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Despite the availability of a number of efficacious treatments for Parkinson's disease, their limitations and drawbacks, particularly related to low brain bioavailability and associated side effects, emphasize the need for alternative and more effective therapeutic approaches. Nanomedicine, the application of nanotechnology in medicine, has received considerable interest in recent years as a method of effectively delivering potentially therapeutic molecules to the brain. In particular, polymeric nanoparticles, constructed from biodegradable polymer, have shown great promise in enhancing therapeutic efficacy, reducing toxicity, and ensuring targeted delivery. However, their clinical translation remains a considerable challenge. This article reviews recent in vitro and in vivo studies using polymeric nanoparticles as drug and gene delivery systems for Parkinson's disease with their challenges and future directions. We are also particularly interested in the technical properties, mechanism, drugs release patterns, and delivery strategies to overcome the blood–brain barrier. © 2024 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Lipid nanoparticles (LNPs) are the most clinically advanced RNA delivery technology, but their efficiency is limited by low RNA release after endosome disruption. To improve RNA release, an acid‐responsive polymer is synthesized with which to formulate LNPs for RNA encapsulation and release. Specifically, three acid‐responsive poly(lactic acid)‐block‐poly(carboxybetaine) zwitterionic derivatives are designed and synthesized that are cationic and complexed with RNA at pH 7.4, but are neutral following cleavage at endosomal pH, thereby having lower affinity to RNA. The polymers are formulated into each of the clinically approved Onpattro, Moderna, or Pfizer LNP formulations to produce hybrid polymer‐lipid nanoparticles (PLNPs). With the PLNPs, the IC50 values of multiple small interfering RNAs (siRNAs) decreased up to 5.4‐fold compared to parent LNPs in several cell lines. Moreover, messenger RNA (mRNA) transfection increased up to two fold. The acid‐responsive polymers in PLNPs accounted for the enhanced RNA transfection as this phenomenon is lost with acid‐inert polymers. Confocal microscopy confirmed that cytosolic RNA concentration increased using the acid‐responsive polymers; conversely, uptake and endosomal escape are identical to existing LNPs. This confirmed that enhanced RNA transfection is due to increased RNA dissociation from its carrier. The novel polymer represents a versatile strategy to increase RNA transfection from LNPs. [ABSTRACT FROM AUTHOR]

Polymer gels are fascinating soft materials and have become excellent candidates for wearable electronics, biomedicine, sensors, etc. Synthetic gels usually suffer from poor mechanical properties, and integrating good mechanical properties, adhesiveness, stability, and self‐healing performances in one gel is more difficult. Herein, polymerization‐induced self‐assembly (PISA) providing PEG‐gels with an overall improvement in their comprehensive performances is reported. PISA synthesis is carried out in PEG (solvent) to efficiently produce various nanoparticles, which are used as the nanofillers in the subsequent synthesis of PEG‐gels with dynamic micelle‐crosslinked hierarchical structures. Compared to hydrogels, PEG‐gels show excellent long‐term stability due to the nonvolatile feature of PEG solvent. The hierarchical PEG‐gels (with nanofillers) exhibit better mechanical and adhesive properties than the homogeneous‐gels (without nanofillers). The energy dissipation mechanism of the PEG‐gels is analyzed via stress relaxation and cyclic mechanical tests. High‐density hydrogen bonds between the micelles and PAA matrix can be broken and reformed, endowing better self‐healing properties of the dynamic micelle‐crosslinked PEG gels. This work provides a simple strategy for producing hierarchical structural gels with enhanced properties, which offers fundamentals and inspirations for the designing of various advanced functional materials. [ABSTRACT FROM AUTHOR]

Polymeric nanotheranostics have emerged as promising vehicles for diagnosis‐cum‐targeted therapy in solid tumors, offering precise delivery of therapeutic agents at the site of solid tumors and minimizing systemic side effects. This article summarizes the latest developments in using polymeric nanoparticles for specific treatment strategies in solid tumors. It explores the various methods these nanoparticles utilize for targeted medication delivery. This includes passive targeting through the amplified permeability and retention effect, active targeting via interactions between ligands and receptors, and stimuli‐responsive release mechanisms such as pH, temperature, and enzymatic triggers. Furthermore, we highlight recent developments in stimuli‐responsive polymeric nanoparticles, which enable controlled drug release in response to specific cues in the tumor microenvironment, thus enhancing therapeutic efficacy. Also, we focus on the theranostic polymeric nanoparticles, which are used for diagnosing and treating solid tumors. We discuss critical regulatory considerations and the regulatory bodies of different countries that regulate nanomedicines' safety, efficacy, quality, and manufacturing processes. Overall, this review provides insights into the latest innovations in polymeric nanoparticles for targeted therapy in solid tumors, elucidating their mechanisms of action, stimuli‐responsive properties, and regulatory pathways, which collectively contribute to developing effective and safe nanomedicines for cancer treatment. [ABSTRACT FROM AUTHOR]

The remarkable ability of the human immunodeficiency virus (HIV) to evade the host's immune system and conventional antiretroviral therapy, has posed significant challenges in achieving complete eradication of the virus in people living with HIV (PLWHIV). However, nanotechnology has emerged as promising avenue for addressing some of the obstacles associated with the use of antiretroviral drugs by modifying drug molecules in nanoscale dimensions. Hence, the present study explores the utilization of poly(epsilon‐caprolactone) (PCL) as a carrier for encapsulating tenofovir disoproxil fumarate (TDF), offering an alternative treatment approach for HIV infection. TDF‐loaded polymeric nanoparticles were successfully prepared using double emulsion solvent evaporation technique and characterized. The characterization of TDF‐loaded polymeric nanoparticles at varied drug to polymer ratios showed that TDF was loaded in PCL with an encapsulation efficiency and drug loading capacity in the range of 23–46% and 4.8–19.9%, respectively. Of note, the neutralization efficacy of TDF‐loaded polymeric nanoparticles was more improved compared to free TDF. Encapsulation of TDF with PCL did not hinder the antiviral activity of TDF against HIV‐1 infection but rather enhanced its potency. [ABSTRACT FROM AUTHOR]

Polymeric particles less than 100 nm in size (polymer nanoparticles), which are useful in the fields of medicine and so on, are synthesized through emulsion polymerization, wherein surfactants are essential for maintaining their dispersion stability, contaminating particle surfaces and causing high environmental pollution. The soap‐free emulsion polymerization (SFEP) of styrene in a packed reactor using microglass beads enables the synthesis of polymer nanoparticles without surfactants. Ultraviolet irradiation is used for radical polymerization using an initiator during the SFEP of styrene. The reaction space in the packed reactor is controlled by the size of glass beads to be filled in the reactor. A decrease in the size of the glass beads narrows the reaction space, causing the average polystyrene particle size to reach 27.3 nm and suppress convection flow by the wall of the glass beads, thereby limiting particle motion and preventing particle growth through particle collisions. [ABSTRACT FROM AUTHOR]

More sustainable agricultural practices are critical to meeting humanity's food needs while minimizing adverse environmental impacts. Engineered nanomaterials used as nanocarriers promise to reduce the volume of agrochemicals required for crop production but concerns about nanocontamination of agricultural products necessitate the discovery of naturally occurring alternatives. Here, plant‐derived cellulose nanocrystals (CNC) as a "green" alternative to man‐made nanomaterials for the economical delivery of agrochemicals to plants are suggested. Using confocal microscopy and fluorescently labeled CNC, it is demonstrated that CNC can successfully penetrate the plant cell wall and enter cells without causing any negative effects on the overall plant phenotype, genome, and metabolome. The efficiency of CNC to deliver chemicals is demonstrated through in vitro tests involving CNC covalently conjugated with 2,4‐dichlorophenoxyacetic acid (2,4‐D). Plant cell culture experiments confirmed that CNC can be used as a 2,4‐D nanocarrier and reduces the volume of plant growth regulators needed to cultivate plant cells. This work creates a new platform for cyclical agricultural practices where CNC extracted from agricultural waste can be used for the direct delivery of agrochemicals to crops, thereby reducing the environmental burden created by both agricultural waste and excess herbicides. [ABSTRACT FROM AUTHOR]

Engineered nanoparticles have emerged as new types of materials for a wide range of applications from therapeutics to energy. Still, fabricating nanomaterials presenting complex inner morphologies and shapes in a simple manner remains a great challenge. Herein, we report the template‐free one‐pot continuous gradient nanoprecipitation of different types of non‐compatible polymers to spontaneously form nanostructured particles. The continuous addition of antisolvent induces precipitation and (re)organization of polymer chains at the forming particle interface, ultimately and naturally developing complex inner morphologies and shapes while particle grows. This low‐energy‐cost bottom‐up assembly approach applies to various functional polymers, possibly embedded with metal nanoparticles, for continuous growth into well‐organized nanoparticles. UV crosslinking of the particles and core removal allows both confirming the building process and leading to hollow or multivoid nanomaterials. [ABSTRACT FROM AUTHOR]

Polycaprolactone nanoparticles (NPs) were produced in the co‐flow glass capillary device with 250μm tip dimension. NPs size was 990 nm for continuous phase velocity, and uc=0.05m/s and 426 nm for uc=0.2m/s. The droplet formation process in the co‐flow microchannel was also simulated using computational fluid dynamic (CFD). Employing a digital image analysis technique, a cut‐off value of 0.81 for the dispersed phase volume fraction was proposed for the determination of droplet size. A scenario was expressed for NP formation from micro‐droplets. Moreover, after conducting 27 CFD simulations, a dimensionless exponential form correlation was proposed for droplet size estimation. In this generalized map, there were three distinct regions based on the relative capillary numbers of continuous to dispersed phases. It was revealed that at a constant dispersed phase velocity, by increasing the continuous phase velocity, more small NPs are formed. The results show that the ratio of micro‐droplets to NPs size was between 735 and 755. [ABSTRACT FROM AUTHOR]

Antigens incorporated in subunit vaccines are typically poorly immunogenic, so a strong immunostimulant (adjuvant) and/or delivery system is required to boost immunogenicity. In this work, the various functional polymer nanostructures, that is, rods, worms, spheres, and tadpoles are used to develop potent peptide antigen delivery systems. The antigen PADRE-J8 (PJ8), derived from Group A Streptococcus (GAS) M-protein, is either physically mixed or chemically conjugated to polymeric nanoparticles of different shapes. The physical mixture of polymeric nanoparticles and antigen is more effective in inducing antibody production than their chemical conjugates. Moreover, rod-shaped polymeric nanoparticles in physical mixture with PJ8 elicited higher and more opsonic antibody titers than powerful complete Freund's adjuvant (CFA)-adjuvanted antigen. Herein, for the first time it is demonstrated that a) the block copolymer, in nanoparticle form, can act as an immune adjuvant, b) nanoparticle shape plays a crucial role in their immunogenicity, and c) antigen conjugation is not required, nor is antigen encapsulation or absorption. [ABSTRACT FROM AUTHOR]

Cationic nanoparticles (NPs) are preferred for therapeutic applications due to its better uptake by mammalian cells. However, preparing cationic polymeric NPs with stability in wide pH range along with limited toxicity remains a challenge. Dextrin, a carbohydrate‐based natural biological macromolecule holds great potential in biomedical applications. Further, it is an inexpensive and abundant raw material which has high pH stability making it more advantageous over other widely explored macromolecules like chitosan. Herein, we report a simple process for preparing biocompatible cationic dextrin (CD) NPs. A series of CDs were prepared through a single‐step reaction by incorporating quaternary ammonium groups onto the polymeric backbone using varying amount of glycidyltrimethylammonium chloride. Formation of uniform spherical CD NPs having size within 100 nm were achieved by a facile synthesis process of ionic gelation using a biocompatible cross‐linker sodium tripolyphosphate. The prepared CD NPs remained stable across the pH range of 5.5–11 and demonstrated approximately 75% cellular internalization within 6 h. The CD NPs were also found to be both cytocompatible and hemocompatible. Next, the chemotherapeutic drug doxorubicin was encapsulated within CD NPs, which is one of the most common chemotherapeutic agents used for the treatment of various types of cancers including breast, lung, ovarian and bladder. The Dox‐loaded CD NPs showed better drug release at acidic pH conditions and induced more than 80% cell death within 24 h at just 2 μg/ml concentration when tested against HeLa cell lines, thus, proving to be a potential drug delivery vehicle for cancer therapy applications. [ABSTRACT FROM AUTHOR]

Messenger RNA (mRNA)‐based therapies offer enhanced control over the production of therapeutic proteins for many diseases. Their clinical implementation warrants formulations capable of delivering them safely and effectively to target sites. Owing to their chemical versatility, polymeric nanoparticles can be designed by combinatorial synthesis of different ionizable, cationic, and aromatic moieties to modulate cell targeting, using inexpensive formulation steps. Herein, 152 formulations are evaluated by high‐throughput screening using a reporter fibroblast model sensitive to functional delivery of mRNA encoding Cre recombinase. Using in vitro and in vivo models, a polymeric nanoformulation based on the combination of 3 specific monomers is identified to transfect fibroblasts much more effectively than other cell types populating the skin, with superior performance than lipid‐based transfection agents in the delivery of Cas9 mRNA and guide RNA. This tropism can be explained by receptor‐mediated endocytosis, involving CD26 and FAP, which are overexpressed in profibrotic fibroblasts. Structure‐activity analysis reveals that efficient mRNA delivery required the combination of high buffering capacity and low mRNA binding affinity for rapid release upon endosomal escape. These results highlight the use of high‐throughput screening to rapidly identify chemical features towards the design of highly efficient mRNA delivery systems targeting fibrotic diseases. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Block copolymers (BCPs) can automatically assemble into various regulated nanoparticles when they are confined within the emulsion droplet because of the structural frustration of polymer chains and the soft template effect of the oil/water interface. In the past few years, great efforts have been made to regulate the morphologies of the resulting BCP particles. In this review article, various strategies for tuning oil/water interfacial properties to engineer the as‐formed BCP particles were summarized. Then, the comprehensive scenarios of the applications of the resulting BCP particles were discussed. Finally, the future tendency and challenge of the self‐assembly of BCPs confined in emulsion droplet were suggested. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Block copolymers (BCPs) can automatically assemble into various regulated nanoparticles when they are confined within the emulsion droplet because of the structural frustration of polymer chains and the soft template effect of the oil/water interface. In the past few years, great efforts have been made to regulate the morphologies of the resulting BCP particles. In this review article, various strategies for tuning oil/water interfacial properties to engineer the as‐formed BCP particles were summarized. Then, the comprehensive scenarios of the applications of the resulting BCP particles were discussed. Finally, the future tendency and challenge of the self‐assembly of BCPs confined in emulsion droplet were suggested. [ABSTRACT FROM AUTHOR]

Herein, the synthesis of three different macromolecular DO3A@Gn conjugates based on poly(2‐oxazoline)s is presented. Therefore, poly(2‐methyl‐2‐oxazoline) is synthesized by a ring‐opening, cationic polymerization and the polymerization is terminated with DO3A(tBu)3. The best results are obtained after 48 h at 120 °C with degree of termination of 86%. After deprotection of the DO3A ligand and complexation with Gn3+, relaxivity as measured with a magnetic field strength of 9.4 T (400 MHz) reveals values for r1 of up to 2.32 mm−1 s−1. The concept is extended to a block copolymer based on 2‐heptyl‐2‐oxazoline and 2‐methyl‐2‐oxazoline that is again terminated with DO3A(tBu)3 to form micelles with a size of 12.6 ± 0.7 nm after DO3A(tBu)3 termination and deprotection of the 1,4,7,10‐tetraazacyclododecane‐N,N,N,N‐tetraacetic acid ligand. After complexation with Gn3+, relaxivity r1 is 10.1 mm−1 s−1 as determined from the slope of the plot of 1/T1 against the gadolinium(III) concentration at 9.4 T. Finally, crosslinked nanoparticles are prepared from amphiphilic macro‐monomers that form micelles in water and are crosslinked throughout the core in the presence of azoisobutyronitrile (AIBN). The nanoparticle is 32.9 ± 7.8 nm in size after Gn3+ complexation and reveals a relaxivity r1 of 6.77 mm−1 s−1. [ABSTRACT FROM AUTHOR]

Transmission electron microscopy (TEM) observations of negatively stained cell membrane (CM)‐coated polymeric nanoparticles (NPs) reveal a characteristic core‐shell structure. However, negative staining agents can create artifacts that complicate the determination of the actual NP structure. Herein, it is demonstrated with various bare polymeric core NPs, such as poly(lactic‐co‐glycolic acid) (PLGA), poly(ethylene glycol) methyl ether‐block‐PLGA, and poly(caprolactone), that certain observed core‐shell structures are actually artifacts caused by the staining process. To address this issue, fluorescence quenching was applied to quantify the proportion of fully coated NPs and statistical TEM analysis was used to identify and differentiate whether the observed core‐shell structures of CM‐coated PLGA (CM−PLGA) NPs are due to artifacts or to the CM coating. Integrated shells in TEM images of negatively stained CM−PLGA NPs are identified as artifacts. The present results challenge current understanding of the structure of CM‐coated polymeric NPs and encourage researchers to use the proposed characterization approach to avoid misinterpretations. [ABSTRACT FROM AUTHOR]

Garlic oil (GO) and cinnamon oil (CO) was successfully loaded in chitosan (CS) based polymeric nanoparticles (NPs). Fumigant, contact toxicities and persistent efficacy of these new Chitosan nano particles (CSNPs) were examined against Tribolium castaneum (T. castaneum) as a common stored product pest. Different ratios of polymer to sodium tripolyphosphate cross‐linker were applied for NPs preparation. Stability of CSNPs loaded with oils was examined for 4 months. Bioassay tests were used to determine LC50 values for fumigant toxicity evaluation and contact effects on red flour beetle, T. castaneum. The optimized CSNPs containing GO and CO had the particle size of 231.1 ± 7.5 nm and 303.4 ± 10 nm with encapsulation efficiency of 76.78% and 86.81%, respectively. Characterization results based on transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD) indicated the successful formation of CSNPs with spherical morphology, amorphous property, and high stability during the storage time. LC50 index of pure oils and their nanoformulations suggested that CSNPs loaded oils have higher fumigant and contact effects on T. castaneum in a lower concentration than pure oils. Lethal effectiveness of CSNPs loaded GO and CO against T. castaneum were 18 and 20 days, respectively. However, GO and CO pure oils lost their efficacy in 10 and 14 days after exposure, respectively. [ABSTRACT FROM AUTHOR]

Background: Collagen forms a dermal matrix in the skin. Biosynthesis and decomposition of collagen are the major processes in skin aging. Propolis is rich in flavonoids and phenolic compounds, which are known to be effective in preventing skin aging, including the enhancement of fibroblast proliferation, activation, and growth capacity. Objectives: The aim of this study was to develop a poorly soluble propolis extract as an active ingredient in cosmetic products for anti‐aging efficacy. Methods & Results: Polymeric nanoparticles containing propolis extract, polyethylene glycol 400, and poloxamer 407 were prepared via a temperature‐induced phase transition method. The particle size of the polymeric nanoparticles was approximately 20.75 nm. The results of an in vitro procollagen type I carboxy‐terminal peptide assay and a matrix metalloproteinase‐1 inhibition assay showed that the polymeric nanoparticles increased collagen production by 19.81%–24.59% compared to blank (p < 0.05), and significantly reduced intracellular collagenase activity by 7.46%–31.52% compared to blank (p < 0.05). In a clinical trial, polymeric nanoparticles in a cosmetic formulation were applied around the eyes of 24 female subjects for 8 weeks. Five skin parameters were significantly improved after the application of the test ampoule. Visual evaluation using the Global Photo Damage Score showed a significant reduction in wrinkles after the application of the test ampoules (p < 0.001). Conclusions: This study outlines the development of stable polymeric nanoparticles containing poorly soluble propolis in a cosmetic formulation, and its efficacy in wrinkle improvement. The developed polymeric nanoparticles were effective for alleviating wrinkles and can be used for pharmaceutical applications that utilize propolis as antiseptic, anti‐inflammatory, antimycotic, antifungal, antibacterial, antiulcer, anticancer, and immunomodulatory agents. [ABSTRACT FROM AUTHOR]

The development of gene delivery systems is essential to improve their transfection efficiency and cytotoxicity. Combination of lipid and polymeric nanoparticles with the characteristics of both systems have been considered as a next‐generation gene delivery platform. In the current study, we designed a novel and efficient targeted gene delivery system based on liposome and PAMAM dendrimer in cancer cells. Two polymeric formulations containing polyamidoamine‐TAT (PAMAM‐TAT) and PAMAM‐TAT‐Hyaluronic acid (HA) and two lipopolymeric carriers including PAMAM‐TAT‐Liposome and PAMAM‐TAT‐HA‐Liposome were complexed with the enhanced green fluorescent protein (EGFP) plasmid and then evaluated in terms of physicochemical characteristics. The cytotoxicity and transfection efficiency of these synthetized carriers were accomplished against murine colon carcinoma cell line (C26). The biodistribution of polyplexes and lipoployplexes was also evaluated in the C26 tumor bearing mice. The results showed no significant toxicity for all designed nanoparticles (NPs) in C/P4. The highest gene expression was observed using lipopolyplex PAMAM‐TAT‐HA‐Liposome in C/P4 (ratio polymer/DNA; wt/wt). Biodistribution study demonstrated more aggregation of targeted lipopolyplex in tumor cells than other nanoparticles (NPs). It could be concluded that the developed targeted lipopolymeric complex could serve as promising nanotherapeutic system for gene therapy. [ABSTRACT FROM AUTHOR]

Epilepsy is the second most prevalent neurological disease worldwide. It is mainly characterized by an electrical abnormal activity in different brain regions. The massive entrance of Ca2+ into neurons is the main neurotoxic process that lead to cell death and finally to neurodegeneration. Although there are a huge number of antiseizure medications, there are many patients who do not respond to the treatments and present refractory epilepsy. In this context, nanomedicine constitutes a promising alternative to enhance the central nervous system bioavailability of antiseizure medications. The encapsulation of different chemical compounds at once in a variety of controlled drug delivery systems gives rise to an enhanced drug effectiveness mainly due to their targeting and penetration into the deepest brain region and the protection of the drug chemical structure. Thus, in this review we will explore the recent advances in the development of drugs associated with polymeric and lipid‐based nanocarriers as novel tools for the management of epilepsy disorders. [ABSTRACT FROM AUTHOR]

Zeta potential is an essential surface parameter in the characterization of nanoparticles, determined at the interface of loosely bound ions (diffuse layer) at the nanoparticle surface and free ions in solution. The ionic concentration and pH of the solution are known to, by definition, influence the composition of the diffuse layer and zeta potential accordingly. Thus, to fix the solution's pH for valid zeta potential measurements, buffers are frequently used. However, an issue that remains largely neglected is that buffers could also additionally alter the electrokinetic properties of nanoparticles through specific molecular interactions. Therefore, a thorough molecular understanding of buffer–nanoparticle interactions is needed to correctly implement zeta potential results. Thus, in order to study nanoparticle–buffer interactions, we first adopted a simple experimental approach of measuring zeta potential of common polymeric nanoparticle systems at different buffer concentrations, pH, and nanoparticle–buffer fraction ratios. We observed that zwitterionic/cationic buffer molecules impart significant interference to the electrokinetic properties of structurally diverse polymer nanoparticles, by causing zeta potential suppression or even inversion during the experiments. In parallel, advancement in computation resources nowadays allow studying intermolecular interactions of nanoparticles and other complex molecules by molecular dynamics (MD) simulations. Thus, by performing MD simulations for six different polymeric nanomaterials with commonly used buffer molecules, we found that noncovalent interactions play a significant role in altering the observed zeta potential values, which may contribute to erroneous results and false particle characterizations if not taken properly into account in zeta potential measurements. [ABSTRACT FROM AUTHOR]

Poly(thioether‐ester) (PTEe) nanoparticles obtained by thiol‐ene polymerization have received attention of many researchers due to several advantages, including, biocompatibility and biodegradability. The search for new nanomaterials requires toxicity studies to assess potential toxic effects of their administration. Therefore, the aim of this study was to evaluate the in vivo acute toxicity of PTEe and poly(thioether‐ester)‐coated magnetic nanoparticles prepared by thiol‐ene polymerization in miniemulsion. These nanoparticles presented a mean size of approximately 120 nm, spherical morphology, and negative surface charge. Doses of 40 mg/kg were administered intraperitoneally to Swiss mice and nociceptive, behavioral and biochemical parameters were investigated in five different organs. None of the nanoparticles led to any alterations in the nociceptive and behavioral responses. Biochemical alterations were observed in liver, decreasing the sulfhydryl and glutathione (GSH) levels, suggesting the dependence of the GSH metabolism in the elimination of the nanoparticles. In general, both nanoparticle types did not cause disturbances in biochemical parameters analyzed in others organs. These results suggest that both nanoparticle types did not induce acute toxicity to the different organs evaluated, reinforcing the biocompatibility of PTEe nanoparticles synthetized by thiol‐ene polymerization. [ABSTRACT FROM AUTHOR]

Polymeric nanoparticles, micelles, niosomes, hydrogels and liposomes represent effective drug carriers having huge potential for medical and pharmaceutical applications. These systems remain the most important area in medicinal chemistry research. The aforementioned biomaterials can effectively encapsulate and release diverse hydrophobic/hydrophilic therapeutic molecules including drugs and prodrugs. Applications of these carrier systems extend to nucleic acids, antibodies and proteins which could be released sustainably. Since these systems fall in the nano dimension, they are capable of enhancing the therapeutic efficacy of bioactive molecules besides enabling them to accumulate preferentially at the target site. Furthermore, these systems can protect the encapsulated drug from degradation, thereby increasing the therapeutic value of the drug candidate and reducing systemic toxicity. In this review, we illustrate the preparative methods and actions of these five drug delivery systems. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a devastating neurodegenerative disease affecting a large proportion of older adults. Exposure to pesticides like rotenone is a leading cause for PD. To reduce disease progression and prolong life expectancy, it is important to target disease mechanisms that contribute to dopaminergic neuronal atrophy, including mitochondrial dysfunction. Achieving targeted mitochondrial delivery is difficult for many therapeutics by themselves, necessitating higher therapeutic doses that could lead to toxicity. To minimize this adverse effect, targeted nano‐carriers such as polyanhydride nanoparticles (NPs) can protect therapeutics from degradation and provide sustained release, enabling fewer administrations and lower therapeutic dose. This work expands upon the use of the polyanhydride NP platform for targeted drug delivery by functionalizing the polymer with a derivative of triphenylphosphonium called (3‐carboxypropyl) triphenylphosphonium (CPTP) using a novel method that enables longer CPTP persistence on the NPs. The extent to which neurons internalized both nonfunctionalized and functionalized NPs was tested. Next, the efficacy of these nanoformulations in treating rotenone‐induced mitochondrial dysfunction in the same cell line was evaluated using a novel neuroprotective drug, mito‐metformin. CPTP functionalization significantly improved NP internalization by neuronal cells. This was correlated with significant protection by CPTP‐functionalized, mito‐metformin encapsulated NPs against rotenone‐induced mitochondrial dysfunction. However, nonfunctionalized, mito‐metformin encapsulated NPs and soluble mito‐metformin administered at the same dose did not significantly protect cells from rotenone‐induced toxicity. These results indicate that the targeted NP platform can provide enhanced dose‐sparing and potentially reduce the occurrence of systemic side‐effects for PD therapeutics. [ABSTRACT FROM AUTHOR]

How nanoparticle (NP) mechanical properties impact multivalent ligand–receptor‐mediated binding to cell surfaces, the avidity, propensity for internalization, and effects due to crowding remains unknown or unquantified. Through computational analyses, the effects of NP composition from soft, deformable NPs to rigid spheres, effect of tethers, the crowding of NPs at the membrane surface, and the cell membrane properties such as cytoskeletal interactions are addressed. Analyses of binding mechanisms of three distinct NPs that differ in type and rigidity (core‐corona flexible NP, rigid NP, and rigid‐tethered NP) but are otherwise similar in size and ligand surface density are reported; moreover, for the case of flexible NP, NP stiffness is tuned by varying the internal crosslinking density. Biophysical modeling of NP binding to membranes together with thermodynamic analysis powered by free energy calculations is employed, and it is shown that efficient cellular targeting and uptake of NP functionalized with targeting ligand molecules can be shaped by factors including NP flexibility and crowding, receptor–ligand binding avidity, state of the membrane cytoskeleton, and curvature inducing proteins. Rational design principles that confer tension, membrane excess area, and cytoskeletal sensing properties to the NP which can be exploited for cell‐specific targeting of NP are uncovered. [ABSTRACT FROM AUTHOR]

Herein, a class of novel photoswitchable tristate fluorescent polymeric nanoparticles (TS‐PFPNs) consisting of a well‐designed perylenediimide‐spiropyran conjugate (PDI‐SP), two energy‐matched photochromics as spiropyran‐linked methacrylate and diarylethene (DTE) derivative (DTEo‐1) is described. By optimizing the feed ratio of three dyes and controllable switching fluorescence resonance energy transfer from excited PDI to SP or DTE moiety with different lights stimuli, the emission of these TS‐PFPNs can be reversibly switched among distinguishable green, red, and quenching states. In addition, these TS‐PFPNs exhibit high brightness, high contrast, excellent water‐dispersibility, and photoreversibility as well as outstanding long‐term storage stability and processability. It is also demonstrated that these TS‐PFPNs can be directly used for advanced anticounterfeiting, high‐density data storage, and multilevel information encryption. [ABSTRACT FROM AUTHOR]

In recent years, polymeric nanoparticles (NPs) have become increasingly popular for in vitro and in vivo bioimaging because of their excellent versatility and exceptional optical properties. Following a brief introduction on fluorescence and photoacoustic imaging, as well as the merits of using polymeric NPs over other types of fluorescent probes, this Minireview gives a concise summary of key advances made in recent years (2017–2020) in the use of polymeric NPs for fluorescence and photoacoustic imaging. A particular focus is placed on various strategies used for enhanced bioimaging applications, including polymeric NPs that encapsulate near‐infrared dyes, aggregation‐induced‐emission fluorogens, cationic dyes doped with bulky hydrophobic counterions, and semiconducting polymers. Next, the current limitations in some of these polymeric NP systems are summarized and potential solutions offered to overcome them. Finally, some critical considerations in regard to the design of polymeric NPs are given for future bioimaging and sensing applications. [ABSTRACT FROM AUTHOR]

Neurological disorders such as Alzheimer's disease, stroke, and brain cancers are difficult to treat with current drugs as their delivery efficacy to the brain is severely hampered by the presence of the blood–brain barrier (BBB). Drug delivery systems have been extensively explored in recent decades aiming to circumvent this barrier. In particular, polymeric nanoparticles have shown enormous potentials owing to their unique properties, such as high tunability, ease of synthesis, and control over drug release profile. However, careful analysis of their performance in effective drug transport across the BBB should be performed using clinically relevant testing models. In this review, polymeric nanoparticle systems for drug delivery to the central nervous system are discussed with an emphasis on the effects of particle size, shape, and surface modifications on BBB penetration. Moreover, the authors critically analyze the current in vitro and in vivo models used to evaluate BBB penetration efficacy, including the latest developments in the BBB‐on‐a‐chip models. Finally, the challenges and future perspectives for the development of polymeric nanoparticles to combat neurological disorders are discussed. [ABSTRACT FROM AUTHOR]

The current pandemic of coronavirus disease 2019 (COVID‐19) is recognized as a public health emergency of worldwide concern. Nanomaterials can be effectively used to detect, capture/inactivate or inhibit coronavirus cell entry/replication in the human host cell, preventing infection. Their potential for nanovaccines, immunoengineering, diagnosis, repurposing medication, and disinfectant surfaces targeting the novel coronavirus (SARS‐CoV‐2) is highlighted. In this systematic review the aim is to present an unbiased view of which and how nanomaterials can reduce the spread of COVID‐19. Herein, the focus is on SARS‐CoV‐2, analyzing 46 articles retrieved before December 31, 2020. The interface between nanomaterials is described, and the main mechanisms to inhibit SARS‐CoV‐2 pathogenesis and viral inactivation are also discussed. Nanocarbons, biopolymeric, copper, and silver nanoparticles are potential antiviral and virucidal agents toward self‐cleaning and reusable filter media and surfaces (e.g., facial masks), drug administration, vaccines, and immunodiagnostic assays. Trends in toxicology research and safety tests can help fill the main gaps in the literature and overcome health surveillance's challenges. Phytochemicals delivery by nanocarriers also stand out as candidates to target and bio‐friendly therapy. Nanocellulose might fill in the gaps. Future research using nanomaterials targeting novel therapies/prophylaxis measures to COVID‐19 and future outbreaks is discussed. [ABSTRACT FROM AUTHOR]

Poly(vinyl pivalate) (PVPi) nanoparticles obtained via miniemulsion have particular properties useful for several applications. Thus, the present study aims to synthesize and characterize PVPi nanoparticles through the miniemulsion polymerization process, studying the effects of water‐soluble and oil‐soluble initiators, polymerization temperature, and the co‐stabilizer concentration on the final properties of the polymer, nanoparticle size, and conversion. The polymeric nanoparticles are characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H and 13C NMR), thermogravimetric analysis, differential scanning calorimetry, gel permeation chromatography, dynamic light scattering, and transmission electron microscopy. The miniemulsion polymerization process ensures the formation of a polymeric fluid with high colloidal and thermal stability, with maximum conversions of ≈85% and average particle diameter of 97.2 ± 21.8 nm. The polymeric properties, such as molar mass and glass transition temperature (Tg), are influenced by process variables such as synthesis temperature and the type of initiator. The use of potassium persulfate and 2,2‐azobisisobutyronitrile (AIBN) initiators favors the homogeneous nucleation mechanism, resulting in a decrease in the average particle diameter and in the growth of the chains, result in greater average molar masses and, consequently, greater Tg. [ABSTRACT FROM AUTHOR]

In the present work, curcumin in combination with (±) α‐Lipoic acid were used as the active agents for the preparation of phosphorylated chitosan nanoparticle. Ionic gelation method was used for the successful fabrication of the nanoparticles. Effective incorporation of the drugs in the polymeric system was revealed by Fourier‐transform infrared spectroscopy (FT‐IR) and X‐ray diffractometry (XRD). Scanning electron microscope, transmission electron microscope and dynamic light scattering method were used to analyze the morphology and dimensional characteristics of the nanoparticles. The swelling degree and drug release mechanism were studied at pH 5.0 and 7.4 for different time periods by UV‐visible spectrophotometer. Cytotoxicity study was performed by MTT assay analysis on normal human lymphocyte and MDA MB 231 breast cancer cell line. Trypan blue dye exclusion assay was performed to confirm the anticancer effect of the nanoparticles. The properties of the prepared nanoparticles recommended their possible application as anticancer agents. [ABSTRACT FROM AUTHOR]

The combination of chemotherapy and photodynamic therapy (PDT) has promising potential in the synergistic treatment of cancer. However, chemotherapy and photodynamic synergistic therapy are impeded by uncontrolled chemotherapeutics release behavior, targeting deficiencies, and hypoxia‐associated poor PDT efficacy in solid tumors. Here, a platinum nanozyme (PtNP) loaded reactive oxygen species (ROS)‐responsive prodrug nanoparticle (CPT‐TK‐HPPH/Pt NP) is created to overcome these limitations. The ROS‐responsive prodrug consists of a thioketal bond linked with camptothecin (CPT) and photosensitizer‐2‐(1‐hexyloxyethyl)‐2‐devinyl pyropheophorbide‐a (HPPH). The PtNP in CPT‐TK‐HPPH/Pt NP can efficiently catalyze the decomposition of hydrogen peroxide (H2O2) into oxygen to relieve hypoxia. The production of oxygen can satisfy the consumption of HPPH under 660 nm laser irradiation to attain the on‐demand release of CPT and ensure enhanced photodynamic therapy. As a tumor diagnosis agent, the results of photoacoustic imaging and fluorescence imaging for CPT‐TK‐HPPH/Pt NP exhibit desirable long circulation and enhanced in vivo targeting. CPT‐TK‐HPPH/Pt NPs effectively inhibit tumor proliferation and growth in vitro and in vivo. CPT‐TK‐HPPH/Pt NP, with its excellent ROS‐responsive drug release behavior and enhanced PDT efficiency can serve as a new cancer theranostic agent, and will further promote the research of chemophotodynamic synergistic cancer therapy. [ABSTRACT FROM AUTHOR]

Cerebral ischemia is a major cause of death in both neonates and adults, and currently has no cure. Nanotechnology represents one promising area of therapeutic development for cerebral ischemia due to the ability of nanoparticles to overcome biological barriers in the brain. ex vivo injury models have emerged as a high‐throughput alternative that can recapitulate disease processes and enable nanoscale probing of the brain microenvironment. In this study, we used oxygen–glucose deprivation (OGD) to model ischemic injury and studied nanoparticle interaction with microglia, resident immune cells in the brain that are of increasing interest for therapeutic delivery. By measuring cell death and glutathione production, we evaluated the effect of OGD exposure time and treatment with azithromycin (AZ) on slice health. We found a robust injury response with 0.5 hr of OGD exposure and effective treatment after immediate application of AZ. We observed an OGD‐induced shift in microglial morphology toward increased heterogeneity and circularity, and a decrease in microglial number, which was reversed after treatment. OGD enhanced diffusion of polystyrene‐poly(ethylene glycol) (PS‐PEG) nanoparticles, improving transport and ability to reach target cells. While microglial uptake of dendrimers or quantum dots (QDs) was not enhanced after injury, internalization of PS‐PEG was significantly increased. For PS‐PEG, AZ treatment restored microglial uptake to normal control levels. Our results suggest that different nanoparticle platforms should be carefully screened before application and upon doing so; disease‐mediated changes in the brain microenvironment can be leveraged by nanoscale drug delivery devices for enhanced cell interaction. [ABSTRACT FROM AUTHOR]

Cancer possesses normoxic and hypoxia microenvironments with different levels of oxygen, needing different efficacies of photothermal and photodynamic therapies. It is important to precisely tune the photothermal and photodynamic effects of phototherapy nano‐agents for efficient cancer treatment. Now, a series of copolymeric nanoparticles (PPy‐Te NPs) were synthesized in situ by controlled oxidative copolymerization with different ratios of pyrrole to tellurophene by FeCl3. The photothermal and photodynamic effects of semiconducting nano‐agents under the first near‐infrared (NIR) irradiation were precisely and systematically tuned upon simply varying the molar ratio of the pyrrole to tellurophene. The PPy‐Te NPs were used for cancer treatment in mice, exhibiting excellent biocompatibility and therapeutic effect. This work presents a simple method to tune photothermal and photodynamic therapies effect in semiconducting nano‐agents for cancer treatment. [ABSTRACT FROM AUTHOR]

Drug encapsulation in nanocarriers such as polymeric nanoparticles (Nps) may help to overcome the limitations associated with cannabinoids. In this study, the authors' work aimed to highlight the use of electrospraying techniques for the development of carrier Nps of anandamide (AEA), an endocannabinoid with attractive pharmacological effects but underestimated due to its unfavourable physicochemical and pharmacokinetic properties added to its undesirable effects at the level of the central nervous system. The authors characterised physicochemically and evaluated in vitro biological activity of anandamide/ɛ‐polycaprolactone nanoparticles (Nps‐AEA/PCL) obtained by electrospraying in epithelial cells of the human proximal tubule (HK2), to prove the utility of this method and to validate the biological effect of Nps‐AEA/PCL. They obtained particles from 100 to 900 nm of diameter with a predominance of 200–400 nm. Their zeta potential was −20 ± 1.86 mV. They demonstrated the stable encapsulation of AEA in Nps‐AEA/PCL, as well as its dose‐dependent capacity to induce the expression of iNOS and NO levels and to decrease the Na+ /K+ ATPase activity in HK2 cells. Obtaining Nps‐AEA/PCL by electrospraying would represent a promising methodology for a novel AEA pharmaceutical formulation development with optimal physicochemical properties, physical stability and biological activity on HK2 cells. [ABSTRACT FROM AUTHOR]

L‐theanine is present in tea as a unique, free, non‐protein amino acid. Due to various beneficial effects on brain activity, it is widely used as a nutraceutical. After consumption, it is rapidly absorbed and metabolised followed by excretion through urine. Therefore, the authors developed an L‐theanine delivery system by encapsulating into polymeric nanoparticles to release it slowly and make it available for a longer period of time. Poly(D, L‐lactic acid) nanoparticle (PLANP) was fabricated by the double emulsion method and L‐theanine was encapsulated into it (PLANP‐T). Spherical nanoparticles with a hydrodynamic diameter of 247 and 278 nm and surface charge of −14.5 and −25.7 mV for PLANP and PLANP‐T, respectively, were fabricated. The Fourier transform infrared spectroscopic data indicated encapsulation of L‐theanine into PLANP. The PLANP showed high L‐theanine encapsulation capacity (71.65%) with a sustained release character. The maximum release (66.3%) of L‐theanine was recorded in pH 7.3 at 48 h. The release kinetics followed the Higuchi model and the release mechanism was determined as super case‐II transport (erosion). This slow release will make it available to the target tissue for a longer period of time (sustain release effect) and will also avoid immediate metabolism and clearance from the circulation. [ABSTRACT FROM AUTHOR]

Imaging‐guided disease theranostic nanoplatforms based on polymeric micelles have drawn a broad attention because of their clear visualization, reduced systemic toxicity, enhanced utilization of drugs, and suppressed chemoresistance of tumors, which makes them possess potential application for cancer therapy. Herein, we synthesized a polymeric nanoparticles (Poly(MAD‐alt‐OCE)‐PTZ‐PEG) with novel aggregation‐induced emission (AIE) characteristic based on cheap commercial polymer by the simple and environmental method. These Poly(MAD‐alt‐OCE)‐PTZ‐PEG nanoparticles (NPs) show excellent biocompatibility and fluorescence property, which makes them huge application potential for cellular imaging. Furthermore, the antitumor drug cisplatin Pt(IV) can be loaded efficiently onto the surface of Poly(MAD‐alt‐OCE)‐PTZ‐PEG NPs due to the existence of abundant carboxyl groups on the NPs surface. The well‐controlled Pt(IV)‐loaded yield and great acid‐responsive drug release of these polymeriec micelles enhance cytotoxicity against cancer cells in vitro. Given the cheap raw materials, eco‐friendly method, excellent AIE property, efficient antitumor drug delivery and pH‐controlled drug release, these polymeric NPs would be a potential candidate for cancer diagnosis and therapy in the future. Imaging‐guided disease theranostic nanoplatforms based on polymeric micelles have drawn a broad attention because of their clear visualization, enhanced utilization of drugs, and suppressed chemoresistance of tumors. We developed a facile method to prepare AIE‐active fluorescent polymeric micelles (Poly(MAD‐alt‐OCE)‐PTZ‐PEG) with excellent biocompatibility, great bioimaging ability and high‐efficiency drug‐loaded ability based on cheap commercial polymer. The better antineoplastic ability of these polymeric NPs makes them become a potential candidate for cancer diagnosis and therapy in the future. [ABSTRACT FROM AUTHOR]

This contribution describes a simple method for preparing polymeric nanoparticles using photodimerization of anthracene moieties on the side chain of terpolymers in dilute regime and transformation of obtained polymeric nanoparticles into pyrene functional nanoparticles via Menschutkin quaternization procedure. Subsequently, pyrene possessing polymeric nanoparticles are attached onto multiwalled carbon nanotube (MWCNT) surfaces by π–π stacking strategy. Gel permeation chromatography, thermal gravimetric analysis, ultraviolet–visible, and fluorescence spectroscopies are used to analyze modified nanoparticles and their precursors. Electron microscopy and dispersion studies show that pyrene‐modified polymeric nanoparticles are able to interconnect various CNTs. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2709–2714 The polymeric nanoparticles are synthesized by radical copolymerization and photodimerization protocols. Achieved nanoparticles are modified by a pyrene derivative. Carbon nanotube particles are easily interconnected by pyrene functionalized nanoparticles via noncovalent interactions. [ABSTRACT FROM AUTHOR]

Abstract: Herein, a versatile threshold temperature sensor based on the glass transition temperature‐triggered fluorescence activation of a dye/developer duo, encapsulated in polymeric nanoparticles is reported. The emission enhancement, detectable even by unaided eye is completed within a narrow temperature range and activates at adjustable threshold temperatures up to 200 °C. Fluorescence is chosen as sensing probe due to its high detection sensitivity together with an advanced spatial and temporal resolution. The strategy is based on nanoparticles prepared from standard thermoplastic polymers, a fluorescence developer, and the commercially available Rhodamine B base dye, a well‐known and widely used fluorescent molecule. By making nanoparticles of different thermoplastic polymers, fast, abrupt, and irreversible disaggregation induced fluorescence enhancement, with tunable threshold temperature depending on the nanoparticles polymer glass transition is achieved. As a proof‐of‐concept for the versatility of this novel family of NPs, their use for sensing the thermal history of environments and surfaces exposed to the threshold temperature is showed. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) is the white blood cell cancer in children. L‐asparaginase (L‐ASNase) is one of the first drugs used in ALL treatment. Anti‐tumor activity of L‐ASNase is not specific and indicates limited stability in different biological environments, in addition to its quick clearance from blood. The purpose of the present study was to achieve a new L‐ASNase polymer bioconjugate to improve pharmacokinetic, increase half‐life and stability of the enzyme. The conjugations were achieved by the cross‐linking agent of 1‐ethyl‐3‐(3‐ dimethylaminopropyl) carbodiimide (EDC) which activates the carboxylic acid groups of polymeric nanoparticles to create amide bond. EDC conjugated the L‐ASNase to two biodegradable polymers including; Ecoflex® and poly (styrene‐co‐maleic acid) (PSMA) nanoparticles. To achieve optimal L‐ASNase nanoparticles the amounts of each polymer and the crosslinker were optimized and the nanoparticles were characterized according to their particle size, zeta potential and percent of conjugation of the enzyme. The results showed that conjugated enzyme had more stability against pH changes and proteolysis. It had lower Km value (indicating more affinity to the substrate) and greater half‐life in plasma and phosphate buffered saline, in comparison to native enzyme. Generally, the conjugated enzyme to PSMA nanoparticles showed greater results than Ecoflex® nanoparticles. [ABSTRACT FROM AUTHOR]

Small-molecule drugs often have limited solubility, display rapid clearance or poor selectivity that leads to undesired side-effects. Although prodrug strategies can improve solubility and lower toxicity, activation 'on demand' as well as targeted transport of prodrugs remains a challenge in drug delivery. Responsive polymeric nanoparticles can help meet these challenges with the encapsulation or conjugation of drugs, allowing release at the target site upon triggering by an internal or external stimulus. The adaptable design of polymeric nanoparticles allows them to play a vital role in achieving a specific and desired response following application of a specific stimulus. Here, the most recent progress in responsive polymeric nanoparticles is reviewed with a focus on the chemical properties of the utilized polymers. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In vitro and in vivo behavior of nanoparticles (NPs) is often studied by tracing the NPs with fluorescent dyes. This requires stable incorporation of dyes within the NPs, as dye leakage may give a wrong interpretation of NP biodistribution, cellular uptake, and intracellular distribution. Furthermore, NP labeling with trace amounts of dye should not alter NP properties such as interactions with cells or tissues. To allow for versatile NP studies with a variety of fluorescence-based assays, labeling of NPs with different dyes is desirable. Hence, when new dyes are introduced, simple and fast screening methods to assess labeling stability and NP-cell interactions are needed. For this purpose, we have used a previously described generic flow cytometry assay; incubation of cells with NPs at 4 and 37°C. Cell-NP interaction is confirmed by cellular fluorescence after 37°C incubation, and NP-dye retention is confirmed when no cellular fluorescence is detected at 4°C. Three different NP-platforms labeled with six different dyes were screened, and a great variability in dye retention was observed. Surprisingly, incorporation of trace amounts of certain dyes was found to reduce or even inhibit NP uptake. This work highlights the importance of thoroughly evaluating every dye-NP combination before pursuing NP-based applications. © 2016 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Nanomedicine is one of the fastest growing areas of nanotechnology. The control over nanoparticle design and the ability to tailor nanoparticle performance to fit exacting requirements is anticipated to enhance the safety and efficacy of patient treatment. Within this space, molecular polymer brushes - single macromolecules of the size of colloids - offer a modular platform to precisely engineer nanoparticles with uniform size, shape and composition. In addition, this technology permits the compartmentalisation of chemical environments to produce multifunctional nanoparticles for tailored biomedical applications. This article highlights the recent developments in polymer brush nanoparticles for use in delivery and imaging applications. [ABSTRACT FROM AUTHOR]

Achieving optimal solubility of active substances in polymeric carriers is of fundamental importance for a number of industrial applications, including targeted drug delivery within the growing field of nanomedicine. However, its experimental optimization using a trial-and-error approach is cumbersome and time-consuming. Here, an approach based on molecular dynamics (MD) simulations and the Flory-Huggins theory is proposed for rapid prediction of thermodynamic compatibility between active species and copolymers comprising hydrophilic and hydrophobic segments. In contrast to similar methods, our approach offers high computational efficiency by employing MD simulations that avoid explicit consideration of the actual copolymer chains. The accuracy of the method is demonstrated for compatibility predictions between pyrene and nile red as model dyes as well as indomethacin as model drug and copolymers containing blocks of poly(ethylene glycol) and poly(lactic acid) in different ratios. The results of the simulations are directly verified by comparison with the observed encapsulation efficiency of nanoparticles prepared by nanoprecipitation. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Here, the formation of nanoparticles based on a microemulsion approach and the use of polymer surfactants are described. Therefore, two amphiphilic poly(2-oxazoline) block copolymers P1 and P2 with alkyne groups in their hydrophobic block have been synthesized by ring-opening, cationic polymerization. The polymers P1 and P2 are employed in a microemulsion process to stabilize the particle core by core cross-linking of 1,6-hexanediol diacrylate (HDDA) using either AIBN as azo-initiator or 2-propanethiol as a photo-initiator for the polymerization reaction. The results show that particle size can be controlled by sonication time, the hydrophilic-hydrophobic balance of the polymer surfactant, and the ratio of polymer surfactant versus HDDA giving access to water-soluble nanoparticles in a size range of 10-70 nm. [ABSTRACT FROM AUTHOR]

ABSTRACT The pH-sensitive tertiary amino groups were introduced to synthesize temperature and pH dual-sensitive degradable polyaspartamide derivatives (phe/DEAE-g-PHPA) containing pendant aromatic structures and ionizable tertiary amino groups. The thermo/pH-responsive behavior of phe/DEAE-g-PHPA polymer can be tuned by adjusting the graft copolymer composition. Due to the pH sensitivity of the phe/DEAE-g-PHPA-g-mPEG polymer with hydrophilic long PEG chain, the micelles and the anticancer drug-loaded micelles were prepared by a quick pH-changing method without using toxic organic solvent. The obtained polymeric micelles, paclitaxel-loaded micelles and doxorubicin-loaded micelles were stable under physiological conditions. Both the drug-loaded micelles showed much faster release at pH 5 than at pH 7.4. The doxorubicin-loaded micelles showed obvious and better anticancer activity against both HepG2 and HeLa cells than free doxorubicin. Thus these nontoxic, dual thermo- and pH-sensitive phe/DEAE-g-PHPA-g-mPEG micelles may be a promising anticancer drug delivery system. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 879-888 [ABSTRACT FROM AUTHOR]

The current contribution serves as a critical update to a previous feature article from us ( Macromol. Rapid Commun. 2012, 33, 958−971), and highlights the latest advances in the preparation of single chain polymeric nanoparticles and initial-yet promising-attempts towards mimicking the structure of natural biomacromolecules via single-chain folding of well-defined linear polymers via so-called single chain selective point folding and repeat unit folding. The contribution covers selected examples from the literature published up to ca. September 2015. Our aim is not to provide an exhaustive review but rather highlight a selection of new and exciting examples for single-chain folding based on advanced macromolecular precision chemistry. Initially, the discussion focuses on the synthesis and characterization of single-chain folded structures via selective point folding. The second part of the feature article addresses the folding of well-defined single-chain polymers by means of repeat unit folding. The current state of the art in the field of single-chain folding indicates that repeat unit folding-driven nanoparticle preparation is well-advanced, while initial encouraging steps towards building selective point folding systems have been taken. In addition, a summary of the-in our view-open key questions is provided that may guide future biomimetic design efforts. [ABSTRACT FROM AUTHOR]

Nanobiotechnology holds great potential in various regimes of life sciences. In this review, the potential applications of nanobiotechnology in various sectors of nanotechnologies, including nanomedicine and nanobiopharmaceuticals, are highlighted. To overcome the problems associated with drug delivery, nanotechnology has gained increasing interest in recent years. Nanosystems with different biological properties and compositions have been extensively investigated for drug delivery applications. Nanoparticles fabricated through various techniques have elevated therapeutic efficacy, provided stability to the drugs and proved capable of targeting the cells and controlled release inside the cell. Polymeric nanoparticles have shown increased development and usage in drug delivery as well as in diagnostics in recent decades. [ABSTRACT FROM AUTHOR]

Background Silencing of excessive secreted tumour necrosis factor (TNF)-α from macrophages might be an effective therapy of ulcerative colitis (UC), which acquires improvements on small interfering RNA (siRNA) delivery vectors. Thus, in the present study, the effects of particle size and binding affinity of four polymeric nanoparticles on siRNA delivery for the treatment of UC were evaluated. Methods Galactosylated trimethyl chitosan-cysteine (GTC) nanoparticles of varying particle size and binding affinity for siRNA were prepared and TNF-α siRNA was encapsulated. Their cellular transport was investigated in murine macrophages and Caco-2 cell monolayers were utilized to analysis the intestinal permeation. Finally, in vivo anti-inflammatory efficacy was assessed in a mouse model of UC. Results Although marginal effects of particle size on the in vitro gene silencing efficiency were detected, GTC nanoparticles with a particle size of 450nm and stronger binding affinity for siRNA showed reduced intestinal epithelial permeability and enhanced in vivo anti-inflammatory efficacy compared to those with a particle size of 200 nm. By contrast, the delivery processes were significantly affected by the binding affinity for siRNA, where smaller GTC nanoparticles (200 nm) with moderate siRNA binding strength exhibited remarkable cytoplasmic distribution and sufficient intracellular release of siRNA, as well as a sustained in vitro and in vivo gene silencing effect. Conclusions Nanoparticles with a particle size of 450 nm or balanced binding affinity for siRNA might be preferable for the treatment of ulcerative colitis. [ABSTRACT FROM AUTHOR]