Search Results (4)

Protein–polymer bioconjugates offer numerous advantages in biomedical applications by integrating the benefits of functional proteins and tunable synthetic polymers. Developing drug-loaded protein–polymer nanoparticles, with a receptor-targeting protein forming the nanoparticle shell, would be ideal for the targeted delivery of drugs to cancer cells that overexpress specific receptors for more effective cancer therapy. In this study, we report the synthesis of reduction-responsive protein–polymer nanoparticles by a photoinitiated polymerization-induced self-assembly (photo-PISA) approach. Anti-cancer drugs can be efficiently encapsulated at high concentrations within the nanoparticles during the photo-PISA process. These protein–polymer nanoparticles present transferrin (Tf) on their surfaces, capable of targeting the overexpressed Tf receptors found on cancer cells. It was found that the nanoparticles demonstrate enhanced cellular uptake and delivery of the anti-cancer drug, curcumin, to cancer cells via Tf receptor-mediated endocytosis, compared to the control PEGylated nanoparticles that lack targeting capability. Moreover, the nanoparticles can release the encapsulated curcumin in response to a reducing environment, a characteristic of cancer cells compared to health cells. Consequently, the synthesized protein–polymer nanoparticles are more effective in inducing cancer cell death compared to the control nanoparticles, demonstrating their potential as an effective and targeted drug delivery system for cancer therapy. Full article

Alternative environments to real-life have been in recent demand in regard to lighting design and in museums. In this study, the effectiveness of the perception of the museum space in simulations or virtual-based environments is studied. Answers to a questionnaire regarding lighting in four different visual experiences are compared: Real-life, virtual-video-based, virtual-photo-based and virtual-render-based. A total of 117 participants were divided into four visual experience groups. Each group answered the same lighting related questions for four exhibition halls in the Natural History Museum of the University of Pisa (Italy), which is housed in the Monumental Charterhouse of Calci. The answers were analyzed using ANOVA and a T-test. The results show that virtual experiences can be acceptable alternatives to real-life experience as the answers were indifferent in more than half of the criteria, and no criterion was affected significantly by experience, regardless of the hall’s characteristics. However, it was found that the hall’s characteristics also had an impact on the perception of the criteria in different experiences. Controlled artificial lighting or uniformly distributed lighting (full day or artificial light) were found to be more indifferent to the experience. Full article

Polysaccharide coated nanoparticles represent a promising class of environmentally friendly latex to replace those stabilized by small toxic molecular surfactants. We report here an in situ formulation of free-surfactant core/shell nanoparticles latex consisting of dextran-based diblock amphiphilic copolymers. The synthesis of copolymers and the immediate latex formulation were performed directly in water using a photo-initiated reversible addition fragmentation chain transfer-mediated polymerization induced self-assembly strategy. A hydrophilic macromolecular chain transfer-bearing photosensitive thiocarbonylthio group (eDexCTA) was first prepared by a modification of the reducing chain end of dextran in two steps: (i) reductive amination by ethylenediamine in the presence of sodium cyanoborohydride, (ii) then introduction of CTA by amidation reaction. Latex nanoparticles were then formulated in situ by chain-extending eDexCTA using 2-hydroxypropyl methacrylate (HPMA) under 365 nm irradiation, leading to amphiphilic dextran-b-poly(2-hydroxypropyl methacrylate) diblock copolymers (DH_X). Solid concentration (SC) and the average degree of polymerization -$\overline{X_n}$- of PHPMA block (X) were varied to investigate their impact on the size and the morphology of latex nanoparticles termed here SCDH_X. Light scattering and transmission electron microscopy analysis revealed that SCDH_X form exclusively spherical nano-objects. However, the size of nano-objects, ranging from 20 nm to 240 nm, increases according to PHPMA block length. Full article

Polymerization-induced self-assembly (PISA) has become an effective strategy to synthesize high solid content polymeric nanoparticles with various morphologies in situ. In this work, one-step PISA was achieved by in situ photocontrolled bromine-iodine transformation reversible-deactivation radical polymerization (hereinafter referred to as Photo-BIT-RDRP). The water-soluble macroinitiator precursor α-bromophenylacetate polyethylene glycol monomethyl ether ester (mPEG_1k-BPA) was synthesized in advance, and then the polymer nanomicelles (mPEG_1k-b-PBnMA and mPEG_1k-b-PHPMA, where BnMA means benzyl methacrylate and HPMA is hydroxypropyl methacrylate) were successfully formed from a PISA process of hydrophobic monomer of BnMA or HPMA under irradiation with blue LED light at room temperature. In addition, the typical living features of the photocontrolled PISA process were confirmed by the linear increase of molecular weights of the resultant amphiphilic block copolymers with monomer conversions and narrow molecular weight distributions (M_w/M_n < 1.20). Importantly, the photocontrolled PISA process is realized by only one-step method by using in situ photo-BIT-RDRP, which avoids the use of transition metal catalysts in the traditional ATRP system, and simplifies the synthesis steps of nanomicelles. This strategy provides a promising pathway to solve the problem of active chain end (C-I) functionality loss in two-step polymerization of BIT-RDRP. Full article