Preparation and Characterization of Carvedilol Solid Dispersion by Kneading Method

Solid dispersion using hydrophilic carrier is one of the approaches that has a potential to increase solubility, dissolution rate and consequently the oral bioavailability of poorly-water soluble drugs. In this study, class II drug "Carvedilol" (CVD) was used because of its poor solubility, it serves as a model drug that contributes to irregular dissolution and limited bioavailability. CVD: PVP K30 solid dispersion formulations SD1, SD2 and SD3 were prepared by kneading method at different weight ratios ,1:1; 1:2 and 1:4 respectively and evaluated for drug content, solubility and dissolution rate. Kneading method enhances the stability of drugs and suitable for processing thermolabile substances. The optimum solid dispersion ratio was characterized also for drug-carrier interaction by FTIR spectroscopy, and crystallinity by SEM and PXRD and compared with physical mixture and pure drug powder. The results showed that the solubility of carvedilol increased by increasing the proportion of PVP K30 used in the dispersion of the drug. On the other hand, dissolution study revealed a significant enhancement in the dissolution rate of the drug using solid dispersion compared to pure drug and physical mixture. X-ray diffraction of the solid dispersion suggest that the drug's transformation from crystalline to amorphous form may be responsible for the observed improvement in dissolving rate. The carvedilol solid dispersion improved the solubility and dissolution, which depend on the carrier concentration ratio. The dissolution of drugs increased with an increase in carrier content. The studies of PXRD, SEM, and FTIR revealed the amorphous nature of the drug in solid dispersion. The solid dispersion by kneading approach using PVP K30 as a carrier is a potential method for improving CVD's solubility and dissolution rate

Preparation and Evaluation of Emulgel as Topical Drug Delivery for Nimesulide by Using Conventional Emulsion

Topical drug administration is a mean by which various types of dosage forms such as ointments, creams, gels and emulgels are applied at a specific site of the body such as skin, ophthalmic, vagina and various parts of gastrointestinal tract to   give either local or systemic effect. Nimesulide is non-steroidal anti-inflammatory drug (NSAID) which has good anti-inflammatory, analgesic and antipyretic activity. In this study, eight formulations of nimesulide emulgel containing conventional emulsion were prepared to investigate the effects of different variables on the physical appearance, pH, spreadability, viscosity and in vitro drug release. These variables are the type of oil phase of the emulsion (olive and coconut oil), type and concentration of emulsifying agent (span 80 and tween 80), type of gelling agent (carbopol934 and HPMCK15M), preservative and penetration enhancer. The results revealed that (F4) which consist of 2.5% HPMCK15M, 4% (combination of span80 and tween80), 8% coconut oil and 1% nimesulide was an optimum formulation, since it shows maximum drug release after 7 hrs in addition to excellent physical appearance

FORMULATION AND EVALUATION OF PROCHLORPERAZINE MALEATE SUSTAINED RELEASE FLOATING TABLET

Objective: The objective of this study was to formulate once daily sustained oral release floating tablet of prochlorperazine maleate, this floating tablet has many advantages like reduction in dosing frequency, increase bioavailability, enhance patient compliance, and improve drug solubility.Methods: The prochlorperazine maleate floating tablets were formulated by using hydrophilic swellable polymer and gas generating agent. In this study, 15 formulas were prepared with many variables in order to achieve an optimum dissolution and floating behaviour for the floating tablet. The all prepared formulas were tested for bulk density, tap density, angle of repose, Carr's Index, thickness, weight variation, hardness, friability, drug content, in vitro dissolution test, in vitro buoyancy, and swelling index.Results: Formula (F2) that contain 55% (w/w) hydroxypropyl methylcellulose k4M (HPMCK4M), 5 % (w/w) sodium bicarbonate (NaHCO3) have acceptable flow properties and compressibility index and good physical properties with floating lag time (16±0.57) seconds and total floating time (32±0.29) h with 100% release of prochlorperazine maleate at the end of 24 h. Fourier transform infrared spectroscopy (FTIR) study of optimum formula (F2) showed no chemical interaction between the drug and the excipients that used in the formula.Conclusion: It can be concluded that that the selected formula (F2) can be a promising formula for the preparation of gastro retentive floating drug delivery systems of prochlorperazine maleate

Preparation and in-Vitro Evaluation of Cinnarizine Raft Forming Chewable Tablets

Cinnarizine is an anti-histaminic drug and is mainly used to treat symptoms accompanying motion sickness like vomiting and dizziness. It has low and variable bioavailability due to its low water solubility. Cinnarizine (weakly basic drug) is formulated as raft forming   chewable Tablets to allow its complete dissolution at the stomach to be absorbed at the upper part of small intestine. Raft forming chewable Tablets are formulated by direct compression method using sodium alginate or pectin as raft forming agents. The prepared Tablets were evaluated for their pre and post- compression parameters and they have shown desirable results regarding evaluation of hardness, thickness, % friability, weight variation, content uniformity, raft strength, weight and volume, in addition to in-vitro drug release. Out of all the prepared formulas F1 selected as the optimum formula with 488.1mg raft strength and 92.34% drug release after 24hrs that is promising for the formulation of the raft system. Cinnarizine is an anti-histaminic drug and is mainly used to treat symptoms accompanying motion sickness like vomiting and dizziness. It has low and variable bioavailability due to its low water solubility. Cinnarizine (weakly basic drug) is formulated as raft forming   chewable Tablets to allow its complete dissolution at the stomach to be absorbed at the upper part of small intestine. Raft forming chewable Tablets are formulated by direct compression method using sodium alginate or pectin as raft forming agents. The prepared Tablets were evaluated for their pre and post- compression parameters and they have shown desirable results regarding evaluation of hardness, thickness, % friability, weight variation, content uniformity, raft strength, weight and volume, in addition to in-vitro drug release. Out of all the prepared formulas F1 selected as the optimum formula with 488.1mg raft strength and 92.34% drug release after 24hrs that is promising for the formulation of the raft system

Utilization of Natural Polymer in the Preparation of Oral Jelly of Granisetron

The aim of present study was to formulate and evaluate oral jellies containing granisetron (GSN). This new dosage form was designed for administration of the drug to specific aged patients (i.e. pediatric) in certain condition. GSN is an antiemetic which is usually used for the treatment of nausea and vomiting induced by radiotherapy and chemotherapy. The selection of this dosage form was based on its acceptability by pediatric population, ease of use and no need for water after taking the dose. In this study, two types of natural jellifying agents have been used in different concentrations. The natural jellifying agents which have been used were pectin and sodium alginate. The effect of jellifying agent and their concentrations have been investigated. Oral jell was prepared by heat and congealing method. Then investigations were done by measuring the pH, content uniformity, syneresis, stability, general appearance and production yield. The investigations showed that the formulation F3 with 5% pectin is the best one

Formulation and evaluation of Acyclovir compressed lozenges

Lozenges are formulations of solid dosage form which tend to liquefy in mouth or pharynx. They could be consisting of one or more drugs in a flavored and sweetened base. They are recommended to treat local mouth or pharynx irritation or infection, or they may be used also for systemic combi-   nation of two drugs (Acyclovir and Lidocaine) by pressed coated tablet lozenges. Thus, the lozenges will have both antiviral and local anesthetic effects suitable for the treatment of virus that infects oral cavity.   In this study, nine formulations of acyclovir compressed tablet lozenges were prepared to investigate the effects of type and concentration of binders (gelatin, acacia, and tragacanth) on physical appearance, weight variation, hardness, thickness, friability, dissolving , drug content and in vitro released of drug. Compressed tablet lozenges formula F4 contening (Acacia 10%) as binder was successfully prepared and has been selected as optimum formula  since it released 98% of drug after 45 min, as compared to other formulas.  

Utilization of Natural Polyelectrolytes in the Preparation of Naproxen as Sustained Release Matrix Tablet

Our study demonstrates the preparation of naproxen as a sustained release matrix tablet using polyelectrolyte complexes PECs.The cationic polymer used in this study is chitosan CS while the anionic polymer includes sodium alginate SA, xanthan gum XG or carrageenan CG as anionic polymers. FT-IR spectra of these   complexes were studied to indicate the interactions between polyions. Precompression and compresion parameters were studied including the flowability, tablet hardness, thickness, friability, weight variation, drug content and in vitro release study. The results showed that the release rate of naproxen was decreased in the formulas that contains the physical mixtures comparing to the formulas with single polymer and the formula containing high molecular weight chitosan: xanthan gum CSh: XG physical mixture in 3:1 ratio formed the strongest PEC in which the release rate extended up to 20 hr. In conclusion, this work succeeded in preparation of naproxen as oral sustained release matrix tablet, using a physical mixture of cationic and anionic polymers to form PECs resulting in less frequent dosing and a reduction in gastric irritation

An overview of emulgels for topical application

In recent years, gels have been preferentially used for cosmetics and topical pharmaceutical preparations due to their favorable characteristics, such as being greaseless, readily spreadable and easily removable. However, one obstacle that faced it was the inability to enclose hydrophobic compounds. Therefore, a novel approach was developed to circumvent this limitation by mixing the gel with an emulsion, which led to creation of a new topical drug delivery system known as emulgel. Emulgel preserves all favorable features of gel and provides also dual release for drug, thus can be utilized effectively in controlling release and absorption of medication after topical application. Emulgel preparation requires coherent steps, this includes preparation of emulsion and gel and determining their mixing ratio. Finally, the prepared emulgels should be evaluated to ensure their suitability and efficacy for the topical application

Preparation and in vitro evaluation of synthetic high-density lipoproteins as parenteral drug delivery system for tamoxifen citrate

The aim of this study was to develop a bioinspired drug delivery system for tamoxifen citrate (TC) based on synthetic high density lipoproteins (sHDL). For this purpose, sHDL nanoparticles were prepared from a mimetic peptide (5A peptide) and different lipids using thin film hydration method followed by sonication and thermal cycling. Various formulation parameters including lipid composition, lipid to peptide ratio, and drug to carrier ratio had a remarkable impact on the properties and the release pattern of the nanoparticles. The optimized formula (F14) displayed a spherical morphology, average diameter of (35.7±12.4) nm, and a zeta potential (ζ) equals to (-48.4± 0.5) mV. The encapsulation efficiency and drug loading of F14 were (96.5±0.7%) and (9.65±0.1%), respectively. Besides, F14 showed a good stability in human plasma for 24 hours. The encapsulation of the lipophilic drug within the hydrophobic core of the nanocarrier enabled a slow drug release from nanoparticles which follows a near zero order controlled mechanism. The promising results of this study opens an avenue for using sHDL as a delivery system for administration of TC intravenously. Therefore, the optimized formula is suggested to be subject for future analyses in terms of in vitro cytotoxicity against breast cancer cells and in vivo evaluation in tumor bearing animals

Tamoxifen Citrate- loaded synthetic high-density lipoproteins: Assessment of cellular toxicity in breast cancer cells

Tamoxifen Citrate (TC) is the standard endocrine therapy for estrogen receptor (ER) positive breast cancer. TC is a selective estrogen receptor modulator (SERM) whose estrogenic properties in uterus have been linked to increased side effects like blood clots, endometrial polyps and cancer. Therefore, significant amount of research has been carried out to develop tamoxifen loaded nano-formulations with a preferential accumulation in tumor tissue rather than healthy tissues. Synthetic high-density lipoproteins (sHDL) are novel nanocarriers with inherent active-targeting ability towards tumor cells through the ligand–receptor interaction between apolipoprotein A-I (Apo A-I) and scavenger receptor class B type I (SR-BI) overexpressed in various malignant cells. The current study was carried out to investigate whether encapsulation of TC in sHDL could improve the cytotoxic effect of TC against malignant cells. For this purpose, the cytotoxicity of TC-sHDL was evaluated in MCF-7 cell line in vitro. MTT assay demonstrated the increased cytotoxicity of TC-sHDL against cancer cells as compared with the cytotoxic effect of the free drug