Calendula officinalis Linn. (CO) is a popular medicinal plant from the plant kingdom’s Asteraceae family that has been used for millennia. This plant contains flavonoids, triterpenoids, glycosides, saponins, carotenoids, volatile oil, amino acids, steroids, sterols, and quinines. These chemical constituents confer multifaceted biological effects such as anti-inflammatory, anti-cancer, antihelminthic, antidiabetes, wound healing, hepatoprotective, and antioxidant activities. Additionally, it is employed in cases of certain burns and gastrointestinal, gynecological, ocular, and skin conditions. In this review, we have discussed recent research from the last five years on the therapeutic applications of CO and emphasized its myriad capabilities as a traditional medicine. We have also elucidated CO’s molecular mechanisms and recent clinical studies. Overall, this review intends to summarize, fill in the gaps in the existing research, and provide a wealth of possibilities for researchers working to validate traditional claims and advance the safe and effective use of CO in treating various ailments.

Amorphous solid dispersions (ASDs) are among the most popular and widely studied solubility enhancement techniques. Since their inception in the early 1960s, the formulation development of ASDs has undergone tremendous progress. For instance, the method of preparing ASDs evolved from solvent-based approaches to solvent-free methods such as hot melt extrusion and Kinetisol^®. The formulation approaches have advanced from employing a single polymeric carrier to multiple carriers with plasticizers to improve the stability and performance of ASDs. Major excipient manufacturers recognized the potential of ASDs and began introducing specialty excipients ideal for formulating ASDs. In addition to traditional techniques such as differential scanning calorimeter (DSC) and X-ray crystallography, recent innovations such as nano-tomography, transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray microscopy support a better understanding of the microstructure of ASDs. The purpose of this review is to highlight the recent advancements in the field of ASDs with respect to formulation approaches, methods of preparation, and advanced characterization techniques

Purpose: A major challenge in ocular therapeutics is poor bioavailability of drug, 1% or even less of the instilled dose is absorbed and frequent administration of conventional products leads to poor adherence to therapy. Hence the present study is to synthesize N-trimethyl chitosan (TMC), a water-soluble chitosan derivative and to prepare flurbiprofen (FLU):hydroxyl propyl-β-cyclodextrin (HP-β-CD) complex loaded nanoparticles for treatment of bacterial conjunctivitis which aims to increase the residence time in ocular tissue thus enhancing patient compliance and improved efficacy. Methods: TMC was synthesized and characterized by ¹H NMR and FT-IR. TMC and chitosan (CS) nanoparticles containing inclusion complex were prepared by ionic gelation using sodium tripolyphosphate (TPP). The nanoparticles thus obtained were evaluated for particle size, zeta potential, drug entrapment, in-vitro release, in-vitro mucoadhesion and TEM for morphology and irritation potential was evaluated by the HET-CAM technique. Results: N-methyl quaternization of CS was confirmed by ¹H NMR. The particle size and zeta potential of the TMC nanoparticles were found to be 201 ± 1.55 nm and +13.9 ± 1.697 mV and that of CS nanoparticles were 361.2 ± 1.55 nm and +10.9 ± 0.424 mV respectively. The entrapment of FLU- HP-β-CD inclusion complex in polymeric nanoparticles was found to be 10.91 ± 1.541%. The observed in-vitro release profile of TMC nanoparticles indicated characteristic burst release followed by delayed release. HET-CAM studies demonstrated the ocular safety of TMC nanoparticles. Conclusion: The developed TMC nanoparticles offered prolonged release potential for transmucosal ocular delivery of hydrophobic flurbiprofen.

Drug delivery via the pulmonary route is a cornerstone in the pharmaceutical sector as an alternative to oral and parenteral administration. Nebulizer inhalation treatment offers multiple drug admi... Graphical abstract

Background: Adapalene is a promising third generation retinoid used in the topical treatment of acne vulgaris. However, the major drawback associated with conventional topical therapy of Adapalene is the ‘retinoid reaction’ which is dose-dependent and characterized by erythema, scaling and burning sensation at the application sites. Microparticulate drug delivery can play a major role in reducing side effects and providing better patient compliance due to targeted delivery. Methods: Adapalene microparticles were prepared using quasi emulsion solvent diffusion method. The effects of formulation variables including polymer ratios, amounts of emulsifier, drug loading and process variables such as stirring time and speed on the physical characteristics of microparticles were investigated. The developed microparticles were characterized by DSC and SEM. Adapalene microparticles were incorporated into Carbopol 971 NF gel for ease of topical delivery. Results: Adapalene microparticulate topical gel showed sustained drug release over 8 hours in in vitro studies. The amount of drug retained in the rat skin during ex vivo studies was higher in the microparticulate topical gel (227.43 ± 0.83 µg/cm2) as compared to the marketed formulation (81.4 ± 1.11 µg/cm2) after 8 hours indicating localized and sustained drug action that can be useful in treating acne vulgaris. The safety of optimized Adapalene gel determined by skin irritation studies performed on Sprague Dawley rats showed no irritation potential. Conclusion: Microparticles can provide promising carrier systems to deliver Adapalene, improving patient compliance due to enhanced skin deposition, localized and sustained action with reduced associated irritant effects.