Drug Delivery Letters - Volume 12, Issue 2, 2022

Tablet coating has evolved over the years, and today, there are various types of coating for the delayed release of a drug. Drugs can be enteric-coated to provide delayed release, protect the active pharmaceutical ingredients, minimize undesirable effects, and modify the pharmacokinetic properties of a drug, which will have clinical impacts. Certain types of drugs need to be entericcoated for various reasons, such as gastric irritants or acid-liable drugs. This article will review ethylcellulose and polymethacrylate, their role in an enteric coating, and their process coating parameters. Ethylcellulose can provide a short delayed release; it can be modified by adding pHdependent polymers such as sodium alginate and hydroxypropyl methylcellulose phthalate for a long delayed release. On the other hand, polymethacrylate can also be employed to enteric coat drugs without additional polymers. Polymethacrylate, such as Eudragit®, comes in different grades with varying proportions of polymer ratio, allowing for targeted delayed drug release. These will impact which polymer to be employed. Upon choosing the coating material, modeling can also predict in vitro and in vivo correlation as enteric-coated products can have unpredictable in vivo pharmacokinetic profiles. Today, the trend is moving away from the traditional coating, and towards new polymers, and with digitalization, there is a focus to start using data from laboratory experiments to be integrated with computational modeling, artificial intelligence, and machine learning to accurately predict key process parameters and film properties for high-quality products.

Osteoporosis is a chronic, progressive bone condition that is most prevalent in postmenopausal women and the elderly population. An imbalance in the natural bone remodeling process, which is involved in the formation of bone and resorption, is responsible for osteoporosis, leading to bone fragility. It shows no clinical manifestation until a fracture takes place. Osteoporosis is a global epidemic that reduces the quality of life, increases the chances of disabilities, and adds on a huge financial load. Early diagnosis and treatment can help in preventing the disease. Several drug regimens are used in treating the condition; however, the drugs are accompanied by several adverse effects. Nutraceuticals, like herbs, minerals, vitamins, and dairy products, support skeletal strength and integrity. Therefore, the use of different types of nutraceuticals can improve overall bone strength and provide improved treatment of osteoporosis. The review paper focuses on providing indepth knowledge about the various nutraceuticals that are used in the management of osteoporosis along with the novel nanotechnology-based delivery approaches for enhanced delivery of nutraceuticals as the advent of nanotechnology in pharmaceuticals have opened new avenues in the challenging arena of nutraceuticals for providing benefits like stability, higher efficiency, solubility, enhanced bioavailability, permeability, and production without additives.

Parasitic infections are prime causes of morbidity and mortality worldwide. Significant progress has been made to cure these infections, such as discovering antiparasitic drugs, developing new formulation strategies, site-directed drug delivery, chemotherapy, etc. Synthetic drugs are perilous and have various side effects, leading to the development of drug resistance and loss of health. Herbal medicines are economical and generally free from potential side effects; therefore, they are acclaiming recognition. However, it is difficult to produce antiparasitic vaccines; major efforts have been made and still, there are no licensed vaccines currently available to control human parasitic ailments. This systematic review assesses various techniques for the treatment of parasitic infections. Moreover, the advancements and challenges involved in establishing novel trends in the development of more effective drug delivery systems are also investigated. Over the years, the incidences of several infectious ailments in humans have enhanced and it is estimated to further increase in the future. Over thirty new infective agents have been identified globally in the last 30 years; approximately 60 % of them are from zoonotic sources. Efficient drug delivery plays a key role in treating parasitic infections. The main goal of the modern antiparasitic drug delivery system is to minimize the potential side effects and deliver the drug directly to the target pathogens. Therefore, more sophisticated drug formulations than a simple tablet or solution are necessary for the treatment of many human parasitic diseases.

Background: Microsponge drug delivery systems comprise spherical and porous microspheres for prolonged topical drug delivery. These systems considerably reduce the undesirable side effects, offering improved patient compliance and reduced dosing frequency. Objective: The present study focused on developing topical controlled release preparations of microsponges-loaded gel of clarithromycin to cure bacterial skin infections. Materials and Methods: Four batches of microsponges (F1, F2, F3, and F4) of clarithromycin (CLR) containing fixed amounts of clarithromycin (100 mg), dichloromethane (5 ml), polyvinyl alcohol (5 % w/v) and distilled water (25 ml) with varying polymer concentrations were prepared by the quasi-emulsion solvent diffusion method and evaluated for % Production Yield, % drug content, % encapsulation efficiency, particle size, polydispersity index (PDI) and % drug release characteristics. The selected microsponge formulation (F3) was incorporated in Carpopol 934 gel for topical application. The prepared gel (CLRMS-F3 Gel) was evaluated for physical characteristics, pH, spreadability, viscosity, and in vitro drug release. Furthermore, the gel formulation was compared with pure clarithromycin gel for antibacterial activity against the gram-positive (S. aureus) and gram-negative strain (E. coli.) using the cup and plate method. Results and Discussion: The F3 microsponge formulation exhibited a production yield of 83.75%, drug content (21.5 ± 0.50 %), and encapsulation efficiency of 86.04 ± 2.30%. Their particle size was satisfactory (3.80 ± 0.01 μm), and they were found to be spherical and porous in nature. F3 microsponges released 69.36 ± 1.27% of the drug over a period of 8 hrs and were incorporated into the gel formulations. The gel prepared using F3 microsponges was transparent, homogenous, and exhibited a pH of 6.8 ± 0.02, spreadability of 9.92 ± 0.44 g/cm, and viscosity of 35370.17 ± 493.09 centipoises. The CLRMS-F3 gel released 82.13 ± 0.47% drug in 12 hrs using a zero-order kinetic. The antibacterial activity studies revealed a higher potency against both S. aureus and E. coli of the prepared CLRMS-F3 gel compared to pure CLR gel and azithromycin standard. Conclusion: Based on the above study, it may be concluded that microsponges’ gel formulation can be potentially useful in improving topical drug delivery of antibacterial agents and can give better therapeutic efficacy.

Background: Gallic acid is a natural phenolic compound found in several fruits and medicinal plants. It is reported to have several health-promoting effects, including antioxidant, antiinflammatory, antidiabetic, and antineoplastic properties in gastrointestinal, neuropsychological, metabolic, and cardiovascular disorders. Aims: The aim of the present work was to study the influence of formulation factors on the physicochemical properties of gallic acid-loaded chitosan nanoparticles in order to optimize the formulation. Methods: Active chitosan nanoparticles could be used to support the modification of gallic acid delivery. The nanoparticles were prepared by the emulsification-solvent evaporation method using sonication. A 3-factor, 2-level BBD (Box-Behnken Design) was applied for exploring and optimizing the main effects, quadratic effects, as well as interaction effects of the ingredients of the formulation on the performance of the nanoparticles. The responses like particle size, polydispersity index, zeta potential, and encapsulation efficiency were also determined. Results: The concentration of gallic acid nanoparticles seems to be the most critical element affecting their properties. The concentration of chitosan was increased, which resulted in an increase in particle size. The optimised drug-loaded nanoparticles have a zeta potential of -5.2 mV due to their largely negative surface charge. Although the measured zeta potential was low, the nanoparticle dispersion remained stable, and no significant change in the shape or particle size of the gallic acidloaded chitosan nanoparticles was seen after two weeks at 4°C. The gallic acid-loaded nanoparticles have a particle size of 230 nm. Gallic acid reduced the particle size after it was added. One probable explanation for this is that the loaded medicine increased the cohesive force of the hydrophobic contact, resulting in the size reduction. A formulation was optimised based on the acquired results, and the experimental values were comparable to the expected values. FTIR examination revealed that gallic acid-loaded chitosan nanoparticles displayed both hydrogen bond and ionic interactions, allowing for active agent encapsulation and augmentation. Conclusion: The overall results indicated that by decreasing the chitosan concentration, drug entrapment efficiency increased and gallic acid concentration was the main factor influencing particle size, while entrapment efficiency was predominantly affected by the chitosan concentration.

Background: Obesity, considered a complex condition, is the fastest-growing public health concern worldwide. Its treatment is limited due to the side effects of pharmacological options available, outweighing their benefits. Aim: The present study aims to formulate a novel biodegradable formulation of exenatide for direct brain delivery through the nasal route. Methods: To formulate exenatide loaded poly (lactide-co-glycolide) (PLGA) nanoparticles, a double emulsion (w/o/w) solvent evaporation method was employed. A full factorial (33) design of the experiment was used to optimize the formulation. Results: The entrapment efficiency and particle size of the optimized formulation were found to be 68% and 110 nm, respectively. The in-vitro drug release study indicated the sustained release of 48% drug in 5 days. The safety of drug-loaded PLGA nanoparticles for intranasal delivery was indicated by the sheep nasal toxicity study. The efficacy of the developed nanoparticles was demonstrated by an in-vivo pharmacodynamics study on Albino Wistar rats, showing a 6.2% weight reduction after 30 days of treatment. Conclusion: Thus, exenatide is a novel peptide having significant weight loss benefits and no severe side effects. Long-term studies in at least two or more animal models followed by extensive clinical evaluation can safely result in a product for clinical use.