Formulation and evaluation of controlled-release matrix systems of ciprofloxacin.

BACKGROUND: Ciprofloxacin is a broad-spectrum fluoroquinolone antibacterial drug to which most Gram-negative and many Gram-positive bacteria are highly susceptible. Fluoroquinolones are administered repeatedly, twice a day for 5 days, during the course of therapy. Hence, they require repeated administration. Ciprofloxacin qualifies as a drug candidate for a controlled-release drug delivery system. OBJECTIVES: The present work was aimed to develop ciprofloxacin hydrochloride-containing matrix tablets by the wet granulation method. MATERIAL AND METHODS: The tablets were prepared using EthocelTM 100 Premium and Eudragit® RS PO (Evonik Laboratory, Mumbai, India) as a rate-controlling polymer. Granular dioctyl phthalate (DCP) was used as a diluent. An isopropyl alcohol and dichloromethane (1:1) mixture was used as a granulating agent. The effect of the formulation variables on tablet performance was examined based on weight variation, hardness, friability, thickness, and drug release profiles. The results suggested that the tablets had good integrity. RESULTS: The tablets were stable for 18 months. Formulation F7 gave a linear release pattern up to 12 h. The release of ciprofloxacin from formulation F7 followed zero-order kinetics. The release mechanism was found to be diffusion-controlled as the Higuchi equation was obeyed. CONCLUSIONS: Ciprofloxacin hydrochloride-containing matrix tablets were prepared successfully. The tablets had good integrity and were found stable for 18 months.

Hydrogel Based Drug Delivery Systems: A Review with Special Emphasis on Challenges Associated with Decontamination of Hydrogels and Biomaterials.

BACKGROUND: Many researches involving the development of new techniques and biomaterials to formulate a suitable drug delivery system and tissue engineering have been conducted. The majority of published literature from these researches emphasizes the production and materials characterization. The safety aspect of hydrogels and biomaterials is a major constraint in their biological applications. OBJECTIVE: The present review article aimed to summarize various literatures that encompass the difficulties encountered with decontamination and sterilization methods in the preparations of biomaterials and especially hydrogels for biological applications. METHOD: We searched for original and review articles from various indexed journals reporting applications of hydrogels and biomaterials in drug delivery systems and the importance of decontamination process for hydrogel containing preparations based on various patents evidences. RESULTS: Despite the vast literature available, limited information regarding the decontamination and sterilization processes related to hydrogels and biomaterials is reported. Sterilization processes to hydrogels are not yet fully explored. Researchers working on hydrogel based systems can consider decontamination of such biomaterial as an important tool to allow for commercialization within the chemical, herbal or pharmaceutical industries. CONCLUSION: Unfortunately, till date, limited papers are available which reported the challenges associated with decontamination methods to prepare hydrogels and biomaterials for biological applications. In conclusion, each case of biomaterial requires individual consideration to decontamination and/or sterilization. This must be submitted to a specific method, but more than one technique can be involved. Physicochemical and biological alterations must be avoided and evaluated by the appropriate assays method. Furthermore, it is also important to consider that each method must be validated depending upon the process variables.

Preparation and characterization of metoprolol tartrate containing matrix type transdermal drug delivery system.

The present study aimed to develop matrix-type transdermal drug delivery system (TDDS) of metoprolol tartrate using polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA). The transdermal films were evaluated for physical parameters, Fourier transform infrared spectroscopy analysis (FTIR), differential scanning calorimetry (DSC), in vitro drug release, in vitro skin permeability, skin irritation test and stability studies. The films were found to be tough, non-sticky, easily moldable and possess good tensile strength. As the concentration of PVA was increased, the tensile strength of the films was also increased. Results of FTIR spectroscopy and DSC revealed the absence of any drug-polymer interactions. In vitro release of metoprolol followed zero-order kinetics and the mechanism of release was found to be diffusion rate controlled. In vitro release studies of metoprolol using Keshary-Chein (vertical diffusion cell) indicated 65.5 % drug was released in 24 h. In vitro skin permeation of metoprolol transdermal films showed 58.13 % of the drug was released after 24 h. In vitro skin permeation of metoprolol followed zero-order kinetics in selected formulations. The mechanism of release was found to be diffusion rate controlled. In a 22-day skin irritation test, tested formulation of transdermal films did not exhibit any allergic reactions, inflammation, or contact dermatitis. The transdermal films showed good stability in the 180-day stability study. It can be concluded that the TDDS of MPT can help in bypassing the first-pass effect and will provide patient improved compliance, without sacrificing the therapeutic advantages of the drugs.

Development and characterization of solid dispersion-microsphere controlled release system for poorly water-soluble drug.

The present study aimed to improve solubility and prolong the release duration of a poorly soluble drug using a combination of two different types of formulations (solid dispersion and microspheres). The solid dispersions were prepared by fusion method using urea and mannitol as hydrophilic carriers. Microspheres were prepared by solvent evaporation method using Eudragit L-100 (EL100) and Eudragit RS PO (ERS) as rate-controlling polymers. Flurbiprofen (FBP)-urea (1:2) solid dispersion and microspheres of FBP-EL-100-ERS (1:0.25:0.75) were used for the development of controlled release formulation by mixing them in different proportions. The FBP-containing formulations were evaluated for percentage yield, drug content, morphology, in vitro release, and in vivo anti-inflammatory activity. The best selected formulation was further evaluated for the controlled and improved effects. SEM photomicrograph confirmed the spherical shape of microspheres and with particle size in the range of 73.5-85.4 µm. In vitro release of FBP from controlled release formulations indicated that the formulation containing solid dispersion:microspheres (1:0.5) yielded prolonged effect up to 10 h. The release kinetics followed zero-order, and the mechanism of drug release was found to be diffusion rate controlled. This formulation had shown better inhibition of edema of rat paw up to 16 h and identified as a suitable product for controlled delivery of FBP. In conclusion, the concept of using a binary mixture of solid dispersion and microspheres can be used for other drugs that exhibit a poor solubility in stomach pH and a faster release in intestinal pH.

Formulation and evaluation of controlled release ethylcellulose and polyethylene glycol microspheres containing metoprolol tartrate.

Metoprolol tartrate is rapidly absorbed from both gastric and intestinal regions, after oral administration. To retard the release rate of the metoprolol tartrate, microspheres were prepared with varying concentrations of a mixture containing ethylcellulose and polyethylene glycol-6000. The prepared microspheres were evaluated for various physicochemical characteristics and in vitro drug release. The percent yield of microspheres was in the range of 75.2-87.3%. The particle size of microspheres was found to be in the range of 73.2-85.5 µm. Fourier transform-infrared spectral analysis and differential scanning calorimetry concluded the absence of any interaction between the drug and the carriers. The release time profile of metoprolol tartrate from microspheres in 0.1 N hydrochloric acid solution was to the extent of 33.4-60.2%. The complete release of metoprolol tartrate occurred from MPT-3 and MPT-4 in phosphate buffer solution (pH 7.4) within 8 and 7 h, respectively, whereas the incomplete release (72.3%) occurred from MPT-1. Nearly, the complete release (98.5%) of metoprolol occurred from MPT-2 in 10 h. Formulation MPT-2 would be a preferred formulation. The release of metoprolol involves diffusion rate limited (R2 = 0.9865) as a mechanism from drug release. The prepared microspheres of metoprolol tartrate eliminate the need for multiple dosing and provide patient compliance.

Norfloxacin and metronidazole topical formulations for effective treatment of bacterial infections and burn wounds.

INTRODUCTION: Our various previous findings have shown the suitability of norfloxacin in the treatment of bacterial infections and burn wounds in alone as well as in combination with Curcuma longa in various topical (ointments, gels, and creams) and transdermal drug delivery systems. AIMS AND METHODS: Keeping these facts in consideration, we have made an another attempt to prepare semisolid formulations containing 1% w/w of norfloxacin and metronidazole with different bases like Carbopol, polyethylene glycol, and hydroxypropylmethyl cellulose for effective treatment of bacterial infections and burn wounds. The prepared formulations were evaluated for physicochemical parameters, in vitro drug release, antimicrobial activity, and burn wound healing properties. RESULTS: The prepared formulations were compared with Silver Sulfadiazine cream 1%, USP. Antimicrobial activity of norfloxacin semisolid formulations was found to be equally effective against both aerobic and anaerobic bacteria in comparison to a marketed formulation of Silver Sulfadiazine 1% cream, USP. Based on the burn wound healing property, the prepared norfloxacin semisolid formulation was found to be in good agreement with marketed Silver Sulfadiazine 1% cream, USP. CONCLUSIONS: These findings suggest formulations containing norfloxacin and metronidazole may also prove as an effective alternative for existing remedies in the treatment of bacterial infections and burn wounds.

Comparative evaluation of transdermal formulations of norfloxacin with silver sulfadiazine cream, USP, for burn wound healing property.

OBJECTIVE: In an attempt to find a better treatment for bacterial infections and burn wounds, various semisolid formulations containing 5% w/w of norfloxacin were prepared and evaluated for physicochemical parameters, in vitro drug release through cellophane membrane, antimicrobial activity, and burn wound healing properties. The prepared formulations were compared with silver sulfadiazine 1% cream, USP. METHODS: Various semisolid formulations were prepared with different bases like Carbopol, polyethylene glycol, and hydroxypropylmethyl cellulose, using standard procedures. The antimicrobial activity of these semisolid norfloxacin formulations, against various strains of aerobic and anaerobic microorganisms, was evaluated by using a standard cup-plate method. The wound healing property was evaluated by measuring the wound contraction and expressed as percentage of contraction of original wound size for each animal group. RESULTS: Antimicrobial activity of norfloxacin semisolid formulations was found to be equally effective against both aerobic and anaerobic bacteria in comparison to a formulation of silver sulfadiazine 1% cream, USP, available on the market. CONCLUSION: The burn wound healing property of the prepared norfloxacin semisolid formulations was found to be in good agreement with silver sulfadiazine 1% cream, USP, available on the market.