Applications of “Smart Polymers” as Biomaterials

Chitosan-Based Nano-Smart Drug Delivery System in Breast Cancer Therapy

Despite recent advances, cancer remains the primary killer on a global scale. Numerous forms of research have been conducted to discover novel and efficient anticancer medications. The complexity of breast cancer is a major challenge which is coupled with patient-to-patient variations and heterogeneity between cells within the tumor. Revolutionary drug delivery is expected to provide a solution to that challenge. Chitosan nanoparticles (CSNPs) have prospects as a revolutionary delivery system capable of enhancing anticancer drug activity and reducing negative impacts on normal cells. The use of smart drug delivery systems (SDDs) as delivering materials to improve the bioactivity of NPs and to understand the intricacies of breast cancer has garnered significant interest. There are many reviews about CSNPs that present various points of view, but they have not yet described a series in cancer therapy from cell uptake to cell death. With this description, we will provide a more complete picture for designing preparations for SDDs. This review describes CSNPs as SDDSs, enhancing cancer therapy targeting and stimulus response using their anticancer mechanism. Multimodal chitosan SDDs as targeting and stimulus response medication delivery will improve therapeutic results.

Microstructured Macromaterials Based on IPN Microgels

This study investigates the formation of microstructured macromaterials from thermo- and pH-sensitive microgels based on interpenetrating networks of poly-N-isopropylacrylamide (PNIPAM) and polyacrylic acid (PAA). Macromaterials are produced as a result of the deposition of microgel particles and subsequent crosslinking of polyacrylic acid subnetworks to each other due to the formation of the anhydride bonds during annealing. Since both PNIPAM and PAA are environment-sensitive polymers, one can expect that their conformational state during material development will affect its resulting properties. Thus, the influence of conditions of preparation for annealing (pH of the solution, the temperature of preliminary drying) on the swelling behavior, pH- and thermosensitivity, and macromaterial inner structure was investigated. In parallel, the study of the effect of the relative conformations of the IPN microgel subnetworks on the formation of macromaterials was carried out by the computer simulations method. It was shown that the properties of the prepared macromaterials strongly depend both on the temperature and pH of the PNIPAM-PAA IPN microgel dispersions. This opens up new opportunities to obtain materials with pre-chosen characteristics and environmental sensitivity.

Nanopolyphenols: a review of their encapsulation and anti-diabetic effects

Polyphenols are believed to possess numerous health benefits and can be grouped as phenolic acids, flavonoids or non-flavonoids. Research involving the synthesis of nanopolyphenols has attracted interest in the areas of functional food, nutraceutical and pharmaceutical development. This is in an effort to overcome current challenges which limit the application of polyphenols such as their rapid elimination, low water-solubility, instability at low pH, and their particle size. In the synthesis of nanopolyphenols, the type of nanocarrier used, the nanoencapsulation technique employed and the type of polymers that constitute the drug delivery system are crucial. For this review, all mentioned factors which can influence the therapeutic efficacy of nanopolyphenols were assessed. Their efficacy as anti-diabetic agents was also evaluated in 33 publications. Among these were phenolic acid (1), flavonoids (13), non-flavonoids (17) and polyphenol-rich extracts (2). The most researched polyphenols were quercetin and curcumin. Nanoparticles were the main nanocarrier and the size of the nanopolyphenols ranged from 15 to 333 nm with encapsulation efficiency and drug loading capacities of 56–97.7% and 4.2–53.2%, respectively. The quantity of nanomaterial administered orally ranged from 1 to 300 mg/kg/day with study durations of 1–70 days. Most studies compared the effect of the nanopolyphenol to its free-form and, in all but three cases, significantly greater effects of the former were reported. Assessment of the polyphenol to understand its properties and the subsequent synthesis of its nanoencapsulated form using suitable nanocarriers, polymers and encapsulation techniques can result in effective therapeutic agents for the treatment of diabetes.