Preparation, characterization and permeation studies of a nanovesicular system containing diclofenac for transdermal delivery

Budesonide-Loaded Bilosomes as a Targeted Delivery Therapeutic Approach Against Acute Lung Injury in Rats

Budesonide (BUD), a glucocorticoids drug, inhibits all steps in the inflammatory response. It can reduce and treat inflammation and other symptoms associated with acute lung injury such as COVID-19. Loading BUD into bilosomes could boost its therapeutic activity, and lessen its frequent administration and side effects. Different bilosomal formulations were prepared where the independent variables were lipid type (Cholesterol, Phospholipon 80H, L-alpha phosphatidylcholine, and Lipoid S45), bile salt type (Na cholate and Na deoxycholate), and drug concentration (10, 20 mg). The measured responses were: vesicle size, entrapment efficiency, and release efficiency. One optimum formulation (composed of cholesterol, Na cholate, and 10 mg of BUD) was selected and investigated for its anti-inflammatory efficacy in vivo using Wistar albino male rats. Randomly allocated rats were distributed into four groups: The first: normal control group and received intranasal saline, the second one acted as the acute lung injury model received intranasal single dose of 2 mg/kg potassium dichromate (PD). Whereas the third and fourth groups received the market product (Pulmicort® nebulising suspension 0.5 mg/ml) and the optimized formulation (0.5 mg/kg; intranasal) for 7 days after PD instillation, respectively. Results showed that the optimized formulation decreased the pro-inflammatory cytokines TNF-α, and TGF-β contents as well as reduced PKC content in lung. These findings suggest the potentiality of BUD-loaded bilosomes for the treatment of acute lung injury with the ability of inhibiting the pro-inflammatory cytokines induced COVID-19.

Polyacrylamide/poly(2-(dimethylamino) Ethyl Methacrylate) Interpenetrating Polymer Networks as Drug Delivery Systems for Diclofenac Sodium

Nowadays, modern pharmaceutical investigations are directed toward the design and production of drug delivery systems for achieving prolonged and controlled drug delivery. In this respect, the use of interpenetrating polymer networks (IPNs) is an opportunity in the preparation of polymer drug delivery systems with desired characteristics. This paper describes the synthesis and characterization of novel poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) and polyacrylamide (PAAm)-based IPNs with different compositions and their application as diclofenac sodium delivery systems. The prepared IPNs were shown to possess phase-separated structures at the nano level, as revealed by SEM and TM-DSC. The IPNs' composition was shown to determine the swelling behavior of these novel materials, and the inclusion of the charged IPN component (PDMAEMA) has changed the water molecules type diffusion from Fickian to non-Fickian, as revealed by the swelling kinetics study. Loading efficiency of diclofenac sodium and diclofenac sodium content in the polymer network was evaluated, and in vitro drug release experiments were carried out in order to estimate the ability of the obtained IPNs to control the release of the water-soluble drug.

Development and Optimization of Nanolipid-Based Formulation of Diclofenac Sodium: In Vitro Characterization and Preclinical Evaluation

In the present research study, we formulate bilosomes (BMs) of diclofenac (DC) for oral delivery for enhancement of therapeutic efficacy (anti-inflammatory disease). The BMS were prepared by thin film hydration method and optimized by Box−Behnken design (BBD) using cholesterol (A), lipid (B), surfactant (C), and bile salt (D) as formulation factors. Their effects were evaluated on vesicle size (Y1) and entrapment efficacy (Y2). The optimized DC-BMs-opt showed a vesicle size of 270.21 ± 3.76 nm, PDI of 0.265 ± 0.03, and entrapment efficiency of 79.01 ± 2.54%. DSC study result revealed that DC-BMs-opt exhibited complete entrapment of DC in BM matrix. It also depicted significant enhancement (p < 0.05) in release (91.82 ± 4.65%) as compared to pure DC (36.32 ± 4.23%) and DC-liposomes (74.54 ± 4.76%). A higher apparent permeability coefficient (2.08 × 10−3 cm/s) was also achieved compared to pure DC (6.6 × 10−4 cm/s) and DC-liposomes (1.33 × 10−3 cm/s). A 5.21-fold and 1.43-fold enhancement in relative bioavailability was found relative to pure DC and DC liposomes (DC-LP). The anti-inflammatory activity result showed a significant (p < 0.05) reduction of paw edema swelling compared to pure DC and DC-LP. Our findings revealed that encapsulation of DC in BMs matrix is a good alternative for improvement of therapeutic efficacy.

Application of Quality by Design: Development to Manufacturing of Diclofenac Sodium Topical Gel

The objective of the present study was to develop and optimize generic topical gel formulation of diclofenac sodium through quality by design approaches. The quality target product profile was set for the critical quality attributes of the gel. The key material variables like hydrophilic gelling agent carbopol and penetration enhancer kolliphor were optimized using design of experiments. A central composite design was used considering viscosity and cumulative percent diffusion of the drug after 0.5, 1, 2, 4 and 6 h as responses. The p values for all models generated for different responses were statistically significant (<0.5). Design space was established and verified at the laboratory scale. The predicted and observed values were in close agreement. The robustness of the formula was tested at a higher scale (10X and 200X). The capability index was calculated followed by Monte Carlo simulation and the Cpk values for all the responses were more than 1.33.

Performance evaluation of Cryo Laser Phoresis technique as biophysical method to promote diclofenac sodium cutaneous perfusion

ABSTRACT Aiming to alter and/or improve permeation of active compounds in the skin, many strategies have been developed, including biophysical methods. One of the physical absorption techniques, currently known as Cryo Laser Phoresis (CLP), consists of an apparatus that emits radiation on polar or nonpolar molecules of the active substance, resulting in faster penetration when in comparison to the standard topical application. The goal of this work was to evaluate the efficacy of a method that proposes to increase cutaneous permeation of diclofenac sodium by using CLP technique. The influence on permeation was evaluated ex vivo, using Franz cell and human skin obtained from cosmetic surgery. The results were evaluated using statistical methods and data exploratory analysis: clusters, k-means and Principal Component Analysis. The results showed a larger increase in the concentration of diclofenac sodium in the dermis with the use of laser. In all samples (with or without laser application) it was observed that skin surface showed an amount of diclofenac sodium and that there was no active passage to the receptor liquid, suggesting that diclofenac sodium was not absorbed. These results indicate that CLP, when used under the conditions described in this study, is able to increase diclofenac sodium penetration and its retention into deeper layers.

Nanovesicles of nitrendipine with lipid complex for transdermal delivery: pharmacokinetic and pharmacodynamic studies

CONTEXT

Vesicular transdermal delivery can enhance the bioavailability of a drug especially affected by first-pass metabolism, e.g. nitrendipine. However effective transdermal delivery employs permeation enhancer, e.g oleic acid (OA) with ceramide 2, stearic acid, behenic acid, and cholesteryl sulfate lipid complex.

OBJECTIVE

This study investigated the preparation, characterization of physicochemical properties, ex vivo permeation using human skin, pharmacokinetic parameters and antihypertensive potential in rats, of nitrendipine-loaded nanovesicles of ceramide 2, stearic acid, behenic acid and cholesteryl sulfate containing oleic acid gel (NOVG).

MATERIALS AND METHODS

The nanovesicles were made using film hydration method and characterized for physicochemical properties, ex vivo permeation using human skin, pharmacokinetic parameters and antihypertensive potential.

RESULTS

Nitrendipine-loaded nanovesicles of ceramide-2 containing oleic acid (NOV-5) have shown fluxes in the range of 4.88-24.72 μg/cm(2)/h nitrendipine oral suspension (NOS) at equal dose. NOVG-5 has shown almost 33% reduction in blood pressure in the first hour and a further decrease of 25% in the second hour to restore the normal pressure.

DISCUSSION

The permeation increases with increase in OA content. OA gets integrated in vesicle wall and enhances its permeability, whereas ceramide content makes sure that skin does not become damaged even after permeation.

CONCLUSION

NOVG-5 has shown the most favorable physicochemical properties and good permeation through skin providing good management of hypertension during crucial initial hours.

Enhanced delivery of diclofenac diethylamine loaded Eudragit RL 100® transdermal system against inflammation

A transdermal therapeutic system (TTS) of diclofenac diethylamine (DDE) was developed to obtain a prolonged controlled drug delivery by the solvent evaporation technique. The matrix diffusion controlled systems used various combinations of hydrophilic (polyvinylpyrrolidone K30) and lipophilic (Eudragit RL 100® and Eudragit RS 100®) polymers containing dimethyl sulfoxide (DMSO) (0, 5 and 10% w/w) as a penetration enhancer. In vitro drug release was improved with an increased fraction of hydrophilic polymer. Formulation F8 containing Eudragit RL 100® and polyvinylpyrrolidone K30 in the ratio 40:60 presented the highest drug release (92.45%) and permeation rate (0.0988±0.010 mg/cm2/h) with sustained release action for 48 h. In vivo pharmacodynamic study of DDE-loaded Eudragit RL 100® transdermal system (formulation F8) showed significant higher percent inhibition of rat paw edema compared with the marketed formulation of the drug. Our results suggest that a developed formulation is an efficient system for transdermal diclofenac delivery against inflammation. The optimized formulation was found to be stable and did not show physicochemical interaction. The system is envisaged to be stable for a sufficiently long period (2.52 years) at room temperature.

Enhancing Skin Permeation of Biphenylacetic Acid (BPA) Using Salt Formation with Organic and Alkali Metal Bases

In the present study, a series of organic and alkali metal salts of biphenylacetic acid (BPA) have been prepared and evaluated in vitro for percutaneous drug delivery. The physicochemical properties of BPA salts were determined using solubility measurements, DSC, and IR. The DSC thermogram and FTIR spectra confirmed the salt formation with organic and alkali metal bases. Among the series, salts with organic amines (ethanolamine, diethanolamine, triethanolamine, and diethylamine) had lowered melting points while the alkali metal salt (sodium) had a higher melting point than BPA. The in vitro study showed that salt formation improves the physicochemical properties of BPA, leading to improved permeability through the skin. Amongst all the prepared salts, ethanolamine salt (1b) showed 7.2- and 5.4-fold higher skin permeation than the parent drug at pH 7.4 and 5.0, respectively, using rat skin.

Formulation and evaluation of controlled-release of telmisartan microspheres: In vitro/in vivo study

The aim of this work was to design a controlled-release drug-delivery system for the angiotensin-II receptor antagonist drug telmisartan. Telmisartan was encapsulated with different EUDRAGIT polymers by an emulsion solvent evaporation technique and the physicochemical properties of the formulations were characterized. Using a solvent evaporation method, white spherical microspheres with particle sizes of 629.9–792.1 μm were produced. The in vitro drug release was studied in three different pH media (pH 1.2 for 2 hours, pH 6.8 for 4 hours, and pH 7.4 for 18 hours). The formulations were then evaluated for their pharmacokinetic parameters. The entrapment efficiency of these microspheres was between 58.6% and 90.56%. The obtained microspheres showed good flow properties, which were evaluated in terms of angle of repose (15.29–26.32), bulk and tapped densities (0.37–0.53 and 0.43–0.64, respectively), Carr indices and Hausner ratio (12.94–19.14% and 1.14–1.23, respectively). No drug release was observed in the simulated gastric medium up to 2 hours; however, a change in pH from 1.2 to 6.8 increased the drug release. At pH 7.4, formulations with EUDRAGIT RS 100 showed a steady drug release. The microsphere formulation TMRS-3 (i.e., microspheres containing 2-mg telmisartan) gave the highest C_max value (6.8641 μg/mL) at 6 hours, which was three times higher than C_max for telmisartan oral suspension (TOS). Correspondingly, the area under the curve for TMRS-3 was 8.5 times higher than TOS. Particle size and drug release depended on the nature and content of polymer used. The drug release mechanism of the TMRS-3 formulation can be explained using the Higuchi model. The controlled release of drug from TMRS-3 also provides for higher plasma drug content and improved bioavailability.

Formulation of diclofenac for dermal delivery

Diclofenac (DF) was first synthesized in the 1960's and is currently available as ophthalmic, oral, parenteral, rectal and skin preparations. This review focuses on the administration of DF to the skin. As a member of the non-steroidal anti-inflammatory (NSAID) group of drugs the primary indications of DF are for the management of inflammation and pain but it is also used to treat actinic keratosis. The specific aims of this paper are to: (i) provide an overview of the pharmacokinetics and metabolism of DF following oral and topical administration; (ii) examine critically the various formulation approaches which have been investigated to enhance dermal delivery of DF; and (iii) identify new formulation strategies for enhanced DF skin penetration.

Enhanced oral bioavailability of efavirenz by solid lipid nanoparticles: in vitro drug release and pharmacokinetics studies

Solid lipid nanoparticle is an efficient lipid based drug delivery system which can enhance the bioavailability of poorly water soluble drugs. Efavirenz is a highly lipophilic drug from nonnucleoside inhibitor category for treatment of HIV. Present work illustrates development of an SLN formulation for Efavirenz with increased bioavailability. At first, suitable lipid component and surfactant were chosen. SLNs were prepared and analyzed for physical parameters, stability, and pharmacokinetic profile. Efavirenz loaded SLNs were formulated using Glyceryl monostearate as main lipid and Tween 80 as surfactant. ESLN-3 has shown mean particle size of 124.5 ± 3.2 nm with a PDI value of 0.234, negative zeta potential, and 86% drug entrapment. In vitro drug release study has shown 60.6-98.22% drug release in 24 h by various SLN formulations. Optimized SLNs have shown good stability at 40°C ± 2°C and 75 ± 5% relative humidity (RH) for 180 days. ESLN-3 exhibited 5.32-fold increase in peak plasma concentration (C max) and 10.98-fold increase in AUC in comparison to Efavirenz suspension (ES).

Formulation and evaluation of guggul lipid nanovesicles for transdermal delivery of aceclofenac

Context. Most new drugs have low water solubility and liposome is an important formulation to administer such drugs; however, it is quite unstable and has negligible systemic absorption. Objective. Aceclofenac nanovesicles were made using guggul lipid for formulating stable transdermal formulation. Materials and Methods. Guggul lipid was formulated into vesicles along with cholesterol and dicetyl phosphate using film hydration method. The formulations were analyzed for physicochemical properties and stability. Then its skin permeation and anti-inflammatory activity were determined. Results. Both categories of vesicles (PC and GL) showed optimum physicochemical properties; however, accelerated stability study showed considerable differences. GL-1 was appreciably stable for over 6 months at 4°C. Corresponding gels (PCG-1 and GLG-1) showed C_max values at 4.98 and 7.32 μg/mL along with the T_max values at 4 and 8 hours, respectively. GLG-1 inhibited edema production by 90.81% in 6 hours. Discussion. PC liposomes are unstable at higher temperature and upon longer storage. The formulation with higher lipid content (GL-1) showed good drug retention after 24 hours and appreciable stability both at higher temperature and for longer duration. Guggul lipid being a planar molecule might be stacked in vesicle wall with cholesterol. Conclusion. The composition of the nanovesicle played an important role in stability and drug permeation. Guggul lipid is suitable for producing stable vesicles.