FORMULATION AND EVALUATION OF BESIFLOXACIN NON-ERODIBLE OCULAR INSERTS

Objective: Ocular inserts offer many advantages over conventional dosage forms, like increased ocular residence, the possibility of releasing a drug at a slow and constant rate, accurate dosing, exclusion of preservatives, and increased shelf life. Besifloxacin is a very important drug for the treatment of infectious conjunctivitis. The present study was aimed to formulate and evaluate Besifloxacin Non-Erodible Ocular Insert using Pullulan and polyvinyl pyrrolidone as a drug reservoir, PEG 400 as a plasticizer, and Eudragit RS-100 as a rate-controlling membrane. Methods: Central composite design was employed to study the effect of independent variables, i.e., effects of Pullulan amount (X1) and PVP (X2) on the dependent variables, i.e., % moisture absorption and In vitro diffusion rate. After evaluation of all thirteen batches of ocular insert reservoir formulation, BSF2 and BSF4 were selected as a satisfactory formulation and was sandwiched between rate-controlling membrane, which was made up of Eudragit RS-100 (3 and 5%). Results: The drug content of all formulations was found to be in the range of 95.33 to 99.89 %. In vitro diffusion of Besifloxacin from reservoir formulations (BSF1 to BSF13) was found to be 62.44 to 70.62 %. In vitro diffusion rate of an ocular insert of Besifloxacin can offer benefits such as increasing residence time, prolonging drug release in the eye for 24 h. Eudragit RS-100, as a sustained drug release polymer, showed promising sustained released action. Conclusion: The study concluded that Besifloxacin non-erodible ocular inserts can be successfully developed using Pullulan and polyvinyl pyrrolidone, which will sustain the release of the drug also reduce the frequency of administration, and thereby may help to improve patient compliance.

Understanding the Importance of Capsules in Dry Powder Inhalers

Pulmonary drug delivery is currently the focus of research and development because of its potential to produce maximum therapeutic benefit to patients by directing the drug straight to the lung disease site. Among all the available delivery options, one popular, proven and convenient inhaler device is the capsule-based dry powder inhaler (cDPI) for the treatment of an increasingly diverse range of diseases. cDPIs use a hard capsule that contains a powder formulation which consists of a mixture of a micronized drug and a carrier usually the lactose, known for its good lung tolerance. The capsule is either inserted into the device during manufacturer or by the patient prior to use. After perforating, opening or cut the capsule in the device, patients take a deep and rapid breath to inhale the powder, using air as the vector of drug displacement. The system is simple, relatively cheap and characterized by a lower carbon footprint than that of pressurized metered dose inhalers. This article reviews cDPI technology, focusing particularly on the importance of capsule characteristics and their function as a drug reservoir in cDPIs.

Electrospun Nanofiber and Cryogel of Polyvinyl Alcohol Transdermal Patch Containing Diclofenac Sodium: Preparation, Characterization and In Vitro Release Studies

Transdermal drug delivery systems (TDDS) have drawn more interest from pharmaceutical scientists because they could provide steady blood levels and prevent the first-pass metabolism over a longer period. Polyvinyl alcohol (PVA) has been widely used in this application due to its biocompatibility, non-toxicity, nanofiber and hydrogel-forming ability. Despite those benefits, their morphology would easily be destroyed by continuous water absorption and contribute to burst drug release due to its hydrophilicity. The aim of this study was to prepare the diclofenac sodium (DS)-medicated dual layer PVA patch using a combination of electrospinning and cryogelation (freeze–thaw) methods to improve the physicochemical properties and drug compatibility and investigate the release of the DS-medicated dual layer PVA patch. Morphological observations using scanning electron microscopy (SEM) verified the polymer−polymer interaction between both layers, whereas Fourier transform infrared (FTIR) spectroscopy has demonstrated the compatibility of DS in PVA matrix up to 2% w/v of PVA volume. The DS loads were found amorphously distributed efficaciously in PVA matrix as no visible spectra of DS–PVA interaction were detected. The DS-medicated dual layer PVA patch with a thicker nanofiber layer (3-milliliter running volume), three freeze–thaw cycles and 2% DS loading labeled as 2%DLB3C show the lowest swelling capacity (18.47%). The in vitro assessment using Franz diffusion cells showed that the 2%DLB3C indicates a better sustained release of DS, with 53.26% of the DS being released after 12 h. The 2%DLB3C owned a flux (Jss) of 0.256 mg/cm2/h and a permeability coefficient (Kp) value of 0.020 cm/h. Thus, the results demonstrate that DS-medicated dual layer PVA patches prepared via a combination of electrospinning and cryogelation are capable of releasing drugs for up to 24 h and can serve as a drug reservoir in the skin, thereby extending the pharmacologic effects of DS.

Antimicrobial Polymer-Based Hydrogels for the Intravaginal Therapies—Engineering Considerations

The review is focused on the hydrogel systems dedicated to the intravaginal delivery of antibacterial, antifungal and anti-Trichomonas vaginalis activity drugs for the treatment of gynaecological infections. The strategies for the enhancement of the hydrophobic drug solubility in the hydrogel matrix based on the formation of bigel systems and the introduction of nano- and microparticles as a drug reservoir are presented. Hydrogel carriers of natural and synthetic pharmacological substances, drug-free systems displaying antimicrobial activity thanks to the hydrogel building elements and systems combining the antimicrobial activity of both drug and polymer building components are distinguished. The design of hydrogels facilitating their administration and proper distribution in the vaginal mucosa and the vagina based on thermoresponsive systems capable of gelling at vaginal conditions and already-cross-linked injectable systems after reaching the yield stress are discussed. In addition, the mechanisms of hydrogel bioadhesion that regulate the retention time in the vagina are indicated. Finally, the prospects for the further development of hydrogel-based drug carriers in gynaecological therapies are highlighted.

Study of elution characteristics of anti-tuberculosis drugs mixed with bone cement

The objective: to assess the elution characteristics of anti-tuberculosis drugs (isoniazid, cycloserine, rifampicin, amikacin, kanamycin, ethambutol) placed into bone cement samples and put in a liquid medium to determine the possibility of using such systems as a drug reservoir.Subjects and methods. For in vitro studies, pure substances of the drugs were used. The spectrophotometry was used to study the elution kinetics of the drugs. Absorption spectra of the drugs in the visible and ultraviolet regions were analyzed to reveal the absorption maxima, and the resistance of the chemical structure of the drugs to heating was assessed. Further, the changes of drug release from hardened bone cement samples under static conditions were studied.Results. It has been found that studied drugs demonstrated satisfactory parameters of thermal stability and elution which makes it possible to use them in a mixture with bone cement.

Nano-Lipidic Carriers as a Tool for Drug Targeting to the Pilosebaceous Units

The pilosebaceous unit is the triad comprising of hair follicle, arrector pilli muscle, and sebaceous gland. Drug delivery to and through the hair follicles has garnered much attention of the researchers and the hair follicles represent an attractive target site via topical applications. They are bordered by capillaries and antigenpresenting cells, connected to the sebaceous glands and the bulge region of the hair follicle anchors the stem cells. The nano lipid carriers have the propensity to penetrate through the skin via transcellular route, intracellular route and follicular route. It has been established that nano lipid carriers have the potential for follicular drug delivery and provide some advantages over conventional pathways, including improved bioavailability, enhanced penetration depth, fast transport into the skin, tissue targeting and form a drug reservoir for prolonged release. This review describes the pilosebaceous unit (PSU) and related diseases and the recent lipid-based nanotechnology approaches for drug delivery to the follicular unit as well as related issues. Different types of nano lipid carriers, including ethosomes, liposomes, nanoparticles, solid lipid nanoparticles (SLNs), and nano lipid carriers (NLCs) have been reported for follicular drug delivery. Targeted drug delivery with nano-lipid carriers has the potential to augment the efficacy of drugs/bioactives to treat diseases of PSU. This review systematically introduces the activities of different formulations and the use of nano lipid carriers in treating PSU related disorders like alopecia, acne, and hirsutism.