was 96.09-103.33 % and 102.37-109.52 %. The extended run precision was 7.78-11.04 % and 2.22-3.33 %, while accuracy was 100.72-101.88 % and 102.34-105.60 %. Flavoxate and MFCA in plasma were stable 4 h at bench top (short term), 24 h in autosampler and instrumentation room (post-preparative), after 7 freeze-thaw cycles, and 89 days in the freezer. Both analytes and IS stock solutions were stable for 31 days when kept at room temperature (25 ± 4 °C) and refrigerated (2-8 °C). The validated method was successfully applied to a bioequivalence study of two flavoxate formulations involving 24 healthy volunteers.

Development of LC-MS/MS method and application to bioequivalence study of a light sensitive drug montelukast.

OBJECTIVE: The aim of the study was to develop a simple, highthroughput and sensitive LC-MS/MS method and apply to a bioequivalence study of montelukast, a light sensitive drug. METHOD: The effects of organic modifiers in mobile phase, protein precipitation agent to plasma sample ratio, and light on montelukast stability in unprocessed and processed human plasma, were evaluated. Validation was conducted in accordance with European Medicines Agency Guideline on bioanalytical method validation. RESULTS: No interference peak was observed when acetonitrile was used as an organic modifier. Acetonitrile to plasma ratio of 4:1 produced clean plasma sample. Approximately 3 % of cis isomer was detected in unprocessed plasma samples while 21 % of cis isomer was detected in processed plasma samples after exposing to fluorescent light for 24h. The standard calibration curve was linear over 3.00-1200.00 ng/mL. All method validation parameters were within the acceptance criteria. CONCLUSION: The validated method was successfully applied to a bioequivalence study of two montelukast formulations involving 24 healthy Malaysian volunteers. The light stability of a light sensitive drug in unprocessed and processed human plasma samples should be studied prior to pharmacokinetic/bioequivalence studies. Measures could then be taken to protect the analyte in human plasma from light degradation.

Simple and rapid LC-MS/MS method for determination of sitagliptin in human plasma and application to bioequivalence study.

A simple, rapid, sensitive, and reproducible liquid chromatography-tandem mass spectrometry method was developed to determine sitagliptin in human plasma. Diphenhydramine HCl was used as internal standard (IS). The chromatographic separation was achieved using Agilent Poroshell 120 EC-C18 - Fast LC column (100 × 2.1mmID, 2.7) fitted with UHPLC Guard Poroshell 120 EC-C18 (5 × 2.1mmID, 2.7 µm). The mobile phase consisted of 0.1% v/v formic acid and methanol (45:55, v/v) run at a flow rate of 0.45 mL/min at 30 °C. Methanol produced relatively cleaner plasma sample as deproteinization agent. Polytetrafluoroethylene membrane was preferred over nylon membrane as the former produced clear plasma samples. The standard calibration curve was linear over the concentration range of 5-500.03 ng/mL. The within-run precision was 0.53-7.12% and accuracy 87.09-105.05%. The between-run precision was 4.74-11.68% and accuracy 95.02-97.36%. The extended run precision was 3.60-6.88% and accuracy 93.18-95.82%. The recovery of analyte and IS was consistent. Sitagliptin in plasma was stable at benchtop (short term) for 24 h, in autosampler tray for 48 h, in instrumentation room for 48 h (post-preparative), after 7 freeze-thaw cycles (-20 ± 10 °C), and 62 days in the freezer (-20 ± 10 °C). Both sitagliptin (analyte) and IS stock solutions were stable for 62 days when kept at room temperature (25 ± 4 °C) and in chiller (2-8 °C). The validated method was successfully applied to a bioequivalence study of two sitagliptin formulations involving 26 healthy Malaysian volunteers.

Simultaneous quantification of sildenafil and N-desmethyl sildenafil in human plasma by UFLC coupled with ESI-MS/MS and pharmacokinetic and bioequivalence studies in Malay population.

A simple, rapid, specific and reliable UFLC coupled with ESI-MSMS assay method to simultaneously quantify sildenafil and N-desmethyl sildenafil, with loperamide as internal standard, was developed. Chromatographic separation was performed on a Thermo Scientific Accucore C18 column with an isocratic mobile phase composed of 0.1% v/v formic acid in purified water-methanol (20:80, v/v), at a flow rate of 0.3 mL/min. Sildenafil, N-desmethyl sildenafil and loperamide were detected with proton adducts at m/z 475.4 > 58.2, 461.3 > 85.2 and 477.0 > 266.1 in multiple reaction monitoring positive mode, respectively. Both analytes and internal standard were extracted by diethyl ether. The method was validated over a linear concentration range of 10-800 ng/mL for sildenafil and 10-600 ng/mL for N-desmethyl sildenafil with correlation coefficient (r(2) ) ≥0.9976 for sildenafil and (r(2) ) ≥0.9992 for N-desmethyl sildenafil. The method was precise, accurate and stable. The proposed method was applied to study the bioequivalence between a 100 mg dose of two pharmaceutical products: Viagra (original) and Edyfil (generic) products. AUC0-t , Cmax and Tmax were 2285.79 ng h/mL, 726.10 ng/mL and 0.94 h for Viagra and 2363.25 ng h/mL, 713.91 ng/mL and 0.83 hour for Edyfil. The 90% confidence interval of these parameters of this study fall within the regulatory range of 80-125%, hence they are considered as bioequivalent.

Taste-masked and affordable donepezil hydrochloride orally disintegrating tablet as promising solution for non-compliance in Alzheimer's disease patients.

CONTEXT: Manufacturing process and superdisintegrants used in orally disintegrating tablet (ODT) formulation are often time discussed. However, the effect of suitable filler for ODT formulation is not explored thoroughly. OBJECTIVE: The aim of this study was to develop a novel taste masked and affordable donepezil hydrochloride ODT with fast disintegration time and stable to improve medication compliance of Alzheimer's disease patient. METHODS AND MATERIALS: The ODT was manufactured using simple wet-granulation method. Crospovidone XL-10 was used as superdisintegrant and optimization was done by comparing the effect of three grades of lactose monohydrate compound as filler: Starlac®, Flowlac® and Tablettose®. RESULTS AND DISCUSSION: Formulations containing higher amount of colloidal silicon dioxide showed increase in hardness, weight, disintegration time and wetting time after stability study. Formulation E which containing 50% of Starlac® was found with shortest in vitro disintegration time (21.7 ± 1.67 s), in vivo disintegration time (24.0 ± 1.05 s) and in vitro disintegration time in artificial salvia (22.5 ± 1.67 s). Physical stability studies at 40 °C/75% RH for 6 months, Fourier transform infrared spectroscopy analysis and X-ray diffraction results showed that the formulation was stable. The drug-released profile showed that 80% of donepezil hydrochloride was released within 1 min. A single-dose, fasting, four-period, seven-treatment, double-blinded study involving 16 healthy human volunteers was performed to evaluate the palatability of ODT. Formulation VII containing 10 mg of ammonium glycyrrhizinate was able to mask the bitter taste of the drug. CONCLUSION: The product has the potential to be commercialized and it might serve as solution for non-compliance among the Alzheimer's disease patients.

Improved protein deproteinization method for the determination of meloxicam in human plasma and application in pharmacokinetic study.

A simple, rapid, specific and reliable high-performance liquid chromatographic assay of meloxicam in human plasma has been developed using a C18 reversed-phase analytical column. Reversed-phase chromatography was conducted using a mobile phase of 0.02 potassium dihydrogen phosphate (adjusted to pH 2.7 with phosphoric acid)-acetonitrile-triethylamine (35:65:0.05, v/v) with UV detection at 354 nm. The drug in human plasma was deproteinized using a combination of methanol and chloroform. This method is simple, rapid and consistent with a high recovery of meloxicam in human plasma ranging from 93.29 to 111.09%. Regression analysis for the calibration plot for plasma standards obtained for the drug concentrations between (25-4000) ng/mL indicated excellent linearity (r ≥ 0.9997). The proposed method was applied to study the bioequivalence between Mobic (original) and Melocam (generic) products. The study was conducted on using two tablets (4 × 7.5 mg) of each of the commercial product and the reference standard in a two-way open randomized crossover design involving 20 volunteers. Area under the concentration-time curve, peak concentration (C(max)) and time to reach C(max) were 72,868.61 ng h/mL, 2133.93 ng/mL and 4.06 h for Mobic, and 78,352.52 ng h/mL, 2525.18 ng/mL and 3.61 h for Melocam. Two C(max) were discovered in the pharmacokinetic profiles which confirm enterohepatic recirculation.

Randomized two-way cross-over bioequivalence study of two amoxicillin formulations and inter-ethnicity pharmacokinetic variation in healthy Malay volunteers.

The objectives of this study were to develop a new deproteinization method to extract amoxicillin from human plasma and evaluate the inter-ethnic variation of amoxicillin pharmacokinetics in healthy Malay volunteers. A single-dose, randomized, fasting, two-period, two-treatment, two-sequence crossover, open-label bioequivalence study was conducted in 18 healthy Malay adult male volunteers, with one week washout period. The drug concentration in the sample was analyzed using high-performance liquid chromatography (UV-vis HPLC). The mean (standard deviation) pharmacokinetic parameter results of Moxilen® were: peak concentration (Cmax ), 6.72 (1.56) µg/mL; area under the concentration-time graph (AUC0-8 ), 17.79 (4.29) µg/mL h; AUC0-∞ , 18.84 (4.62) µg/mL h. Those of YSP Amoxicillin® capsule were: Cmax , 6.69 (1.44) µg/mL; AUC0-8 , 18.69 (3.78) µg/mL h; AUC00-∞ , 19.95 (3.81) µg/mL h. The 90% confidence intervals for the logarithmic transformed Cmax , AUC0-8 and AUC0-∞ of Moxilen® vs YSP Amoxicillin® capsule was between 0.80 and 1.25. Both Cmax and AUC met the predetermined criteria for assuming bioequivalence. Both formulations were well tolerated. The results showed significant inter-ethnicity variation in pharmacokinetics of amoxicillin. The Cmax and AUC of amoxicillin in Malay population were slightly lower compared with other populations.

Effect of HPMC concentration on ß-cyclodextrin solubilization of norfloxacin.

The effect of hydroxypropyl methylcellulose (HPMC) concentration on ß-cyclodextrin (ß-CD) solubilization of norfloxacin was examined. The solubility and dissolution of norfloxacin/ß-CD and norfloxacin/ß-CD/HPMC inclusion complexes were studied. The presence of ß-CD increased significantly the solubility and dissolution of norfloxacin. The addition of HPMC until 5% (w/w) improved the solubilization of norfloxacin but further addition above 5% (w/w), decreased norfloxacin solubilization. Fourier transformed Infra-red (FTIR) showed that norfloxacin was successfully included into ß-CD. Differential scanning calorimetry (DSC) showed that the norfloxacin endothermic peak shifted to a lower temperature with reduced intensity indicating the formation of inclusion complex. The addition of HPMC reduced further the intensity of norfloxacin endothermic peak. Most of the sharp and intense peaks of norfloxacin disappeared with the addition of HPMC. In conclusion, the concentration of hydrophilic polymer used to enhance ß-CD solubilization of poorly soluble drugs is very critical.

Effect of polymer, plasticizer and filler on orally disintegrating film.

CONTEXT: Difficulty in swallowing tablets or capsules has been identified as one of the contributing factors to non-compliance of geriatric patients. Although orally disintegrating tablet was designed for fast disintegration in mouth, the fear of taking solid tablets and the risk of choking for certain patient populations still exist. OBJECTIVE: The objective of this study was to develop and characterize orally disintegrating film (ODF), which was prepared using different combinations of polymers, plasticizers and fillers. MATERIALS AND METHODS: Effects of hydroxypropyl methylcellulose (HPMC), polyethylene glycol 400 (PEG 400), glycerin, polyvinyl pyrrolidone (PVP), mannitol and microcrystalline cellulose (MCC) on physical property of ODF formed were studied. The ODF was prepared using the solvent casting method. RESULTS: Increase in HPMC concentration formed ODF with greater tensile strength. Incorporation of plasticizer (PEG 400 and glycerin) reduced tensile strength but increased elasticity of the ODF formed. PVP increased both tensile strength and elasticity of the ODF. Increase in MCC:mannitol ratio reduced the tensile strength and elasticity of the ODF. Disintegration time of film decreased corresponding to decrease in tensile strength of the film. Formulation R with the optimum tensile strength (13.10 N/mm(2)), bending flexibility (40 times) and disintegration time (41.50 s) was chosen as final formulation. A total of 80% of the drug was released within five minutes and the ODF was stable at least for one year actual condition. CONCLUSION: An ODF containing donepezil HCl was developed and characterized. The donepezil HCl ODF has the potential to improve the compliance of Alzheimer disease patients.

Three-ways crossover bioequivalence study of cephalexin in healthy Malay volunteers.

CONTEXT: Although the general pharmacokinetics of cephalexin is quite established up-to-date, however, no population-based study on Cephalexin pharmacokinetics profile in Malay population has been reported yet in the literature. OBJECTIVE: The objective of this study was to investigate the pharmacokinetics and to compare the bioavailability of three cephalexin products, Ospexin® versus MPI Cephalexin® tablet and MPI Cephalexin® capsule, in healthy Malay ethnic male volunteers in Malaysia. MATERIAL AND METHOD: A single dose, randomized, fasting, three-period, three-treatment, three-sequence crossover, open label bioequivalence study was conducted in 24 healthy Malay adult male volunteers, with 1 week washout period. The drug concentration in the sample was analyzed using high performance liquid chromatography. RESULT: The mean (SD) pharmacokinetic parameter results of Ospexin® were Cmax, 17.39 (4.15) µg/mL; AUC0-6, 28.90 (5.70) µg/mL * h; AUC0-∞, 30.07 (5.94) µg/mL * h; while, those of MPI Cephalexin® tablet were Cmax, 18.29 (3.01) µg/mL; AUC0-6, 30.02 (4.80) µg/mL * h; AUC00-∞, 31.33 (5.18) µg/mL * h and MPI Cephalexin® capsule were Cmax, 18.25 (3.92) µg/mL; AUC0-6, 30.04 (5.13) µg/mL * h; AUC0-∞, 31.22 (5.29) µg/mL * h. CONCLUSION: The 90% confidence intervals for the logarithmic transformed Cmax, AUC0-6 and AUC0-∞, of Ospexin® versus MPI Cephalexin® tablet and Ospexin® versus MPI Cephalexin® capsule were between 0.80 and 1.25. Both Cmax and AUC met the predetermined criteria for assuming bioequivalence. The pharmacokinetic profile of cephalexin in Malay population does not vary much from other world population.

Solubilization of beclomethasone dipropionate in sterically stabilized phospholipid nanomicelles (SSMs): physicochemical and in vitro evaluations.

BACKGROUND: The local treatment of lung disorders such as asthma and chronic obstructive pulmonary disease via pulmonary drug delivery offers many advantages over oral or intravenous routes of administration. This is because direct deposition of a drug at the diseased site increases local drug concentrations, which improves the pulmonary receptor occupancy and reduces the overall dose required, therefore reducing the side effects that result from high drug doses. From a clinical point of view, although jet nebulizers have been used for aerosol delivery of water-soluble compounds and micronized suspensions, their use with hydrophobic drugs has been inadequate. AIM: To evaluate the feasibility of sterically stabilized phospholipid nanomicelles (SSMs) loaded with beclomethasone dipropionate (BDP) as a carrier for pulmonary delivery. METHODS: 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy-poly(ethylene glycol 5000) polymeric micelles containing BDP (BDP-SSMs) were prepared by the coprecipitation and reconstitution method, and the physicochemical and in vitro characteristics of BDP-SSMs were investigated. RESULTS: BDP-SSMs were successfully prepared with a content uniformity and reproducibility suitable for pulmonary administration. The maximum solubility of BDP in SSMs was approximately 1300 times its actual solubility. The particle size and zeta potential of BDP-SSMs were 19.89 ± 0.67 nm and -28.03 ± 2.05 mV, respectively. The SSMs system slowed down the release of BDP and all of the aerodynamic values of the aerosolized rehydrated BDP-SSMs were not only acceptable but indicated a significant level of deposition in the lungs. CONCLUSION: The SSM system might be an effective way of improving the therapeutic index of nebulized, poorly soluble corticosteroids.

Characterization of oral disintegrating film containing donepezil for Alzheimer disease.

The aim of this study was to develop a taste-masked oral disintegrating film (ODF) containing donepezil, with fast disintegration time and suitable mechanical strength, for the treatment of Alzheimer's disease. Hydroxypropyl methylcellulose, corn starch, polyethylene glycol, lactose monohydrate and crosspovidone served as the hydrophilic polymeric bases of the ODF. The uniformity, in vitro disintegration time, drug release and the folding endurance of the ODF were examined. The in vitro results showed that 80% of donepezil hydrochloride was released within 5 minutes with mean disintegration time of 44 seconds. The result of the film flexibility test showed that the number of folding time to crack the film was 40 times, an indication of sufficient mechanical property for patient use. A single-dose, fasting, four-period, eight-treatment, double-blind study involving 16 healthy adult volunteers was performed to evaluate the in situ disintegration time and palatability of ODF. Five parameters, namely taste, aftertaste, mouthfeel, ease of handling and acceptance were evaluated. The mean in situ disintegration time of ODF was 49 seconds. ODF containing 7 mg of sucralose were more superior than saccharin and aspartame in terms of taste, aftertaste, mouthfeel and acceptance. Furthermore, the ODF was stable for at least 6 months when stored at 40°C and 75% relative humidity.

Solubility of drugs in aqueous polymeric solution: effect of ovalbumin on microencapsulation process.

Microencapsulation of water-soluble drugs using coacervation-phase separation method is very challenging, as these drugs partitioned into the aqueous polymeric solution, resulting in poor drug entrapment. For evaluating the effect of ovalbumin on the microencapsulation of drugs with different solubility, pseudoephedrine HCl, verapamil HCl, propranolol HCl, paracetamol, and curcuminoid were used. In addition, drug mixtures comprising of paracetamol and pseudoephedrine HCl were also studied. The morphology, encapsulation efficiency, particle size, and in vitro release profile were investigated. The results showed that the solubility of the drug determined the ratio of ovalbumin to be used for successful microencapsulation. The optimum ratios of drug, ovalbumin, and gelatin for water-soluble (pseudoephedrine HCl, verapamil HCl, and propranolol HCl), sparingly water-soluble (paracetamol), and water-insoluble (curcuminoid) drugs were found to be 1:1:2, 2:3:5, and 1:3:4. As for the drug mixture, the optimum ratio of drug, ovalbumin, and gelatin was 2:3:5. Encapsulated particles prepared at the optimum ratios showed high yield, drug loading, entrapment efficiency, and sustained release profiles. The solubility of drug affected the particle size of the encapsulated particle. Highly soluble drugs resulted in smaller particle size. In conclusion, addition of ovalbumin circumvented the partitioning effect, leading to the successful microencapsulation of water-soluble drugs.

Rehydrated sterically stabilized phospholipid nanomicelles of budesonide for nebulization: physicochemical characterization and in vitro, in vivo evaluations.

BACKGROUND: Inhaled corticosteroids provide unique systems for local treatment of asthma or chronic obstructive pulmonary disease. However, the use of poorly soluble drugs for nebulization has been inadequate, and many patients rely on large doses to achieve optimal control of their disease. Theoretically, nanotechnology with a sustained-release formulation may provide a favorable therapeutic index. The aim of this study was to determine the feasibility of using sterically stabilized phospholipid nanomicelles of budesonide for pulmonary delivery via nebulization. METHODS: PEG(5000)-DSPE polymeric micelles containing budesonide (BUD-SSMs) were prepared by the coprecipitation and reconstitution method, and the physicochemical and pharmacodynamic characteristics of BUD-SSMs were investigated. RESULTS: The optimal concentration of solubilized budesonide at 5 mM PEG(5000)-DSPE was 605.71 ± 6.38 µg/mL, with a single-sized peak population determined by photon correlation spectroscopy and a particle size distribution of 21.51 ± 1.5 nm. The zeta potential of BUD-SSMs was -28.43 ± 1.98 mV. The percent entrapment efficiency, percent yield, and percent drug loading of the lyophilized formulations were 100.13% ± 1.09%, 97.98% ± 1.95%, and 2.01% ± 0.02%, respectively. Budesonide was found to be amorphous by differential scanning calorimetry, and had no chemical interaction with PEGylated polymer according to Fourier transform infrared spectroscopy. Transmission electron microscopic images of BUD-SSMs revealed spherical nanoparticles. BUD-SSMs exhibited prolonged dissolution behavior compared with Pulmicort Respules (P < 0.05). Aerodynamic characteristics indicated significantly higher deposition in the lungs compared with Pulmicort Respules. The mass median aerodynamic, geometric standard deviation, percent emitted dose, and the fine particle fraction were 2.83 ± 0.08 µm, 2.33 ± 0.04 µm, 59.13% ± 0.19%, and 52.31% ± 0.25%, respectively. Intratracheal administration of BUD-SSMs 23 hours before challenge (1 mg/kg) in an asthmatic/chronic obstructive pulmonary disease rat model led to a significant reduction in inflammatory cell counts (76.94 ± 5.11) in bronchoalveolar lavage fluid compared with administration of Pulmicort Respules (25.06 ± 6.91). CONCLUSION: The BUD-SSMs system might be advantageous for asthma or chronic obstructive pulmonary disease and other inflammatory airway diseases.

Herbal delivery system for treatment of obesity administration of encapsulated khat-extracts on body weight of rats.

SUMMARY: Obesity is one of the most important problems worldwide. Khat (Catha edulis), an evergreen shrub, is thought to reduce body-weight. Its effect is more prominent when khat leaves are chewed. Thus, anti-obesity effects of khat and its associated side effects may depend on the release rate of its active constituents. The present study aimed to investigate the effect of a selected low dose of dried-khat, extracted, formulated as controlled release delivery systems on the body weight (BW), food intake (FI), cholesterol (CS) and triglyceride (TG) levels in rats. Khat extract (KE) was microencapsulated (KE235) and formulated into a parenteral implant (InjKE235). The effects of KE, KE235 and InjKE235 on BW, FI, CS and TG in rats were investigated. The results showed that microcapsules sustained the khat alkaloid release with T50% 1.58 h for KE235 and 14.41 days for InjKE235. KE and KE235 caused maximum reduction in BW, FI, CS and TG during the first to third weeks but rebound gradually thereafter. On the contrary, InjKE235 exhibited a sustained reduction in BW, FI, CS and TG levels for 2 months. The T50% of KE, KE235 and InjKE235 correlated with the reduction in BW, CS and TG but not with FI. In conclusion, the subcutaneous injection and sustained release rate of khat extract play an important role in enhancing the anti-obesity effect in SD rats.: