Supramolecular anticancer drug delivery systems based on linear–dendritic copolymers

Current cancer chemotherapy often suffers severe side-effects of the administered cancer drugs on the normal tissues. In addition, poor bioavailability, due to the low water solubility of the anticancer drugs, limits their applications in chemotherapy. New delivery technologies could help overcome this challenge by improving the water solubility and achieving the targeted delivery of the anticancer drugs. Linear–dendritic hybrid nanomaterials, which combine the highly branched architectures and multifunctionality of dendrimers with the processability of traditional linear–linear block copolymers, have been introduced as ideal carriers in anticancer drug delivery applications. This review presents recent advances in the investigational aspects of linear–dendritic copolymers to be applied as anticancer drug delivery vehicles. We highlight the structures, synthesis of linear–dendritic block copolymers, interaction mechanisms between linear–dendritic copolymers and anticancer drug molecules, and findings on their drug release behavior and anticancer efficacies in vitro and in vivo

Synthesis, self-assembly, and photocrosslinking of fullerene-polyglycerol amphiphiles as nanocarriers with controlled transport properties

In this work, we report a new, simple, gram-scale method for synthesizing water-soluble fullerene-polyglycerol amphiphiles (FPAs) that self-assemble into partially and fully crosslinked nanoclusters with the ability to controllably transport hydrophobic and hydrophilic agents

Photoswitchable single-walled carbon nanotubes for super-resolution microscopy in the near-infrared

The design of single-molecule photoswitchable emitters was the first milestone toward the advent of single-molecule localization microscopy, setting a new paradigm in the field of optical imaging. Several photoswitchable emitters have been developed, but they all fluoresce in the visible or far-red ranges, missing the desirable near-infrared window where biological tissues are most transparent. Moreover, photocontrol of individual emitters in the near-infrared would be highly desirable for elementary optical molecular switches or information storage elements since most communication data transfer protocols are established in this spectral range. Here, we introduce a type of hybrid nanomaterials consisting of single-wall carbon nanotubes covalently functionalized with photoswitching molecules that are used to control the intrinsic luminescence of the single nanotubes in the near-infrared (beyond 1 μm). Through the control of photoswitching, we demonstrate super-localization imaging of nanotubes unresolved by diffraction-limited microscopy

Effects of biological fertilizers and sulfur on the quantitative and qualitative traits of cultivated shallot (Allium altissimum Regal) and comparison of these traits with those ones in the natural habitat

The present study was conducted aiming at the protection of the shallot (Allium altissimum Regal) in natural habitat, which is endangered due to excessive harvesting. In order to increase the sustainability of this product, its wild ecotypes were planted in agricultural land and the effect of bio-fertilizers (nitroxin and phosphate) and sulfur on quantitative (yield and yield components) and qualitative (the active ingredient, allicin, crude protein, and the amount of phosphorus and potassium) traits were investigated. The results showed that the amount of allicin, crude protein, phosphorus, potassium, and yield in the planted ecotypes were significantly higher than the wild type in the studied natural habitat. The results of this study indicated a significant difference respecting quantitative and qualitative trait of cultivated shallot with proper nutritional management compared to wild shallot. Therefore, the expansion and development of this method can lead to the sustainability of the production of shallot and will conserve diversity of its populations in natural habitat

Two-Dimensional Triazine Polymers as Recyclable Fluorescent Sensors to Detect and Remove Sub-nanomolar Hg(II) From Water

In this work, full triazine two-dimensional frameworks (2DC3N3) were synthesized and used to detect metal ions in aqueous solutions. 2DC3N3 showed excellent performance to sense Hg(II) with high selectivity (>96%) and was designed as a recyclable sensor for Hg(II) detection. 2DC3N3 was synthesized using catalyst-free [2+2+2] cyclotrimerization of sodium cyanide and cyanuric chloride at ambient conditions. The as-prepared 2DC3N3 sheets with several hundred micrometers lateral size exhibited strong excitation-dependent fluorescence with 63% quantum yield and maximum emission at 428 nm. The emission of 2DC3N3 decreased with 14.74 × 103 L·mol–1 quenching constant (KSV) upon interaction with Hg2+ ions. This effect was used as a strong signal to detect Hg(II) with a 0.98 nM detection limit. The high Hg2+ removal capacity of 2DC3N3 was attributed to cooperative interactions of nitrogen atoms of 2DC3N3 pores and Hg2+, as suggested by computational studies. Taking advantage of the straightforward synthesis of 2DC3N3 and its selectivity, it can be used as an efficient platform for monitoring Hg2+ in waste and drinking water

Fluorescent Polymer—Single‐Walled Carbon Nanotube Complexes with Charged and Noncharged Dendronized Perylene Bisimides for Bioimaging Studies

Fluorescent nanomaterials are expected to revolutionize medical diagnostic, imaging, and therapeutic tools due to their superior optical and structural properties. Their inefficient water solubility, cell permeability, biodistribution, and high toxicity, however, limit the full potential of their application. To overcome these obstacles, a water‐soluble, fluorescent, cytocompatible polymer—single‐walled carbon nanotube (SWNT) complex is introduced for bioimaging applications. The supramolecular complex consists of an alkylated polymer conjugated with neutral hydroxylated or charged sulfated dendronized perylene bisimides (PBIs) and SWNTs as a general immobilization platform. The polymer backbone solubilizes the SWNTs, decorates them with fluorescent PBIs, and strongly improves their cytocompatibility by wrapping around the SWNT scaffold. In photophysical measurements and biological in vitro studies, sulfated complexes exhibit superior optical properties, cellular uptake, and intracellular staining over their hydroxylated analogs. A toxicity assay confirms the highly improved cytocompatibility of the polymer‐wrapped SWNTs toward surfactant‐solubilized SWNTs. In microscopy studies the complexes allow for the direct imaging of the SWNTs' cellular uptake via the PBI and SWNT emission using the 1st and 2nd optical window for bioimaging. These findings render the polymer‐SWNT complexes with nanometer size, dual fluorescence, multiple charges, and high cytocompatibility as valuable systems for a broad range of fluorescence bioimaging studies

Tailoring topology and bio-interactions of triazine frameworks

The construction of covalent organic frameworks with special geometery and optical properties is of high interest, due to their unique physicochemical and biological properties. In this work, we report on a new method for the construction of triazine frameworks with defined topologies using coordination chemistry. Ball milling and wet chemical reactions between cyanuric chloride and melamine were directed in spatial arrangements and opposite optical activity. Cobalt was used as a directing agent to drive reactions into special morphologies, optical properties and biological activity. The enantiorecognition ability of triazine frameworks that was manifested in their activities against bacteria, demonstrated a new way for the construction of materials with specific interactions at biointerfaces

Thermoresponsive and antibacterial two-dimensional polyglycerol-interlocked-polynipam for targeted drug delivery

Two-dimensional polymeric networks are a new class of polymers with interesting physicochemical and biological properties. They promise a wide range of future biomedical applications including pathogen interactions, drug delivery, bioimaging, photothermal, and photodynamic therapy, owing to their unique features, such as high surface area and multivalent interactions at nano-biointerfaces. In this work, a thermosensitive two-dimensional polymeric network consisting poly(N-isopropylacrylamide) (pNIPAM) chains that are mechanically interlocked by a polyglycerol platform was synthesized and used for bacteria incapacitation. Two-dimensional hyperbranched polyglycerol (2D-hPG) was synthesized by a graphene-assisted strategy and used for encapsulation of azobisisobutyronitrile (AIBN). Radical polymerization of N-isopropylacrylamide by encapsulated AIBN resulted in thermoresponsive platforms with ~ 500 nm lateral size and 20–50 nm thickness. Due to its porous structure, 2D-PNPG was able to efficiently load antibiotics, such as tetracycline (TC) and amoxicillin (AMX). The rate of release of antibiotics from 2D-PNPG and the antibacterial activity of the system correlated with the variation of temperature as a result of the thermosensitivity of 2D-PNPG. This study shows that two-dimensional polymers are efficient platforms for future biomedical applications including drug delivery and bacteria incapacitation

Synthesis of a Poly(glycerol-sulfur) Network as a Sustainable Adsorbent for Positively Charged Dyes from Aqueous Solutions

Textile and industrial dyes, which are among the most prominent organic compounds, pose a range of health risks and require efficient treatment before being released into the environment. In this study, a polymeric network was synthesized through the cationic ring-opening copolymerization of glycerol and elemental sulfur, both byproducts of the biodiesel and oil industries. This network was then used as an adsorbent for the cationic dyes. The structure and composition of the synthesized poly(glycerol-sulfur) (PG-S) were characterized by using various spectroscopy methods along with elemental and thermal analysis. PG-S exhibited thermal stability up to 450 °C, an average pore size of 4.6 nm, and a surface area of 88.7 m2/g. Solid-state NMR spectra revealed a distinct C–S signal, which confirmed the successful synthesis of the composite. PG-S demonstrated excellent potential for removing industrial dyes from contaminated water. We investigated various parameters, including initial dye concentration, adsorption time, pH, adsorbent quantity and size, and temperature, to better understand the dye adsorption mechanism. The results showed that PG-S efficiently removed Janus Green (JG) and Crystal Violet (CV) from water in a selective manner. The maximum adsorption capacities were observed within the pH range of 6–12, with values of 267 mg g–1 for JG and 226 mg g–1 for CV. These values remained unchanged after 10 cycles of recycling. Given its straightforward synthesis and exceptional physicochemical properties, such as a high adsorption capacity, this polymeric network is a promising candidate for dye removal and water treatment applications