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In the recent years, electroconductive scaffolds have shown promising capabilities in guided regeneration of electroactive tissues including nerve, heart muscle, bone, cartilage, and skin. Herein, the fabrication of a novel electroconductive poly (L‐lactic acid) (PLLA)/polyamidoamine (PAMAM) dendrimer nanofibrous scaffold containing graphene oxide (GO) nanosheets is described. The presence of PAMAM with amine terminal groups successfully aminolyzed PLLA. Interestingly, both PAMAM (5% w/w) and GO (0.5, 1, 2% w/w) not only contributed to reducing the fiber diameter, increasing the hydrophilicity and degradation rate, but also provided a nanocomposite scaffold with enhancement in electrical conductivity. By incorporating 1% w/w of GO, the nanocomposite scaffold exhibited optimized properties, including electrical conductivity (≈3.09 × 10−5 S m−1), crystallinity (≈ 47%), Young's modulus (≈16.95 MPa), as well as strength (≈1.58 MPa). This nanocomposite also demonstrated significant antibacterial activity of ≥ 90% against both gram‐positive and gram‐negative bacteria. Cellular assays confirmed acceptable cytocompatibility of the nanocomposite scaffolds containing GO and PAMAM, which can support the viability and proliferation of PC‐12 cells. In conclusion, the presence of GO nanosheets alongside PAMAM dendrimers can synergically promote the properties of the prepared nanofibrous mats which can be used as potential electroconductive scaffolds for guided tissue regeneration. [ABSTRACT FROM AUTHOR]

Fluorescent dyes, or fluorophores, enable researchers to visualize specific biological molecules by fluorescence microscopy. Herein, a novel fluorescent FITC-poly(amidoamine) (FITC-PAMAM) dendrimers have been synthesized via divergent approach. The molecular structure of the FITC-PAMAM dendrimers (G-0 to G5) was characterized by 1H NMR, 13C NMR spectroscopy and by FTIR. In order to emphasize the structural efficacy of FITC-PAMAM dendrimer, the drug delivery behavior has been evaluated by using 5-fluorouracil (5-FU) as a model cancer therapy drug. Anti-proliferative activity of FITC-cored PAMAM dendrimers in all generations (G0-G5) with or without 5-FU were analyzed on human gastric carcinoma cells (AGS) by WST-1 cell proliferation assay. Initially, the nontoxic dose of unloaded FITC-PAMAM dendrimers was assessed for further drug loading experiments. Loading of 5-FU into FITC-PAMAM dendrimers, regardless of generation, increased the toxicity of the drug. Besides, 5-FU loaded FITC-PAMAM dendrimers induced a generation-based gradual inhibition of cell proliferation. FITC and phase contrast merged images indicated that FITC-PAMAM dendrimers facilitate the entry of the drug into the cells, in a generation-dependent manner. The FITC- dendrimers may serve as a promising intracellular drug delivery agent for 5-FU by increasing cell uptake into cells and thereby, enhancing antiproliferative activity on AGS cells in a generation-dependent manner. [ABSTRACT FROM AUTHOR]

Abstract In the recent years, electroconductive scaffolds have shown promising capabilities in guided regeneration of electroactive tissues including nerve, heart muscle, bone, cartilage, and skin. Herein, the fabrication of a novel electroconductive poly (L‐lactic acid) (PLLA)/polyamidoamine (PAMAM) dendrimer nanofibrous scaffold containing graphene oxide (GO) nanosheets is described. The presence of PAMAM with amine terminal groups successfully aminolyzed PLLA. Interestingly, both PAMAM (5% w/w) and GO (0.5, 1, 2% w/w) not only contributed to reducing the fiber diameter, increasing the hydrophilicity and degradation rate, but also provided a nanocomposite scaffold with enhancement in electrical conductivity. By incorporating 1% w/w of GO, the nanocomposite scaffold exhibited optimized properties, including electrical conductivity (≈3.09 × 10−5 S m−1), crystallinity (≈ 47%), Young's modulus (≈16.95 MPa), as well as strength (≈1.58 MPa). This nanocomposite also demonstrated significant antibacterial activity of ≥ 90% against both gram‐positive and gram‐negative bacteria. Cellular assays confirmed acceptable cytocompatibility of the nanocomposite scaffolds containing GO and PAMAM, which can support the viability and proliferation of PC‐12 cells. In conclusion, the presence of GO nanosheets alongside PAMAM dendrimers can synergically promote the properties of the prepared nanofibrous mats which can be used as potential electroconductive scaffolds for guided tissue regeneration.

Six differently charged amphoteric polyamidoamines, synthesized by the polyaddition of N,N′-methylenebisacrylamide to alanine, leucine, serine, arginine (M-ARG), glutamic acid (M-GLU) and a glycine/cystine mixture, were screened for their short-term phytotoxicity using a seed germination test. Lepidium sativum L. seeds were incubated in polyamidoamine water solutions with concentrations ranging from 0.156 to 2.5 mg mL−1 at 25 ± 1 °C for 120 h. The seed germination percentage (SG%), an indicator of acute toxicity, and both root and shoot elongation, related to plant maturation, were the considered endpoints. The germination index (GI) was calculated as the product of relative seed germination times relative radical growth. The SG% values were in all cases comparable to those obtained in water, indicating no detectable acute phytotoxicity of the polyamidoamines. In the short term, the predominantly positively charged M-ARG proved to be phytotoxic at all concentrations (GI < 0.8), whereas the predominantly negatively charged M-GLU proved to be biostimulating at intermediate concentrations (GI > 1) and slightly inhibitory at 2.5 mg mL−1 (0.8 < GI < 1). Overall, polyamidoamine phytotoxicity could be correlated to charge distribution, demonstrating the potential of the test for predicting and interpreting the eco-toxicological behavior of water-soluble polyelectrolytes. [ABSTRACT FROM AUTHOR]

Indole‐3‐acetic acid (IAA) assumes a pivotal role as a phytohormone of utmost importance, intricately orchestrating the nuanced processes associated with the growth and developmental trajectories of botanical organisms. In this study, we have designed and fabricated a label‐free electrochemical impedance immunosensor for the precise detection of IAA. The detection strategy predominantly relied upon polydopamine modified carbon nitride (C3N4) nanosheets (PCN) and polyamidoamine (PAMAM) dendrimer. Through the modification with PCN and PAMAM, the electrode has increased the active area and enhanced the immobilization capacity of antibodies for IAA. The immunosensor's ability to capture IAA was significantly improved by enhancing the immunoreaction between the antibody and antigen. This enhancement led to an increased response in the electrochemical behavior of the Fe(CN)63−/4− redox probe. The impedance immunosensor developed exhibits remarkable sensitivity, exceptional selectivity, and consistent performance in the detection of IAA. This assay method, with the potential to replace antibodies, could offer an alternative approach for detecting various phytohormones. [ABSTRACT FROM AUTHOR]

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In an attempt to produce bio-composites that possess good physico-mechanical properties, polyamidoamine (PAMAM) was synthesized and characterized as a multi-nitrogen terminal biocompatible and nontoxic polymeric species. It was mixed at various ratios of 1.0, 2.0, and 3.0% with polypropylene (PP) via Brabender-like apparatus. The prepared bio-composites were exposed to 20 kGy of gamma-irradiation to investigate the influence of ionizing radiation on the fabricated specimens. Parameters of mechanical for instance tensile strength (TS), modulus of elasticity (EM), elongation at break (%), and hardness (Shore D), of bio-composites, were considered. Moreover, the stress-strain curves of the fabricated samples were investigated. Furthermore, FTIR and thermal analysis including TGA and DSC have been investigated. The crystallinity % of all investigated samples was calculated on the basis of DSC measurements. Overall migration of prepared samples has been performed as an applicable study of food packaging. FTIR results revealed the disappearance of the absorption peak at 1730 cm−l of the carbonyl group of polyamidoamine after the formation of PP/PAMAM bio-composites, indicating a successful combination of the PP matrix with polyamidoamine. The incorporation of PAMAM resulted in a steady improvement of the melting temperature (Tm) of the native PP. The thermal stability of PP/PAMAM composition increases with increasing PAMAM and after being exposed to 20 kGy irradiation. Mechanical data revealed that TS of PP increased with PAMAM content up to 3.0%. The development in TS increased from 20 MPa of native PP to 45 MPa of PP/2% PAMAM bio-composites suggesting the superior interaction between the synthetic PAMAM and PP texture. Furthermore, the prepared bio-composite films displayed highly acceptable migration limits. Graphical Abstract [ABSTRACT FROM AUTHOR]

In this research, a catalytic system using a copper complex supported on silica nanoparticles was used as a nanocatalyst with high efficiency to enhance catalytic click reactions. At first, polyamidoamine dendrimers were synthesized using methyl acrylate and ethylene diamine by divergent synthesis method on aminopropyl grafted silica support. Then, modified silica-supported dendrimers were used as an organic-inorganic hybrid substrate to immobilize the NNN pincer ligand. The pincer ligand was formed by reacting the functionalized support with cyanuric chloride and then reacting with 2-aminopyridine. Next, through the reaction of copper chloride with the stabilized ligand, the copper (II) complex was formed on this compound. The prepared compound was used as a catalyst in azide-alkyne cycloaddition click reactions. The obtained data showed that in the optimized conditions: water-ethanol solution (1:1), catalyst mole percentage of 0.5, 60 °C, and time of 40 min, the reaction efficiency was obtained to be 97%. [ABSTRACT FROM AUTHOR]

Abstract Indole‐3‐acetic acid (IAA) assumes a pivotal role as a phytohormone of utmost importance, intricately orchestrating the nuanced processes associated with the growth and developmental trajectories of botanical organisms. In this study, we have designed and fabricated a label‐free electrochemical impedance immunosensor for the precise detection of IAA. The detection strategy predominantly relied upon polydopamine modified carbon nitride (C3N4) nanosheets (PCN) and polyamidoamine (PAMAM) dendrimer. Through the modification with PCN and PAMAM, the electrode has increased the active area and enhanced the immobilization capacity of antibodies for IAA. The immunosensor‘s ability to capture IAA was significantly improved by enhancing the immunoreaction between the antibody and antigen. This enhancement led to an increased response in the electrochemical behavior of the Fe(CN)63−/4− redox probe. The impedance immunosensor developed exhibits remarkable sensitivity, exceptional selectivity, and consistent performance in the detection of IAA. This assay method, with the potential to replace antibodies, could offer an alternative approach for detecting various phytohormones.

In order to achieve the benefits of targeted drug delivery, this study intended to encapsulate doxorubicin in a linear polyamidoamine and its PEGylated co-polymer. The drug was loaded by using the emulsion solvent evaporation method. By adjusting the doxorubicin to polymer ratios to 1:10, 1:20 and 1:30, three formulations of each polymer/copolymer were prepared. The drug release profile was investigated using phosphate buffered saline. In vitro cytotoxicity investigation was executed on liver cancer cell line (Hep G2 cell lines) by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay. The outcome demonstrated that doxorubicin had been successfully loaded on polyamidoamine and its PEGylated co-polymer with a drug loading efficiency of about 90%. Nanocarrier sizes were between 245±1.10 nm -579±1.00 nm and the zeta potential range was +22.4±0.5 mV-+37.9±0.3 mV. In-vitro drug release investigations revealed a characteristic pH-dependent drug release. The cytotoxicity testing of optimal formulation revealed that the doxorubicin was successfully released from the formulations and exerted therapeutic effect. According to our research, doxorubicin could be loaded onto linear polyamidoamines for potent antitumor effects on the target liver cancer cell lines (Hep G2). [ABSTRACT FROM AUTHOR]

Multifactor‐responsive nanomaterials have been playing a vital role in drug delivery developments. Given the advantages of nanotechnology‐based systems, employing stimuli‐sensitive agents could offer a step forward to targeted drug delivery. Hence, we targeted to apply both thermal and redox‐sensitive agents, which are poly(N‐isopropylacrylamide) (PNIPAM) and disulfide, onto a classic platform polyamidoamine (PAMAM) dendrimer. In particular, PAMAM G3.5 was first grafted by an outermost layer composed of cystamine moieties and partially grafted with PNIPAM segments. This novel nanomaterial was successfully verified by FTIR, 1H NMR, and Raman spectroscopy. Besides, morphological and surface characteristics were observed by DLS, TEM, and zeta potential. Our novel drug delivery system displayed a spherical shape with a hydrodynamic size of 43.61 ± 6.04 nm at 37°C and 68.99 ± 4.69 nm at 15°C, which proved its thermoresponsiveness. In parallel, the response of the nanoparticles toward redox concentration variation was testified that demonstrated a controlled drug release highly depending on physiological stimuli. We have also conducted in vitro DOX release and cytocompatibility of this drug delivery system, which can premise a smart strategy for nanoengineering in targeted drug delivery for cancer therapy. [ABSTRACT FROM AUTHOR]

One of the most severe health diseases affect the mankind is cancer. The treatment methods such as magnetic hyperthermia, chemotherapy, photothermal therapy and MRI‐traced cancer drug delivery system have been available for cancer treatment. The prime of cancer treatment is Chemotherapy but it has not proved the proper satisfaction due to the resistance developed in the tumour. Now‐a‐days, dendrimers are the most important and powerful drug carriers in the anticancer applications. The polyamidoamine (PAMAM) dendrimers have played wider role and the addition of nanomaterials in polyamidoamine dendrimer provided great results in the anticancer properties and medicinal applications. In recent years, researchers have interested to undergo investigation on dendrimer supported nanomaterials due to the outstanding experimental results against the cancer cells. Therefore, the main goal of the article is to deliberate the comprehensive overview of the properties, anticancer applications of the nanomaterials supported dendrimer as the nanocarrier for the anticancer applications. [ABSTRACT FROM AUTHOR]

Polyamidoamine hydrogels prepared by the radical post-polymerization of α,ω-bisacrylamide-terminated M-AGM oligomers, in turn obtained by the polyaddition of 4-aminobutylguanidine with N,N'-methylenebisacrylamide, were reinforced with raw silk fibers, which can establish covalent bonds with the polyamidoamine matrix via reaction of the amine groups in the lysine residues with the acrylamide terminals of the M-AGM oligomer. Silk/M-AGM membranes were prepared by impregnating silk mats with M-AGM aqueous solutions and subsequent crosslinking by UV irradiation. The guanidine pendants of the M-AGM units imparted the ability to form strong but reversible interactions with oxyanions, including the highly toxic chromate ions. The potential of the silk/M-AGM membranes to purify Cr(VI)-contaminated water down to the drinkability level, that is, below 50 ppb, was tested by performing sorption experiments both in static (Cr(VI) concentration 20–2.5 ppm) and flow conditions (Cr(VI) concentration 10–1 ppm). After static sorption experiments, the Cr(VI)-loaded silk/M-AGM membranes could easily be regenerated via treatment with a 1 M sodium hydroxide solution. Dynamic tests performed using two stacked membranes and a 1 ppm Cr(VI) aqueous solution reduced Cr(VI) concentration down to 4 ppb. Remarkably, the use of renewable sources, the environmentally friendly preparation process, and the goal achieved meet eco-design requirements. [ABSTRACT FROM AUTHOR]

To prepare polymer-drug conjugates containing a combination of memantine, tacrine, and E)-N-(3-aminopropyl)cinnamide, promising therapeutics for the treatment of neurodegenerative disorders. The conjugates were characterised by 1HNMR, particle size analysis, SEM, LC-MS, TEM/EDX, and XRD, followed by in vitro anti-acetylcholinesterase and drug release studies. 1H NMR analysis revealed successful drug conjugation with drug mass percentages in the range of 1.3–6.0% w/w. The drug release from the conjugates was sustained for 10 h in the range of 20–36%. The conjugates' capability to inhibit acetylcholinesterase (AChE) activity was significant with IC50 values in the range of 13–44.4 µm which was more effective than tacrine (IC50 =1698.8 µm). The docking studies further confirmed that the conjugation of the drugs into the polymer improved their anti-acetylcholinesterase activity. The drug release profile, particle sizes, and in vitro studies revealed that the conjugates are promising therapeutics for treating neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chitosan/poly(vinyl alcohol)/graphene oxide (GO) hydrogels were prepared. • The controlled release of CFX was estimated. • Highest swelling was demonstrated by one of the samples (CAB-1). • Biodegradability in phosphate PBS and proteinase-K solution were demonstrated. The controlled and targeted release is a major challenge for the researchers in order to maintain bioavailability of drugs without leaving physicochemical side effects. Almost 50 % of cefixime (CFX) is eliminated via urinary route due to its poor bioavailability. Therefore, in the present work, chitosan/poly(vinyl alcohol)/graphene oxide (GO) hydrogels were prepared by varying the amount of polyamidoamine (PAMAM) for the controlled CFX release. Fourier transform infrared spectroscopy, thermo-gravimetric analysis and scanning electron microscope were used to determine binding patterns, thermal stabilities, and surface morphologies respectively. Cell viability assessment revealed the improved cytocompatibility against HEK-293 cells. In distilled water, the highest swelling (46056 %) was demonstrated by CAB-1 and non-Fickian diffusion model was followed. In addition, all the hydrogels demonstrated maximum swelling at pH 4. PAMAM imparted thermal and bio-degradational stabilities. By the increase in concentration of PAMAM, swelling % and bactericidal activities vs. Escherichia coli and Psuedomonas aeruginosa were decreased. The hydrogels demonstrated biodegradability in phosphate buffer saline (PBS) and proteinase-K solution. The CFX release was determined by UV–Visible spectrophotometer. In 8.5 h, 84.98 % and 80.14 % of CFX was released in simulated gastric fluid and PBS solution, respectively. The chitosan-based hydrogel frameworks presented biocompatible, biodegradable, and cytocompatible platform for drug delivery and other medico-biological applications. [ABSTRACT FROM AUTHOR]

An amine-terminated polyamidoamine (PAMAM) dendron and two long alkyl groups were designed as a novel drug carrier that possesses an interior for the encapsulation of drugs and a biocompatible surface. We synthesized three dendron-bearing lipids, DL-G1, DL-G2, and DL-G3, which included first, second, and third generation polyamidoamine dendrons, respectively. The synthesized dendrimer encapsulating anticancer drug, 5-fluorouracil (5-FU), was prepared by extraction with chloroform from mixtures of the dendrimers and varying amounts of the drug. In vitro cytotoxicity of PAMAM conjugated di-n-dodecylamine micelles (G1, G2, G3) were analyzed on human gastric adenocarcinoma cells (AGS) by water-soluble tetrazolium-1 (WST-1) cell proliferation assay. Upon exposure to 5-FU loaded micelles, the viability of the cells decreased gradually in all generations. Cytotoxicity increased with increasing generation and reached its highest rate of 69.8 ± 3.2% upon 15 µM 5FU-loaded 25 µM PAMAM DL-3 micelle treatment. These results demonstrate that 5FU-loaded PAMAM conjugated di-n-dodecylamine treatment inhibits the proliferation of AGS cells in a generation-dependent manner. [ABSTRACT FROM AUTHOR]

Linear amphoteric polyamidoamines (PAAs) are usually water-soluble, biodegradable and biocompatible. Crosslinked PAAs form in water hydrogels, retaining most of the favorable properties of their linear counterparts. The hydrogels prepared by the radical post-polymerization of the oligo-α,ω-bisacrylamido-terminated PAA called AGMA1, obtained by the polyaddition of 4-aminobutylguanidine (agmatine) with 2,2-bis(acrylamido)acetic acid, exhibit excellent cell-adhesion properties both in vitro and in vivo. However, due to their low mechanical strength, AGMA1 hydrogels cannot be sewn to biological tissues and need to be reinforced with fibrous materials. In this work, short silk fibers gave excellent results in this sense, proving capable of establishing covalent bonds with the PAA matrix, thanks to their lysine content, which provided amino groups capable of reacting with the terminal acrylamide groups of the AGMA1 precursor in the final crosslinking phase. Morphological analyses demonstrated that the AGMA1 matrix was intimately interconnected and adherent to the silk fibers, with neither visible holes nor empty volumes. The silk/H-AGMA1 composites were still reversibly swellable in water. In the swollen state, they could be sewn and showed no detachment between fibers and matrix and exhibited significantly improved mechanical properties compared with the plain hydrogels, particularly as regards their Young's modulus and elongation at break. [ABSTRACT FROM AUTHOR]

Gu Gong,1,&ast; Xiuhui Tang,2,&ast; Jiayuan Zhang,2 Xiao Liang,2 Jiebing Yang,2 Quanshun Li2 1Department of Orthopaedic Surgery, China-Japan Union Hospital, Jilin University, Changchun, 130031, People’s Republic of China; 2Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun, 130012, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Quanshun Li; Jiebing Yang Tel/Fax +86-431-85155200Email quanshun@jlu.edu.cn; yangjiebing@lntu.edu.cnBackground: The construction of tumor-targeting carriers with favorable transfection efficiency was of great significance to achieve the tumor gene therapy. The phenylboronic acid-modified polyamidoamine (namely PP) was employed as a carrier for the delivery of Polo-like kinase-1 siRNA (siPlk-1), inducing an obvious anti-tumor response.Materials and Methods: The interaction between PP and siPlk-1 was evaluated by gel retardation assay. The transfection efficiency and tumor-targeting ability were analyzed by flow cytometry and confocal laser scanning microscopy, using hepatocarcinoma cell line HepG2 as a model. The anti-proliferation effect of PP/siPlk-1 and related mechanism were studied using the strategies of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell apoptosis and cell cycle arrest. The anti-migration effect induced by PP/siPlk-1 delivery was assayed by wound healing and Transwell migration techniques. Finally, quantitative real-time PCR and Western blotting were performed to measure the expression level of Plk-1 and other key targets.Results: The derivative PP could achieve the condensation of siPlk-1 into stable nanoparticles at nitrogen/phosphate groups ratio (N/P ratio) of > 3.0, and it could facilitate the transfection of siPk-1 in a phenylboronic acid-dependent manner. The PP/siPlk-1 nanoparticles exhibited obvious anti-proliferation effect owing to the gene silence of Plk-1, which was identified to be associated with the cell apoptosis and cell cycle arrest at G2 phase. Meanwhile, PP/siPlk-1 transfection could efficiently suppress the migration and invasion of tumor cells.Conclusion: The derivative PP has been demonstrated to be an ideal tumor-targeting carrier for the delivery of Plk-1 siRNA, exhibiting great potential in the gene therapy of malignant tumors.Keywords: phenylboronic acid, polyamidoamine, tumor-targeting ability, siPlk-1, gene therapy

Radiotherapy is essential for treating unresectable or metastatic breast cancer, but radiotherapy‐induced tumor cell death generates small extracellular vesicles (sEVs) that promote tumor regrowth and metastasis following treatment. Here cationic nanosheets with a high sEVs‐binding capacity that suppress sEVs‐induced tumor regrowth and metastasis following radiotherapy is developed. Molybdenum disulfide (MoS2) monolayers are prepared by using lithium ions as intercalation agents, and are functionalized with cationic polyamidoamine (PAMAM) dendrimers. The MoS2‐PAMAM particles exhibit a corrugated sheet‐like nanostructure with a larger surface‐to‐volume ratio than spherical PAMAM‐functionalized particles, resulting in greater sEVs binding capacity. Treatment of MDA‐MB‐231 human breast cancer cells with the MoS2‐PAMAM nanosheets reduces sEVs‐induced Toll‐like receptor activation and tumor cell proliferation, migration, and invasion to a greater extent than treatment with spherical PAMAM nanoparticles. In a mouse 4T1 metastatic breast cancer model, the nanosheets exhibit greater inhibition of tumor regrowth and metastasis after radiotherapy than the spherical nanoparticles, demonstrating the potential of these sEVs‐scavenging nanosheets for improving outcomes for breast cancer radiotherapy patients. The work reveals a pivotal role of the 2D sheet‐like materials in binding sEVs, indicating the significance of nanoscale geometry in developing the next‐generation sEVs‐scavenging biomaterials. [ABSTRACT FROM AUTHOR]

Cr(VI) is a toxic heavy metal ion, which can cause serious hazards to human health. The present study explored that polyamidoamine (PAMAM) dendrimer polycondensate was a potential promising adsorbent for removal of Cr(VI) from aqueous solution. The surface morphology of PAMAM dendrimer polycondensate was characterized by SEM. The adsorption capacity of Cr(VI) onto PAMAM dendrimer polycondensate was found to be dependent on Cr(VI) initial concentration, pH value of aqueous solution, adsorbent dosage, adsorption time, and adsorption temperature. In addition, the adsorption equilibrium could be described by Langmuir isotherm, Freundlich isotherm, and Temkin isotherm. The kinetic of the adsorption process is fitted with pseudo-second-order model and intraparticle diffusion model. The thermodynamic study showed that a negative value of ΔGθ indicated that the adsorption process was spontaneous in nature, while positive value of ΔHθ indicate that the adsorption is endothermic and higher temperature makes the adsorption easier, and positive value of ΔSθ reflected good affinity of Cr(VI) toward PAMAM dendrimer polycondensate. [ABSTRACT FROM AUTHOR]

Dendrimers are highly branched macromolecules tailorable at will to fulfil precise requirements. They have generated a great many expectations and a huge number of publications and patents in relation to medicine, including in relation to personalized medicine, but have resulted in very poor clinical translation up to now. As clinical trials are the first steps in view of developing new compounds for (a personalized) medicine, this review focusses on the clinical trials carried out with dendrimers. Many of these clinical trials have been recently posted (2020–2022); thus, only very few concern phase 3. The safety and efficiency of essentially two main types of dendrimers, based on polylysine and polyamidoamide scaffolds, have been assessed up to now. These dendrimers were tested with the aim of treating mainly bacterial vaginosis, cancers, and COVID-19. [ABSTRACT FROM AUTHOR]

The health and environmental concerns drive the exploration of electro‐optical materials featuring aqueous processability and environmental friendliness. This work presents a water‐soluble electroactive hyperbranched polyamidoamine toward electrochromic (EC)/electrofluorochromic (EFC) dual‐mode aqueous phase devices. The resultant polymer bearing viologen groups exhibit reversible electroactivity and desirable EC properties (ΔT% = 71.7%, coloration efficiency (CE) = 216 cm2 C−1). The aggregation‐induced quenching as well as the energy transfer between the electroactive viologen groups and autofluorescent tertiary amine units results in a simultaneous EFC behavior with acceptable fluorescence contrast (on/off = 8.5) and moderate switching speed (22.9/12.5 s). Furthermore, a reflective/emissive dual‐mode aqueous phase device is manufactured readily based on the resultant polymer, which displays a simultaneous EC and EFC performance with high optical contrast (ΔT% = 92%), moderate fluorescence contrast (4.5), competitive CE (108 cm2 C−1), and low switching voltage of −1.4 V. [ABSTRACT FROM AUTHOR]

Yang J, Zhang J, Xing J, Shi Z, Han H, Li Q. Int J Nanomedicine. 2019;14:6371– 6385. The authors have advised that during the assembly of subfigures in the preparation stage of the manuscript, two images in each of the Figure S8 and Figure S9 were duplicated. On page 6380, supplementary Figure S8, image Calcein-AM, Dz13 and Calcein-AM, PP/Dz13 were duplicated. On page 6380, supplementary Figure S9, images a and b were duplicated. Read the original article

Linear amphoteric polyamidoamines (PAAs) are usually water-soluble, biodegradable and biocompatible. Crosslinked PAAs form in water hydrogels, retaining most of the favorable properties of their linear counterparts. The hydrogels prepared by the radical post-polymerization of the oligo-α,ω-bisacrylamido-terminated PAA called AGMA1, obtained by the polyaddition of 4-aminobutylguanidine (agmatine) with 2,2-bis(acrylamido)acetic acid, exhibit excellent cell-adhesion properties both in vitro and in vivo. However, due to their low mechanical strength, AGMA1 hydrogels cannot be sewn to biological tissues and need to be reinforced with fibrous materials. In this work, short silk fibers gave excellent results in this sense, proving capable of establishing covalent bonds with the PAA matrix, thanks to their lysine content, which provided amino groups capable of reacting with the terminal acrylamide groups of the AGMA1 precursor in the final crosslinking phase. Morphological analyses demonstrated that the AGMA1 matrix was intimately interconnected and adherent to the silk fibers, with neither visible holes nor empty volumes. The silk/H-AGMA1 composites were still reversibly swellable in water. In the swollen state, they could be sewn and showed no detachment between fibers and matrix and exhibited significantly improved mechanical properties compared with the plain hydrogels, particularly as regards their Young’s modulus and elongation at break.

An amine-terminated polyamidoamine (PAMAM) dendron and two long alkyl groups were designed as a novel drug carrier that possesses an interior for the encapsulation of drugs and a biocompatible surface. We synthesized three dendron-bearing lipids, DL-G1, DL-G2, and DL-G3, which included first, second, and third generation polyamidoamine dendrons, respectively. The synthesized dendrimer encapsulating anticancer drug, 5-fluorouracil (5-FU), was prepared by extraction with chloroform from mixtures of the dendrimers and varying amounts of the drug. In vitro cytotoxicity of PAMAM conjugated di-n-dodecylamine micelles (G1, G2, G3) were analyzed on human gastric adenocarcinoma cells (AGS) by water-soluble tetrazolium-1 (WST-1) cell proliferation assay. Upon exposure to 5-FU loaded micelles, the viability of the cells decreased gradually in all generations. Cytotoxicity increased with increasing generation and reached its highest rate of 69.8 ± 3.2% upon 15 µM 5FU-loaded 25 µM PAMAM DL-3 micelle treatment. These results demonstrate that 5FU-loaded PAMAM conjugated di-n-dodecylamine treatment inhibits the proliferation of AGS cells in a generation-dependent manner.

In this study, the divergent and magnetic separation method is employed to prepare polyamidoamine (PAMAM) dendrons functionalized magnetic graphene oxide (MGG3) using graphene oxide supported MnFe2O4 nanoparticles as the support (MG), and ethylenediamine (EDA) and methylacrylate (MA) as the precursors of PAMAM dendron. Finally, palladium ions as active catalytic sites are immobilized on the support (MGG3‐Pd). The morphology and structure of the MGG3‐Pd nanocomposite thus produced are characterized by elemental analysis, Fourier transform infrared (FT‐IR), powder X‐ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), energy dispersive X‐ray spectroscopy (EDS), inductively coupled plasma atomic emission spectroscopy (ICP‐AES), X‐ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), and Zeta potential analysis. Subsequently, the catalytic activity of the MGG3‐Pd nanocomposite is studied in the reaction of 4‐nitrophenol (4‐NP) with sodium borohydride as the reducing agent at room temperature. The MGG3‐Pd catalyst is found to exhibit an excellent catalytic activity in the reduction of 4‐NP with a high yield over a short reaction time and at a rate constant (k) of 16.82 × 10−3 s−1. Furthermore, the MGG3‐Pd catalyst thus produced can be recycled at least after 10 runs of 4‐NP reduction without any considerable loss of Pd content. The reduction of other nitroaromatic compounds is also investigated under optimal conditions to illustrate the catalyst's versatility. [ABSTRACT FROM AUTHOR]

Jiebing Yang,* Jiayuan Zhang,* Jiakai Xing, Zhiyuan Shi, Haobo Han, Quanshun LiKey Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, People’s Republic of China*These authors contributed equally to this workBackground: The phenylboronic acid-functionalized polyamidoamine (PP) was employed as a gene carrier for Dz13 delivery, inducing an obvious anticancer response.Materials and methods: The Dz13 condensation ability of PP was evaluated through gel retardation assay. The cellular uptake mechanism of PP/Dz13 nanoparticles was studied using confocal laser scanning microscope and flow cytometer. The inhibition ability of cell proliferation, migration and invasion was investigated through MTT assay, flow cytometry, wound healing and Transwell migration assays, using hepatocarcinoma cell line HepG2 as a model. Finally, Western blotting analysis was used to detect the signaling pathway associated with the inhibition of cell apoptosis and migration induced by Dz13 delivery.Results: The carrier PP could efficiently condense Dz13 into stable nanoparticles at mass ratios of >1.5. The hydrodynamic diameter and zeta potential of PP/Dz13 nanoparticles were measured to be 204.77 nm and +22.00 mV at a mass ratio of 10.0, respectively. The nanoparticles could realize an efficient cellular uptake in sialic acid-dependent endocytosis manner. Moreover, the nanoparticles exhibited an obvious antiproliferation effect through the induction of cell apoptosis and cell cycle arrest due to the cleavage of c-Jun mRNA. Besides, the suppression of cell migration and invasion could be achieved after the PP/Dz13 transfection, attributing to the decreased expression level of MMP-2 and MMP-9.Conclusion: The PP provided a potential delivery system to achieve the tumor-targeting gene therapy.Keywords: phenylboronic acid, polyamidoamine, DNAzyme, gene therapy, antiproliferation effect, antimigration effect

Maintaining reasonable rheology is of vital importance in high temperature and high pressure drilling. In this study, a polyamidoamine low molecular weight polymer was synthesized with (Octadecadienoic acid) dipolymer, diethanolamine and triethylenetetramine and employed as rheology modifier in oil-based drilling fluid. The synthesized rheology modifier was characterized with Fourier Infrared (FTIR) spectra, gel permeation chromatography (GPC) and hydrogen nuclear magnetic resonance (1H-NMR) spectra. The effect of the rheology modifier on the rheological properties of organic clay suspension and typical oil-based drilling fluid was investigated. The underlying mechanism of the rheology modifier to improve the rheological properties under high temperatures was probed with X-ray diffraction (XRD) analysis and microscope observation. The results indicated that the rheology modifier is a low molecular weight polymer with multi-functional groups. The oil-based drilling fluid formulated with the novel rheology modifier exhibited optimal rheology and low high temperature and high pressure filtration loss after thermal aging at 180 °C. The rheology modifier accelerates the dispersion of organic clay particles and increases the interlayer spacing of organic clay even after high temperature treatment, which provides a high probability for the organic clay particles to form networks for desirable rheology. The synthesized rheology modifier shows promise in application in oil-based drilling fluid especially for high temperature and high pressure drilling. [ABSTRACT FROM AUTHOR]

Polyamidoamine dendrimer has been studied as an efficient gene carrier. Due to its anti-inflammatory properties, polyamidoamine is a useful gene carrier, especially for inflammatory diseases. However, the commonly used polyamidoamine generation 6 dendrimer (PG6) has higher cytotoxicity than low-molecular weight polyamidoamines, which limits its applications. Therefore, early-generation polyamidoamine dendrimers, such as generation 2 (PG2), have been investigated as an alternative to PG6, although PG2 has a lower transfection efficiency. In this study, to improve gene delivery efficiency, histidine and arginine were conjugated on the primary amines of PG2, synthesizing PG2HR. The gene delivery efficiency of PG2HR was higher than that of PG2 or of PG2 conjugated with only arginine (PG2R), which may be due to higher cellular uptake and endosomal escape of the plasmid DNA (pDNA)/PG2HR complex. In addition, PG2HR had lower cytotoxicity than polyethylenimine (25 kDa, PEI25k), PG2, and PG2R. Mechanism studies showed that PG2HR delivered pDNA into the cells mainly by clathrin-independent endocytosis and partly by macropinocytosis. The therapeutic potential of PG2HR-mediated gene delivery was evaluated in middle cerebral artery occlusion (MCAO)-reperfusion stroke animal models. Heme oxygenase-1 (HO-1) plasmid was delivered into the brain by local injection. The results showed that PG2HR had higher gene delivery efficiency in the brain than did PEI25k, PG2, or PG2R. Furthermore, compared to the pHO-1/PEI25k, pHO-1/PG2, and pHO-1/PG2R complexes, the pHO-1/PG2HR complex had reduced apoptosis levels and infarct sizes in ischemic brains. Therefore, because of its low cytotoxicity and high gene delivery efficiency, PG2HR may be useful for gene therapy of inflammatory diseases including ischemic stroke. Unlabelled Image [ABSTRACT FROM AUTHOR]

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Hemophagocytic lymphohistiocytosis (HLH) is a rare but severe disease characterized by immune hyperactivation and cytokine storm. Given the high mortality rate of HLH, there is a need for more effective diagnostic tools and treatments. The present study developed a dendrimer‑based protein biochip for rapid, sensitive and simultaneous detection of serum interferon (IFN)‑γ and endogenous anti‑IFN‑γ antibody (Ab) in patients with HLH. A gold biochip was modified with 1, 4‑phenylene diisothiocyanate (PDITC), polyamidoamine (PAMAM) or PDITC‑ activated PAMAM. The optimal immobilization concentration for Ab capture and the reaction concentration for detecting Ab on the PDITC‑activated PAMAM‑modified biochip were 6.25 and 3.12 μg/ml, respectively; the limit of detection of IFN‑γ protein was 50 pg/ml. The efficiency of the protein‑probed biochip in detecting IFN‑ γ and anti‑I FN‑γ Ab in serum samples from 77 patients with HLH was evaluated; the positive rates for IFN‑γ and anti‑IFN‑γ IgG Ab were 63.6% (49/77) and 61.0% (47/77), respectively. The present results demonstrated that the PDITC‑activated PAMAM‑modified biochip might be a sensitive tool for the specific detection of IFN‑γ and anti‑IFN‑γ Ab in serum, and might have clinical applicability for the diagnosis of HLH. [ABSTRACT FROM AUTHOR]

Platinum-based drugs are potent anticancer drugs and are effective for the treatment of various cancers. However, they are limited pharmacologically due to toxic side effects, drug resistance and poor water solubility. In order to overcome these limitations, platinum was incorporated onto polyamidoamine carriers together with alendronate and procaine hydrochloride to form a series of conjugates. Cytotoxicity was assessed using the sulforhodamine B assay on MCF-7, MDA-MB-231 and EA.hy926 cell lines. The polymer-drug conjugates showed cytotoxicity which was selective to the cancer cell lines. The free drugs decreased cell density in all cell lines and were nonspecific. These findings indicate that the incorporation of bioactive agents onto polymers can overcome cytotoxicity associated with the drugs. The selective inhibitory effects of the conjugates towards the cancer cell lines suggest that these conjugates are potential therapeutics for combination therapy. [ABSTRACT FROM AUTHOR]

Modification of the active layer is an effective method to improve the separation performance of the thin-film composite forward osmosis (FO) membranes. In this paper, the dendrimer polyam-idoamine (PAMAM) was in-situ integrated into the polyamide (PA) active layer via the interfacial polymerization. The separation performance results showed that the addition of PAMAM significantly improved the separation water flux of the modified FO membrane by 1.7 times, and the reverse salt flux was almost unchanged. In addition, the removal efficiency of the modified FO membrane for heavy metal ions was enhanced, with the rejection rates of various heavy metal ions all higher than 99.6%, and the corresponding water flux was also significantly enhanced. The PAMAM integrated with the active layer contained a large number of hydrophilic segments and terminal amine groups, which in situ enhanced the hydrophilicity and permeability of the active layer, and further improved the removal of heavy metal ions based on the coordination and electrostatic repulsion effects. The purpose of this paper is to provide a feasible way to improve the practical application performance of the FO membranes. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) modified by polyamidoamine (PAMAM)-immobilized 2,2,6,6-tetramethyl-1-piperidinyl-oxyl (TEMPO) as recoverable catalysts for catalytic oxidation of polyethylene glycol were designed and prepared, which were expected to combine the advantages of easy recovery of MNPs and high activity of PAMAM-immobilized TEMPO. The catalysts of MNPs modified by PAMAM-immobilized TEMPO (MNPs-PAMAM-T) were characterized by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analyzer (TGA), and transmission electron microscopy (TEM). The mean particle size of MNPs was about 10 nm. MNPs-PAMAM-T/NaBr/NaClO was used as catalytic system for catalytic oxidation of monomethoxy poly (ethylene glycol). The catalytic performances were affected by the loading amounts of TEMPO and PAMAM generations. It was shown that the catalyst with TEMPO loading of 5.198 mmol/g using G2.0 PAMAM-modified MNPs as carrier had the best catalytic performance, which could be up to 94% of the free TEMPO level. The efficient recovery of catalyst could be achieved by magnetic separation and the recycling performance was good. [ABSTRACT FROM AUTHOR]

A series of polyamidoamine (PAMAM) immobilized TEMPO macromolecular catalysts were prepared by condensation reduction reactions between carbonyl groups in 4-O-TEMPO and primary amines in PAMAM. The macromolecular catalyst and NaBr/NaClO were used as catalytic system for selective oxidation of cellulose in aqueous medium. Effects of various factors, such as TEMPO loading ratios and PAMAM generations, were studied on the catalytic performances. Compared with free TEMPO, the macromolecular catalyst with less than 50 % TEMPO loading ratio had a higher reaction rate in the initial stage of the reaction. Especially, the reaction rate of G1.0 PAMAM with 30 % TEMPO loading ratio was comparable to free TEMPO in the whole reaction process. Its cellulose oxidation degree (or catalytic activity) was also equivalent to the level of free TEMPO. Interestingly, the cellulose depolymerization degree of macromolecular catalyst was not affected by the cellulose oxidation degree and was lower than that of free TEMPO. The macromolecular catalyst could be recycled efficiently by the combination of supernatant circulation and salting-out extraction, and the recycling performance was excellent. [ABSTRACT FROM AUTHOR]

In this study, polyamidoamine (PAMAM) was added to raw lacquer in different proportions, and the curing process and properties of lacquer film were investigated by using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT‐IR), and scanning electron microscopy (SEM). To investigate the cross‐linking state between PAMAM and urushiol, NMR was used in this study. The experiments revealed that the comprehensive mechanical properties of modified‐film, especially the impact strength, were significantly improved. In addition, the touch‐free drying time of lacquer film decreased, and its alkali resistance was improved due to the cross‐linking of PAMAM and urushiol molecules. [ABSTRACT FROM AUTHOR]

Polyamidoamine drug conjugates containing ferrocene and platinum analogues were prepared in this study. Fourier transform infrared spectra confirmed the successful isolation of the conjugates with signals at 3300 cm−1 for amide N–H stretch and for C=O stretch at 1655–1635 cm−1 resulting from the conjugation of 4-ferrocenylketobutanoic acid. The polyamidoamine drug conjugate particle size was 247.1 nm and 258.3 nm suggesting their ability to exhibit in vitro phagocytosis. The average particle charges were 29 and 30.2, which was indicative of good stability and the capability to resist aggregation. In vitro cytotoxicity studies further revealed that the conjugates 1–5 did not exhibit cytotoxicity towards the normal cell lines (EA.hy926) whereas high cytotoxic activity was noted against the cancer cell lines (MCF-7 and MDA-MB-231) indicating selectivity towards cancer cell lines. Fc-PDA acted as a potentiating agent when incorporated together with DACH PtCl2 in the polymers, resulting in a good inhibitory effect in vitro. However, when combining Fc-PDA with K2PtCl4 in the polymer, an antagonistic effect was noted. The current findings implicate that the prepared conjugates hold the potential as therapeutics for the treatment of breast cancer. Further research is required to confirm this. [ABSTRACT FROM AUTHOR]

IL‐12 is a pleiotropic cytokine, which shows an ideal applicant for tumor immunotherapy, because of its features of creating an interconnection between innate (NK cells) and adaptive (cytotoxic T lymphocyte) immunity. IL‐12 gene therapy is a useful technique to deliver an immune‐modulatory gene directly into tumor site thereby limiting the adverse effects of systemic administration of IL‐12 proteins. One of the most largely investigated non‐viral gene carriers is polyamidoamine (PAMAM). In the current research, 5 and 3% of PAMAM primary amines were substituted to transmit the plasmid encoding IL‐12 gene to cells by cholesteryl chloroformate and alkyl‐PEG, respectively. The features of modified PAMAMs containing size and surface charge density, cytotoxicity, and transfection efficiency were investigated in colon cancer cells. in vitro experiment showed that this modified carrier with average size of about 160 nm and zeta potential of 30 mV was able to increase the level of IL‐12 production up to two folds as compared to that of the unmodified PAMAM. Improvement of the polymer hydrophobic balance along with of the modulation of the surface positive charge could provide an efficient and safe non‐viral IL‐12 gene for colon cancer immunogene therapy. [ABSTRACT FROM AUTHOR]

Synthetic nitric oxide (NO)-donating materials have been shown to have many beneficial effects when incorporated into biomedical materials. When released in the correct dosage, NO has been shown to increase the biocompatibility of blood and tissue contacting materials, but materials are often limited in the amount of NO that can be administered over a period of time. To address this, hyperbranched polyamidoamine (HPAMAM) was modified with the S-nitrosothiol, S-nitroso-N-acetyl-D-penicillamine, and nitrosated to form a controlled, high-capacity NO-donating compound (SNAP-HPAMAM). This compound has the potential of modifying polymers to release NO over long periods of time by being blended into a variety of base polymers. Nitric oxide release was triggered by photoinitiation and through passive ion-mediated release seen under physiological conditions. A material that delivers the beneficial dose of NO over a long period of time would be able to greatly increase the biocompatibility of long-term implantable devices. Structural analysis of a generation 2 HPAMAM molecule was done through Fourier transform infrared spectroscopy (FTIR), 1H nuclear magnetic resonance spectroscopy (NMR), and matrix assisted laser desorption ionization, time of flight (MALDI-TOF) mass spectrometry. The NO capacity of the finalized generation 2 SNAP-HPAMAM compound was approximately 1.90 ± 0.116 µmol NO/mg. Quantification of the functional groups in the compound proved that an average of 6.40 ± 0.309 reactive primary amine sites were present compared to the 8 reactive sites on a perfectly synthesized generation 2 dendrimer. There is a substantial advantage of using the hyper-branched HPAMAM over purified dendrimers in terms of reduced labor and expense while still providing a high-capacity NO donor that can be blended into different polymer matrices. [ABSTRACT FROM AUTHOR]

Iota-Carrageenan (i-carrageenan) was cross-linked with Polyamidoamine hyperbranched polymer generation 1 (PAMAM). The resulted hydrogels were dried using freeze-drying technique to give new bio-based i-carrageenan aerogels. These aerogels were characterized using FT-IR and their nitrogen contents were determined using Kjeldahl method. The morphology and the surface areas of the aerogels were investigated using scanning electron microscope and Brunauer–Emmett–Teller method, respectively. The ability of the aerogels to remediate different metal ions e.g. Cr(VI), Mn(II), Co(II), Cu(II), or Cd(II) and alphanol fast blue dye (acid dye) from aqueous medium was carefully investigated. The removal investigation was conducted without pH adjustment in case of metal ions and at pH 2 for acid dye. The aerogel with the higher nitrogen content (CAR4) exhibited the highest remediation efficiency of both metal ions and acid dye. [ABSTRACT FROM AUTHOR]

A linear polyamidoamine (PAA) named BAC-EDDS, containing metal chelating repeat units composed of two tert-amines and four carboxylic groups, has been prepared by the aza-Michael polyaddition of ethylendiaminodisuccinic (EDDS) with 2,2-bis(acrylamido)acetic acid (BAC). It was characterized by size exclusion chromatography (SEC), FTIR, UV–Vis and NMR spectroscopies. The pKa values of the ionizable groups of the repeat unit were estimated by potentiometric titration, using a purposely synthesized molecular ligand (Agly-EDDS) mimicking the structure of the BAC-EDDS repeat unit. Dynamic light scattering (DLS) and ζ-potential analyses revealed the propensity of BAC-EDDS to form stable nanoaggregates with a diameter of approximately 150 nm at pH 5 and a net negative charge at physiological pH, in line with an isoelectric point r1) and transverse (r2) relaxivities as a function of the externally applied static magnetic field were investigated and compared to the ones of commercial contrast agents. Furthermore, a model derived from the Solomon–Bloembergen–Morgan theory for the field dependence of the NMR relaxivity curves was applied and allowed us to evaluate the rotational correlation time of the complex (τ = 0.66 ns). This relatively high value is due to the dimensions of Gd-BAC-EDDS, and the associated rotational motion causes a peak in the longitudinal relaxivity at ca. 75 MHz, which is close to the frequencies used in clinics. The good performances of Gd-BAC-EDDS as a contrast agent were also confirmed through in vitro magnetic resonance imaging experiments with a 0.2 T magnetic field.

Recently, the number of gene and oligonucleotide drugs are increasing. Of various drug delivery systems (DDSs) for gene and oligonucleotide drugs, few examples of the clinical application of polymer as drug carriers are known, despite development of the novel polymers has been progressing. Cyclodextrin (CD) conjugates with starburst polyamidoamine (PAMAM) dendrimer (CDEs), as a new type of polymer-based carriers, were first published in 2001. After that, galactose-, lactose-, mannose-, fucose-, folate-, and polyethyleneglycol (PEG)-appended CDEs have been prepared for passive and active targeting for gene, oligonucleotide, and low-molecular-weight drugs. PEG-appended CDE formed polypsuedorotaxanes with α-CD and γ-CD, which are useful for a sustained release system of gene and oligonucleotide drugs. Interestingly, CDEs were found to have anti-inflammatory effects and anti-amyloid effects themselves, which have potential as active pharmaceutical ingredients. Most recently, CDE is reported to be a useful Cas9-RNA ribonucleoproteins (Cas9 RNP) carrier that induces genome editing in the neuron and brain. In this review, the history and progression of CDEs are overviewed.

One strategy for cancer treatment is combination therapy using nanoparticles (NPs), which has resulted in enhanced anti-cancer effects and reduced cytotoxicity of therapeutic agents. Polyamidoamine dendrimer (PAMAM) has attracted considerable attention because of its potential applications ranging from drug delivery to molecular encapsulation and gene therapy. In this study, PAMAM G5 modified with cholesteryl chloroformate and alkyl-PEG was applied for co-delivery of doxorubicin (DOX) and plasmid encoding TRAIL into colon cancer cells, in vitro and in vivo. The results showed DOX was efficiently encapsulated in modified carrier (M-PAMAM) with loading level about 90%, and the resulting DOX-loaded M-PAMAM complexed with TRAIL plasmid showed much stronger antitumor effect than M-PAMAM containing DOX or TRAIL plasmid. On the other hand, the obtained results demonstrated that the treatment of mice bearing C26 colon carcinoma with this developed co-delivery system significantly decreased tumor growth rate. Thus, this modified PAMAM G5 can be considered as a potential carrier for co-delivery of drug and gene in cancer therapy. [ABSTRACT FROM AUTHOR]

Background and Aims: 2,4,6‐Trichloroanisole (TCA) is a well‐recognised contaminant in the wine and whisky industries. In this work, several polymeric materials were tested through a hybrid strategy (computational and experimental studies) as potential fining agents for elimination of TCA. Methods and Results: Sodium alginate, polyaniline emeraldine base (PANI‐EB), polyaniline emeraldine salt (PANI‐ES) and three cross‐linked derivatives of different generations (G3, G4 and G5) of polyamidoamine (PAMAM) were tested. Materials were characterised by Fourier transform infrared spectroscopy and thermogravimetric analysis. The amount of material and the interaction time needed to achieve TCA sorption were optimised in a screening study. The binding capacity of the materials was then determined in methanol‐reconstituted wine and whisky solutions to demonstrate their effectiveness. The proportion of TCA in wine retained by PANI‐ES, PANI‐EB and PAMAM‐G5‐CD was greater than 75%, and for whisky all polymers except PANI‐ES retained greater than 75% of TCA. The concentration of phenolic substances of both methanol‐reconstituted solutions was measured after treatment; most of the polymers had no impact on the concentration of phenolic substances. The intermolecular interactions between the polymeric materials and TCA were characterised by computational studies involving molecular dynamics simulations. Conclusions: The polymers PAMAM G5‐CD and PANI‐EB retained the most TCA in reconstituted red wine and whisky solutions. Significance of the Study: The provision of efficient materials for the removal of TCA will improve the purification processes employed in beverage production. [ABSTRACT FROM AUTHOR]

Highlights • Polyamidoamine generation 1.0 triggers aggregation of gold nanoparticles. • Fatty acids disassemble the polyamidoamine/nanoparticle aggregates. • The aggregation/disassembling process is reflected by changes in UV–Vis spectra. • The spectroscopy is employed in determining total free fatty acids in edible oils. Abstract We synthesized polyamidoamine (PAMAM) dendrimers and citrate-capped gold nanoparticles (AuNPs), and explored the applicability of the PAMAM/AuNP assay in determining total free fatty acid (FFA) contents in edible oils based on a competitive colorimetry, in which the PAMAM-triggered AuNP aggregation was suppressed by FFAs. The generation and concentration of PAMAMs, the chain lengths of FFAs as well as the concentration and pH of the background electrolytes of the assay were optimized. The average acid values of the sunflower seed, corn and extra virgin olive oils determined by PAMAM/AuNP assay were 1.31 ± 0.07, 0.33 ± 0.02 and 1.49 ± 0.07, respectively, which were not significantly different from the corresponding 1.27 ± 0.08, 0.32 ± 0.01 and 1.61 ± 0.06 by the standard nonaqueous titration. Our results suggest that the method is promising in detecting FFAs in edible oils, and implementation of the method expands the technological scope for FFA analysis. [ABSTRACT FROM AUTHOR]