Advances in industrial ecology, desalination, and resource recovery have established that industrial wastewater, seawater, and brines are important and largely untapped sources of critical metals and elements. A Grand Challenge in metal recovery from industrial wastewater is to design and synthesize high capacity, recyclable and robust chelating ligands with tunable metal ion selectivity that c...

Polyamidoamine (PAMAM) dendrimers have previously been demonstrated to elicit systematically variable cyto- and eco-toxic responses, promising as the basis for structure-activity relationships governing nanotoxicological responses. In this study, increased production of intracellular reactive oxygen species (ROS), genotoxicity and apoptosis due to in vitro exposure of fish hepatocellular carcin...

Dendrimers are a relatively new class of polymer, with well-defined molecular structures. They are synthesized from a polyfunctional core by adding branched monomers that react with the functional groups of the core, in turn leaving end groups that can react again. This results in a large number of reactive terminal groups that increases after each cycle or " generation ". The structure of a gi...

Hollow titania nanoparticles of single-nanometer size have been prepared from titanium oxysulfate (TiOSO₄) using poly(amidoamine) (PAMAM) dendrimer molecules (Generations 5 with amino terminal groups) as a template. At low pH (pH 1), hydrolysis of the titania precursor was attenuated and the sol-gel reaction preferentially proceeded at the dendrimer surface. Calcination at 450°C yielded crystal...

Although many breast and lung cancers overexpress human epidermal growth factor receptor-2 (HER-2), no methods currently exist for effective and early detection of HER-2-positive cancers. To address this issue, we designed and synthesized dendrimer-based novel nano-imaging agents that contain gold nanoparticles (AuNPs) and gadolinium (Gd), conjugated with the humanized anti-HER-2 antibody (Herc...

Breast cancer is the leading cause of cancer-related deaths among women in the United States, and survival rates are lower for patients with metastases and/or triple-negative breast cancer (TNBC; ER, PR, and Her2 negative). Understanding the mechanisms of cancer metastasis is therefore crucial to identify new therapeutic targets and develop novel treatments to improve patient outcomes. A potent...

Epidermal growth factor receptor (EGFR)-targeted gene delivery is a promising approach in gene therapy against EGFR-positive cancer. In addition, macromolecules, such as polyamidoamine (PAMAM) dendrimers, are potential nonviral gene carriers in this therapy because of their biocompatibility and modifiable features. To achieve the goal of selectively enhancing the transfection efficiency in EGFR...

This article discusses the feasibility of using dendrimer enhanced ultrafiltration (DEUF)to recover Cu(II) from aqueous solutions. Building upon the results of fundamental investigations of Cu(II) binding to PAMAM dendrimers with ethylenediamine (EDA) core and terminal NH2 groups, we combine (i) dead-end ultrafiltration (UF) experiments with (ii) atomic force microscopy (AFM) characterization o...

Poly(amidoamine) (PAMAM) dendrimer nanoparticles have been demonstrated to elicit a well defined cytotoxicological response from mammalian cell lines, the response increasing systematically with dendrimer generation and number of surface amino groups. In this work, using generation G4, G5, and G6 dendrimers, this systematic response is furthermore demonstrated for the generation of reactive oxy...

Spatial control over the distribution and the aggregation of arginine-glycine-aspartate (RGD) peptides at the nanoscale significantly affects cell responses. For example, nanoscale clustering of RGD peptides can induce integrins to cluster, thus triggering complete cell signaling. Dendrimers have a unique, highly branched, nearly spherical and symmetrical structure with low polydispersity, nano...