Background: The usage of natural biomaterials or naturally derived materials intended for interface with biological systems has steadily increased in response to the high demand of amenable materials, which are suitable for purpose, biocompatible and biodegradable. There are many naturally derived polymers which overlap in terms of purpose as biomaterials but are equally diverse in their applications. Methods: This review examines the applications of the following naturally derived polymers; hyaluronic acid, silk fibroin, chitosan, collagen and tamarind polysaccharide (TSP); further focusing on the biomedical applications of each as well as emphasising on individual novel applications. Results: Each of the polymers was found to demonstrate a wide variety of successful biomedical applications fabricated as wound dressings, scaffolds, matrices, films, sponges, implants or hydrogels to suit the therapeutic need. Interestingly, blending and amelioration of polymer structures were the two selection strategies to modify the functionality of the polymers to suit the purpose. Further, these polymers have shown promise to deliver small molecule drugs, proteins and genes as nano-scale delivery systems. Conclusion: The review highlights the range of applications of the aforementioned polymers as biomaterials. Hyaluronic acid, silk fibroin, chitosan, collagen and TSP have been successfully utilised as biomaterials in the subfields of implant enhancement, wound management, drug delivery, tissue engineering and nanotechnology. Whilst there are a number of associated advantages (i.e. biodegradability, biocompatibility, non-toxic, nonantigenic as well as amenability) the selected disadvantages of each individual polymer provide significant scope for their further exploration and overcoming challenges like feasibility of mass production at a relatively low cost.

Background/Objectives: This study aimed to fabricate, optimize, and characterize nanostructured lipid carriers (NLCs) loaded with trans-resveratrol (TRES) as an anti-cancer drug for pulmonary drug delivery using medical nebulizers. Methods: Novel TRES-NLC formulations (F1–F24) were prepared via hot, high-pressure homogenization. One solid lipid (Dynasan 116) was combined with four liquid lipids (Capryol 90, Lauroglycol 90, Miglyol 810, and Tributyrin) in three different ratios (10:90, 50:50, and 90:10 w/w), with a surfactant (Tween 80) in two different concentrations (0.5 and 1.5%), and a co-surfactant, soya phosphatidylcholine (SPC S-75; 50 mg). Results: Amongst the analyzed 24 TR-NLC formulations, F8, F14, and F22 were selected based on their physicochemical stability when freshly prepared and following storage (4 weeks 25 °C), as well as in terms of particle size (<145 nm), polydispersity index (PDI; 96%). Furthermore, F14 showed greater stability at 4 and 25 °C for six months and exhibited enhanced aerosolization performance, demonstrating the greater deposition of TRES in the later stages of the next-generation impactor (NGI) when using an air-jet nebulizer than when using an ultrasonic nebulizer. The F14 formulation exhibited greater stability and release in acetate buffer (pH 5.4), with a cumulative release of 95%. Conclusions: Overall, formulation F14 in combination with an air-jet nebulizer was identified as a superior combination, demonstrating higher emitted dose (ED; 80%), fine particle dose (FPD; 1150 µg), fine particle fraction (FPF; 24%), and respirable fraction (RF; 94%). These findings are promising in the optimization and development of NLC formulations, highlighting their versatility and targeting the pulmonary system via nebulization.

Nanostructured lipid carriers (NLCs) are an emerging drug delivery platform for improved drug stability and the bioavailability of antihypertensive drugs and vasoprotective nutraceutical compounds, such as resveratrol (RV). The objective of this study was to ascertain NLCs’ potential to deliver RV and restore attenuated dilator function, using an ex vivo model of acute hypertension. Trimyristin–triolein NLCs were synthesized and loaded with RV. The uptake of RV-NLCs by human coronary artery endothelial cells (HCAECs) maintained their viability and reduced both mitochondrial and cytosolic superoxide levels. Acute pressure elevation in isolated coronary arteries significantly attenuated endothelial-dependent dilator responses, which were reversed following incubation in RV-NLCs, superoxide dismutase or apocynin (p < 0.0001). RV-NLCs demonstrated a five-fold increase in potency in comparison to RV solution. At elevated pressure, in the presence of RV-NLCs, incubation with Nω-nitro-l-arginine (L-NNA) or indomethacin resulted in a significant reduction in the restored dilator component (p < 0.0001), whereas apamin and TRAM-34 had no overall effect. Incubation with the adenosine monophosphate-activated protein kinase (AMPK) inhibitor dorsomorphin significantly attenuated dilator responses (p < 0.001), whereas the SIRT-1 inhibitor EX-527 had no effect. RV-NLCs improved the impaired endothelial-dependent dilation of small coronary arteries, following acute pressure elevation, via NO and downstream COX elements, mediated by AMPK. We suggest that RV-NLCs are an effective delivery modality for improved potency and sustained drug release into the vasculature. Our findings have important implications for the future design and implementation of antihypertensive treatment strategies.

Resveratrol, a polyphenol stilbenoid obtained primarily from grapes, is usually associated with red wine consumption. Lately, there has been an increased interest in resveratrol as nutraceutical due to its cardioprotective effect and prevention of neuronal degeneration, along with other beneficial pharmacological activities, including chemopreventive action, antiaging, antioxidant, and anti-inflammatory properties. Despite the range of therapeutic effects of resveratrol, its biopharmaceutical properties limit its use because of its poor aqueous solubility, extensive gut metabolism, and rapid excretion resulting in poor bioavailability. To surpass these obstacles, nanotechnology based drug delivery systems are being developed to improve the stability of resveratrol, avert its metabolism, and enhance bioavailability for improved health benefits. This chapter presents the therapeutic potential of resveratrol and highlights the nano- and micro-formulations being investigated for resveratrol encapsulation including liposomes, solid lipid nanoparticles, polymeric nanoparticles, nanosponges, nanosuspensions, and cyclodextrins as carriers.

Traditional medicines, derived from plants, could present alternative treatment strategy for cancer therapy. One such plant is Momordica charantia (MC) which possesses anti-carcinogenic properties. This study investigated the anticancer effect of an ethanol extract of MC fruit, Kuguacin-J (K-J), an isolated compound from the leaves of MC and cisplatin, either alone or combination on healthy MCF-10A mammary cells and compared with breast cancer MCF-7 and MDAMB-231 cell lines. Cell viability was tested using 8 μg/mL and 80 μg/mL doses of MC extract, K-J and cisplatin individually or combined for 24 and 48 hours. Caspase-3- activity was measured in MCF-7 and MDA-MB-231 cells using established methods. The results revealed that MC extract and K-J had no effect on healthy MCF-10A cell viability as compared to cisplatin which induced dose and time-dependent cell death. Similarly, treatment of MCF-7 cells with cisplatin induced cell death at high concentration at both the time points, while MC extract and K-J only induce MCF-7 cell death at high dose after 48 hours only. During combination therapy, both doses of cisplatin enhanced MCF-7 cell death when combined with MC extract or K-J after 24 and 48 hours. In MDAMB-231 cells, the three drugs, either alone or combined, evoked significant cell death at both the doses and time points. All three drugs, at high dose, elicited significant increase in caspase-3- activity in MCF-7 and MDA-MB-231 cells as compared to untreated cells. The results revealed that either MC extract or K-J alone or combined with cisplatin, can elicit significant increase in cell death and caspase–3-activity in MCF-7 and MDA-MB-231cells as compared to untreated cells.