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Despite the promising properties of tea tree oil (TTO) as potential therapeutics for several superficial skin conditions, certain limitations such as physical instability and skin irritation have restricted its widespread use. This study focuses on developing a rationally designed lipid-based nanoformulation (TTO-LNF) in accordance with the US Food and Drug Administration standard using a well-recognized quality-by-design (QbD) approach. Using a mixture experimental design, TTO-LNF has been optimized with 5% TTO, 10% surfactant, 5% co-surfactant, and 80% water, which showed a 14.4 ± 4.4 nm droplet size and 0.03 ± 0.01 polydispersity index (PDI). To ease the topical administration, the TTO-LNF gel formulation was further developed using xanthan gum to achieve the desired viscosity and form a gel. The in vitro antibacterial tests of TTO-LNF showed promising inhibitory effects toward both Gram-negative and Gram-positive bacteria. In fact, a complete growth inhibition of S. epidermidis was observed when exposed to TTO-LNF and TTO-LNF gel for 24 h, showing better activity than antibiotic kanamycin (25 µg/mL). Additionally, the in vitro release study showed a sustained release profile with a 50% release in 24 h, which could be beneficial to reduce the toxicity and thereby improve the therapeutic efficacy for long-acting applications. Furthermore, the formulations were remarkably stable at 40 °C/75% Relative humidity (RH) for at least 4 weeks. Therefore, this study presents a promising strategy to develop a biocompatible and stable formulation that can be used for the topical treatment of skin infections. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is one of the leading causes of death from cancer in women; second only to lung cancer. Tamoxifen (TAM) is a hydrophobic anticancer agent and a selective estrogen modulator (SERM), approved by the FDA for hormone therapy of BC. Despite having striking efficacy in BC therapy, concerns regarding the dose-dependent carcinogenicity of TAM still persist, restricting its therapeutic applications. Nanotechnology has emerged as one of the most important strategies to solve the issue of TAM toxicity, owing to the ability of nano-enabled-formulations to deliver smaller concentrations of TAM to cancer cells, over a longer period of time. Various TAM-containing-nanosystems have been successfully fabricated to selectively deliver TAM to specific molecular targets found on tumour membranes, reducing unwanted toxic effects. This review begins with an outline of breast cancer, the current treatment options and a history of how TAM has been used as a combatant of BC. A detailed discussion of various nanoformulation strategies used to deliver lower doses of TAM selectively to breast tumours will then follow. Finally, a commentary on future perspectives of TAM being employed as a targeting vector, to guide the delivery of other therapeutic and diagnostic agents selectively to breast tumours will be presented. [ABSTRACT FROM AUTHOR]

Insoluble, nanostructured delta inulin particles enhance the immunogenicity of co-administered protein antigens and consequently are used as a vaccine adjuvant (Advax™). To better understand their immunomodulatory properties, the in vitro hydrolysis and in vivo distribution of delta inulin particles were investigated. Delta inulin particle hydrolysis under bio-relevant acidic conditions resulted in no observable change to the bulk morphology using SEM, and HPLC results showed that only 6.1% of the inulin was hydrolysed over 21 days. However, 65% of the terminal glucose groups were released, showing that acid hydrolysis relatively rapidly releases surface bound chemistries. This was used to explain in vivo biodistribution results in which delta inulin particles surface-labelled with fluorescein-5-thiosemicabizide were administered to mice using intramuscular (I.M.) or subcutaneous (S.C.) routes. Comparison analysis of the fluorescence of soluble inulin in the supernatants of homogenised tissues maintained at room temperature or heated to 100 °C to solubilise particulate inulin was used to distinguish between fluorescent probe on soluble inulin and probe bound to inulin within particles. Following both I.M. and S.C. injection delta inulin exhibited a depot behaviour with local injection site residence for several weeks. Over this time, as injection site inulin reduced, there was measurable transport of intact delta inulin particles by macrophages to secondary lymphoid organs and the liver. Ultimately, the injected delta inulin became solubilised resulting in its detection in the plasma and in the urine. Thus injected delta inulin particles are initially taken up by macrophages at the site of injection, trafficked to secondary lymphoid tissue and the liver, and hydrolysed resulting in their becoming soluble and diffusing into the blood stream, from whence they are glomerularly filtered and excreted into the urine. These results provide important insights into the biodistribution of I.M. or S.C. injected delta inulin particles when used as vaccine adjuvants and their method of excretion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel RID-HPLC method development for NAR quantification without derivatization. • Forced degradation was performed to detect degradation peaks and stability of NAR. • The developed method was validated as per FDA guidelines and applied to feed premix. • Greenness profile of the developed method was evaluated using GAPI and AGREE tools. Narasin (NAR) is a commonly used ionophoric antibiotic used in the poultry industry, cattle and pig production both for treating coccidiosis and increasing feed conversion efficiency. To ensure safe administration of NAR into the feed is important to avoid toxicity to farm animals caused by incorporation of large doses or non-homogenous mixing, which requires a simple and sensitive chromatographic method to quantify NAR. However, NAR detection by HPLC is challenging as it lacks a chromophore making it less susceptible to UV and fluorescence detection, and the published analytical methods suffer from disadvantages such as the need for complex derivatization or the use of high volumes of hazardous organic solvents. Herein, a novel, simple, rapid, and cost-effective HPLC method is reported to quantify NAR and a study of forced degradation under acidic, basic, temperature, and oxidative conditions are proposed. The separation was performed using a Phenomenex C18 analytical column (4.6 × 150 mm, 5 μm) and the mobile phase composed of 920 mL methanol, 80 mL water and 10 mL glacial acetic acid. A flow rate of 1 mL/min, and sample injection volume of 50 μL was used to detect NAR using the refractive index detector. The HPLC method was validated according to FDA guidelines and was found to be accurate, precise, sensitive and robust. It was shown to be linear at ranges of 200 to 900 µg/mL with a limit of detection (LOD) and limit of quantitation (LOQ) of 7.1 µg/mL and 21.5 µg/mL respectively. The method was successfully used to quantify the drug in its commercial formulation and a forced degradation study was performed under acidic, basic, temperature, and oxidative conditions. The greenness profile of the method was also investigated and compared to reported methods using the green analytical procedure Index (GAPI), and Analytical GREEnness Metric Approach and Software (AGREE) tools. The results indicated the greenness of the developed method. [ABSTRACT FROM AUTHOR]