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Falanga A, Del Genio V, Kaufman EA, Zannella C, Franci G, Weck M, Galdiero S. Engineering of Janus-Like Dendrimers with Peptides Derived from Glycoproteins of Herpes Simplex Virus Type 1: Toward a Versatile and Novel Antiviral Platform. Int J Mol Sci 2021; 22:6488. [PMID: 34204295 PMCID: PMC8234430 DOI: 10.3390/ijms22126488] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 12/17/2022] Open
Abstract
Novel antiviral nanotherapeutics, which may inactivate the virus and block it from entering host cells, represent an important challenge to face viral global health emergencies around the world. Using a combination of bioorthogonal copper-catalyzed 1,3-dipolar alkyne/azide cycloaddition (CuAAC) and photoinitiated thiol-ene coupling, monofunctional and bifunctional peptidodendrimer conjugates were obtained. The conjugates are biocompatible and demonstrate no toxicity to cells at biologically relevant concentrations. Furthermore, the orthogonal addition of multiple copies of two different antiviral peptides on the surface of a single dendrimer allowed the resulting bioconjugates to inhibit Herpes simplex virus type 1 at both the early and the late stages of the infection process. The presented work builds on further improving this attractive design to obtain a new class of therapeutics.
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Affiliation(s)
- Annarita Falanga
- Department of Agricultural Sciences, University of Naples “Federico II”, Via Università 100, Portici, 80055 Naples, Italy;
| | - Valentina Del Genio
- Department of Pharmacy and CIRPEB, University of Naples “Federico II”, Via Montesano 49, 80131 Naples, Italy;
| | - Elizabeth A. Kaufman
- Department of Chemistry and Molecular Design Institute, New York University, New York, NY 10003, USA; (E.A.K.); (M.W.)
| | - Carla Zannella
- Department of Experimental Medicine, Second University of Naples, Via de Crecchio 7, 80138 Naples, Italy;
| | - Gianluigi Franci
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, 84081 Baronissi, Italy;
| | - Marcus Weck
- Department of Chemistry and Molecular Design Institute, New York University, New York, NY 10003, USA; (E.A.K.); (M.W.)
| | - Stefania Galdiero
- Department of Pharmacy and CIRPEB, University of Naples “Federico II”, Via Montesano 49, 80131 Naples, Italy;
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da Costa VCP, Annunziata O. Formation of Dendrimer Nanoassemblies by Oligomerization-Induced Liquid-Liquid Phase Separation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:5482-5490. [PMID: 28460527 DOI: 10.1021/acs.langmuir.7b00911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Dendrimers are hyperbranched macromolecules with applications in host-guest chemistry, self-assembly, nanocatalysis, and nanomedicine. We show that dendrimer-based globular nanoparticles are formed by using dendrimer oligomerization to isothermally induce liquid-liquid phase separation (LLPS). We first determined that LLPS of aqueous mixtures of the fourth-generation amino-functionalized poly(amido amine) dendrimer is observed by lowering temperature in the presence of sodium sulfate. In relation to LLPS, we experimentally characterized the effect of salt and dendrimer concentrations on the LLPS temperature and salt-dendrimer isothermal partitioning. Our results were theoretically examined using a two-parameter thermodynamic model. We then showed that the addition of a small amount of glutaraldehyde, which leads to the formation of soluble dendrimer oligomers by chemical cross-linking, increases the LLPS temperature. This implies that a dendrimer aqueous mixture, which is initially homogeneous at room temperature and exhibits LLPS only at relatively low temperatures, can exhibit LLPS at room temperature due to dendrimer oligomerization. The high dendrimer concentration inside the nanodroplets, produced from LLPS, accelerates dendrimer cross-linking, thereby yielding stable globular nanoparticles. These nanomaterials retain the host-guest properties of the initial dendrimers, indicating potential applications as nanocatalysts, extracting agents and drug carriers. Our work provides the basis for a new approach for obtaining dendrimer-based nanoassemblies by employing low-generation dendrimers as building blocks.
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Affiliation(s)
- Viviana C P da Costa
- Department of Chemistry & Biochemistry, Texas Christian University , Fort Worth, Texas 76129, United States
| | - Onofrio Annunziata
- Department of Chemistry & Biochemistry, Texas Christian University , Fort Worth, Texas 76129, United States
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3
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Wangpradit O, Adamcakova-Dodd A, Heitz K, Robertson L, Thorne PS, Luthe G. PAMAM dendrimers as nano carriers to investigate inflammatory responses induced by pulmonary exposure of PCB metabolites in Sprague-Dawley rats. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:2128-2137. [PMID: 26400242 PMCID: PMC4803647 DOI: 10.1007/s11356-015-5022-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 07/02/2015] [Indexed: 05/29/2023]
Abstract
Polychlorinated biphenyls (PCBs) persist and accumulate in the ecosystem depending upon the degree of chlorination of the biphenyl rings. Airborne PCBs are especially susceptible to oxidative metabolism, yielding mono- and di-hydroxy metabolites. We have previously demonstrated that 4-chlorobiphenyl hydroquinones (4-CB-HQs) acted as cosubstrates for arachidonic acid metabolism by prostaglandin H synthase (PGHS) and resulted in an increase of prostaglandin production in vitro. In the present study, we tested the capability of 4-CB-HQ to act as a co-substrate for PGHS catalysis in vivo. BQ and 4-CB-2',5'-HQ were administered intratracheally to male Sprague-Dawley rats (2.5 μmol/kg body weight) using nanosized polyamidoamine (PAMAM) dendrimers as carriers. We found that 24 h post application, PGE2 metabolites in kidney of rats treated with 4-CB-2',5'-HQ were significantly increased compared to the controls. The increase of PGE2 metabolites was correlated with increased alveolar macrophages in lung lavage fluid. The elevation of PGE2 synthesis is of great interest since it plays a crucial role in balancing homeostasis and inflammation where a chronic disturbance may increase risk of cancer. PAMAM dentrimers proved to be an effective transport medium and did not stimulate an inflammatory response themselves.
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Affiliation(s)
- Orarat Wangpradit
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, 100 Oakdale Campus, Iowa City, IA, 52242, USA
- Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
- Sirindhorn College of Public Health, Bansuan, Muang, Chonburi, 20000, Thailand
| | - Andrea Adamcakova-Dodd
- Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
- Pulmonary Toxicology Facility, Environmental Health Science Research Center, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
| | - Katharina Heitz
- Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
| | - Larry Robertson
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, 100 Oakdale Campus, Iowa City, IA, 52242, USA
- Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
| | - Peter S Thorne
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, 100 Oakdale Campus, Iowa City, IA, 52242, USA
- Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
- Pulmonary Toxicology Facility, Environmental Health Science Research Center, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA
| | - Gregor Luthe
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, 100 Oakdale Campus, Iowa City, IA, 52242, USA.
- Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, Iowa City, IA, 52242, USA.
- Saxion University of Applied Sciences, Institute for Life Science and Technology, Enschede, The Netherlands.
- Luthe-Pharma, Fabrikstrasse 3, 48599, Gronau, Germany.
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da Costa VCP, Annunziata O. Unusual liquid-liquid phase transition in aqueous mixtures of a well-known dendrimer. Phys Chem Chem Phys 2015; 17:28818-29. [PMID: 26451401 DOI: 10.1039/c5cp04642d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Liquid-liquid phase separation (LLPS) has been extensively investigated for polymer and protein solutions due to its importance in mixture thermodynamics, separation science and self-assembly processes. However, to date, no experimental studies have been reported on LLPS of dendrimer solutions. Here, it is shown that LLPS of aqueous solutions containing a hydroxyl-functionalized poly(amido amine) dendrimer of fourth generation is induced in the presence of sodium sulfate. Both the LLPS temperature and salt-dendrimer partitioning between the two coexisting phases at constant temperature were measured. Interestingly, our experiments show that LLPS switches from being induced by cooling to being induced by heating as the salt concentration increases. The two coexisting phases also show opposite temperature response. Thus, this phase transition exhibits a simultaneous lower and upper critical solution temperature-type behavior. Dynamic light-scattering and dye-binding experiments indicate that no appreciable conformational change occurs as the salt concentration increases. To explain the observed phase behavior, a thermodynamic model based on two parameters was developed. The first parameter, which describes dendrimer-dendrimer interaction energy, was determined by isothermal titration calorimetry. The second parameter describes the salt salting-out strength. By varying the salting-out parameter, it is shown that the model achieves agreement not only with the location of the experimental binodal at 25 °C but also with the slope of this curve around the critical point. The proposed model also predicts that the unusual temperature behavior of this phase transition can be described as the net result of two thermodynamic factors with opposite temperature responses: salt thermodynamic non-ideality and salting-out strength.
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Affiliation(s)
- Viviana C P da Costa
- Department of Chemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
| | - Onofrio Annunziata
- Department of Chemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
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Kalhapure RS, Kathiravan MK, Akamanchi KG, Govender T. Dendrimers - from organic synthesis to pharmaceutical applications: an update. Pharm Dev Technol 2013; 20:22-40. [PMID: 24299011 DOI: 10.3109/10837450.2013.862264] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dendrimers are a relatively new class of monodisperse polymers, which have tree-like spherical structures with well-defined sizes and shapes. Their unique structure has a significant impact on their physical and chemical properties. Research on dendrimers is of significant interest to scientists from all areas and their utility in various scientific fields, including pharmaceuticals, is expanding. The present review is comprehensive and covers different aspects of dendrimers viz. (1) synthesis, (2) properties and (3) pharmaceutical applications. The emphasis is on their applications as well as the current ongoing research status for drug targeting.
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Affiliation(s)
- Rahul S Kalhapure
- Discipline of Pharmaceutical Sciences, School of Health Sciences, University of KwaZulu-Natal , Durban , South Africa and
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van Dongen MA, Desai A, Orr BG, Baker JR, Holl MMB. Quantitative analysis of generation and branch defects in G5 poly(amidoamine) dendrimer. POLYMER 2013; 54:4126-4133. [PMID: 24058210 DOI: 10.1016/j.polymer.2013.05.062] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Although methods have been developed to synthesize and isolate generation 5 (G5) PAMAM dendrimers containing precise numbers of ligands per polymer particle, the presence of skeletal and generational defects in this material can substantially hamper the process. Here we provide a quantitative analysis of G5 PAMAM dendrimer defects via high performance liquid chromatography, potentiometric titration, mass spectrometry, size exclusion chromatography, and nuclear magnetic resonance. We identified, isolated, and characterized the major structural defects of G5 dendrimer, trailing generations, and dimer, trimer, and tetramer species. We determine that the G5 material present in the as-received mixture contains 93 arms on average. We have developed two model systems capable of generating the experimentally observed mass range and polydispersity at defect rates of 8-15%.
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Affiliation(s)
- Mallory A van Dongen
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA ; Michigan Nanotechnology Institute for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI 48109, USA
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8
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Cline EN, Li MH, Choi SK, Herbstman JF, Kaul N, Meyhöfer E, Skiniotis G, Baker JR, Larson RG, Walter NG. Paclitaxel-conjugated PAMAM dendrimers adversely affect microtubule structure through two independent modes of action. Biomacromolecules 2013; 14:654-64. [PMID: 23391096 PMCID: PMC3603340 DOI: 10.1021/bm301719b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Paclitaxel (Taxol) is an anticancer drug that induces mitotic arrest via microtubule hyperstabilization but causes side effects due to its hydrophobicity and cellular promiscuity. The targeted cytotoxicity of hydrophilic paclitaxel-conjugated polyamidoamine (PAMAM) dendrimers has been demonstrated in cultured cancer cells. Mechanisms of action responsible for this cytotoxicity are unknown, that is, whether the cytotoxicity is due to paclitaxel stabilization of microtubules, as is whether paclitaxel is released intracellularly from the dendrimer. To determine whether the conjugated paclitaxel can bind microtubules, we used a combination of ensemble and single microtubule imaging techniques in vitro. We demonstrate that these conjugates adversely affect microtubules by (1) promoting the polymerization and stabilization of microtubules in a paclitaxel-dependent manner, and (2) bundling preformed microtubules in a paclitaxel-independent manner, potentially due to protonation of tertiary amines in the dendrimer interior. Our results provide mechanistic insights into the cytotoxicity of paclitaxel-conjugated PAMAM dendrimers and uncover unexpected risks of using such conjugates therapeutically.
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Affiliation(s)
- Erika N. Cline
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI 48109
- Single Molecule Analysis Group, University of Michigan, Ann Arbor, MI 48109
| | - Ming-Hsin Li
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109
- Michigan Nanotechnology Institute for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI 48109
| | - Seok Ki Choi
- Michigan Nanotechnology Institute for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI 48109
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
| | | | - Neha Kaul
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Edgar Meyhöfer
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109
| | | | - James R. Baker
- Michigan Nanotechnology Institute for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI 48109
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
| | - Ronald G. Larson
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Nils G. Walter
- Single Molecule Analysis Group, University of Michigan, Ann Arbor, MI 48109
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109
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9
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Lu Y, Chen J, Lu Y, Gai P, Zhong H. Synthesis of poly(amido amine)-derived dendrimers with pendant benzoxazine groups and their thermal behavior. J Appl Polym Sci 2012. [DOI: 10.1002/app.37886] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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10
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Albertazzi L, Storti B, Marchetti L, Beltram F. Delivery and subcellular targeting of dendrimer-based fluorescent pH sensors in living cells. J Am Chem Soc 2010; 132:18158-67. [PMID: 21141854 DOI: 10.1021/ja105689u] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Synthesis and targeted delivery of dendrimer-based fluorescent biosensors in living HeLa cells are reported. Following electroporation dendrimers are shown to display specific subcellular localization depending on their size and surface charge and this property is preserved when they are functionalized with sensing moieties. We analyze the case of double dendrimer conjugation with pH-sensitive and pH-insensitive molecules leading to the realization of ratiometric pH sensors that are calibrated in vitro and in living cells. By tuning the physicochemical properties of the dendrimer scaffold sensors can be targeted to specific cellular compartments allowing selective pH measurements in different organelles in living cells. In order to demonstrate the modularity of this approach we present three different pH sensors with tuned H(+) affinity by appropriately choosing the pH-sensitive dye. We argue that the present methodology represents a general approach toward the realization of targetable ratiometric sensors suitable to monitor biologically relevant ions or molecules in living cells.
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Affiliation(s)
- Lorenzo Albertazzi
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, 56127 Pisa, Italy.
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11
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Lee S, Kwen HD, Lee SK, Nehete SV. Study on elution behavior of poly(amidoamine) dendrimers and their interaction with bovine serum albumin in asymmetrical flow field-flow fractionation. Anal Bioanal Chem 2009; 396:1581-8. [DOI: 10.1007/s00216-009-3353-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Revised: 11/25/2009] [Accepted: 11/25/2009] [Indexed: 10/20/2022]
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12
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Richer SM, Stewart NK, Webb SA, Tomaszewski JW, Oakley MG. High affinity binding to profilin by a covalently constrained, soluble mimic of phosphatidylinositol-4,5-bisphosphate micelles. ACS Chem Biol 2009; 4:733-9. [PMID: 19639958 DOI: 10.1021/cb900121r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Phosphoinositide (PI) lipids are essential regulators of a wide variety of cellular functions. We present here the preparation of a multivalent analogue of a phosphatidylinositol-4,5-bisphosphate (PIP(2)) micelle containing only the polar headgroup portion of this lipid. We show that this dendrimer binds to the cytoskeletal protein profilin with an affinity indistinguishable from that of PIP(2), despite the fact that profilin discriminates between PIP(2) and its monomeric hydrolysis product inositol-1,4,5-triphosphate (IP(3)) under physiological conditions. These data demonstrate that the diacylglycerol (DAG) moiety of PIP(2) is not required for high-affinity binding and suggest that profilin uses multivalency as a key means to distinguish between the intact lipid and IP(3). The class of soluble membrane analogues described here is likely to have broad applicability in the study of protein.PI interactions.
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Affiliation(s)
- Sarah M. Richer
- Department of Chemistry, Indiana University, 212 South Hawthorne Drive, Bloomington, Indiana 47405
| | - Nichole K. Stewart
- Department of Chemistry, Indiana University, 212 South Hawthorne Drive, Bloomington, Indiana 47405
| | - Sarah A. Webb
- Department of Chemistry, Indiana University, 212 South Hawthorne Drive, Bloomington, Indiana 47405
| | - John W. Tomaszewski
- Department of Chemistry, Indiana University, 212 South Hawthorne Drive, Bloomington, Indiana 47405
| | - Martha G. Oakley
- Department of Chemistry, Indiana University, 212 South Hawthorne Drive, Bloomington, Indiana 47405
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Kavitha M, Parida MR, Prasad E, Vijayan C, Deshmukh PC. Generation of Ag Nanoparticles by PAMAM Dendrimers and their Size Dependence on the Aggregation Behavior of Dendrimers. MACROMOL CHEM PHYS 2009. [DOI: 10.1002/macp.200900155] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Hamilton PD, Jacobs DZ, Rapp B, Ravi N. Surface Hydrophobic Modification of Fifth-Generation Hydroxyl-Terminated Poly(amidoamine) Dendrimers and Its Effect on Biocompatibility and Rheology. MATERIALS 2009. [PMCID: PMC5445743 DOI: 10.3390/ma2030883] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Water-soluble, commercially-available poly(amidoamine) (PAMAM) dendrimers are highly-branched, well-defined, monodisperse macromolecules having an ethylenediamine core and varying surface functional groups. Dendrimers are being employed in an increasing number of biomedical applications. In this study, commercially obtained generation 5 hydroxyl-terminated (G5OH) PAMAM dendrimers were studied as potential proteomimetics for ophthalmic uses. To this end, the surface of G5OH PAMAM dendrimers were hydrophobically modified with varying amounts of dodecyl moieties, (flexible long aliphatic chains), or cholesteryl moieties (rigid lipid found in abundance in biological systems). Dendrimers were characterized by 1H-NMR, DLS, DSC and HPLC. The hydrophobic modification caused aggregation and molecular interactions between dendrimers that is absent in unmodified dendrimers. In vitro tissue culture showed that increasing the amount of dodecyl modification gave a proportional increase in toxicity of the dendrimers, while with increasing cholesteryl modification there was no corresponding increase in toxicity. Storage and loss modulus were measured for selected formulations. The hydrophobic modification caused an increase in loss modulus, while the effect on storage modulus was more complex. Rheological properties of the dendrimer solutions were comparable to those of porcine lens crystallins.
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Affiliation(s)
- Paul D. Hamilton
- Research Branch, Department of Veterans Affairs Medical Center JC 151, 915 N. Grand Blvd. St. Louis, MO 63106, USA; E-Mail: (P.H.)
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Box 8096, 660 S. Euclid, St. Louis, MO 63110, USA; E-Mails: (D.J.); (B.R.)
| | - Donghui Z. Jacobs
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Box 8096, 660 S. Euclid, St. Louis, MO 63110, USA; E-Mails: (D.J.); (B.R.)
| | - Brian Rapp
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Box 8096, 660 S. Euclid, St. Louis, MO 63110, USA; E-Mails: (D.J.); (B.R.)
| | - Nathan Ravi
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Box 8096, 660 S. Euclid, St. Louis, MO 63110, USA; E-Mails: (D.J.); (B.R.)
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, MO 63130, USA
- Executive Branch, Department of Veterans Affairs Medical Center JC 151, 915 N. Grand Blvd. St. Louis, MO 63106, USA
- Author to whom correspondence should be addressed; E-Mail: ; Tel. +1-314 747-4464; Fax: +1-314 289-7009
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Biricova V, Laznickova A. Dendrimers: Analytical characterization and applications. Bioorg Chem 2009; 37:185-92. [PMID: 19703699 DOI: 10.1016/j.bioorg.2009.07.006] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 07/28/2009] [Accepted: 07/29/2009] [Indexed: 01/03/2023]
Abstract
This review focuses on analytical techniques used for separation and characterization of dendrimers and their derivatives. These macromolecules have been attractive material for a development of new drug carriers and imaging agents. They are also interesting for many biological and industrial applications. The review mentions a few of them.
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Affiliation(s)
- V Biricova
- Department of Biophysics and Physical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, 500 05 Hradec Kralove, Czech Republic.
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Das A, Zhou Y, Ivanov AA, Carter RL, Harden TK, Jacobson KA. Enhanced potency of nucleotide-dendrimer conjugates as agonists of the P2Y14 receptor: multivalent effect in G protein-coupled receptor recognition. Bioconjug Chem 2009; 20:1650-9. [PMID: 19572637 DOI: 10.1021/bc900206g] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The P2Y(14) receptor is a G protein-coupled receptor activated by uridine-5'-diphosphoglucose and other nucleotide sugars that modulates immune function. Covalent conjugation of P2Y(14) receptor agonists to PAMAM (polyamidoamine) dendrimers enhanced pharmacological activity. Uridine-5'-diphosphoglucuronic acid (UDPGA) and its ethylenediamine adduct were suitable functionalized congeners for coupling to several generations (G2.5-6) of dendrimers (both terminal carboxy and amino). Prosthetic groups, including biotin for avidin complexation, a chelating group for metal complexation (and eventual magnetic resonance imaging), and a fluorescent moiety, also were attached with the eventual goals of molecular detection and characterization of the P2Y(14) receptor. The activities of conjugates were assayed in HEK293 cells stably expressing the human P2Y(14) receptor. A G3 PAMAM conjugate containing 20 bound nucleotide moieties (UDPGA) was 100-fold more potent (EC(50) 2.4 nM) than the native agonist uridine-5'-diphosphoglucose. A molecular model of this conjugate docked in the human P2Y(14) receptor showed that the nucleotide-substituted branches could extend far beyond the dimensions of the receptor and be available for multivalent docking to receptor aggregates. Larger dendrimer carriers and greater loading favored higher potency. A similar conjugate of G6 with 147 out of 256 amino groups substituted with UDPGA displayed an EC(50) value of 0.8 nM. Thus, biological activity was either retained or dramatically enhanced in the multivalent dendrimer conjugates in comparison with monomeric P2Y(14) receptor agonists, depending on size, degree of substitution, terminal functionality, and attached prosthetic groups.
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Affiliation(s)
- Arijit Das
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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Heigl N, Bachmann S, Petter CH, Marchetti-Deschmann M, Allmaier G, Bonn GK, Huck CW. Near-Infrared Spectroscopic Study on Guest−Host Interactions Among G0−G7 Amine-Terminated Poly(amidoamine) Dendrimers and Porous Silica Materials for Simultaneously Determining the Molecular Weight and Particle Diameter by Multivariate Calibration Techniques. Anal Chem 2009; 81:5655-62. [DOI: 10.1021/ac900375z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N. Heigl
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
| | - S. Bachmann
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
| | - C. H. Petter
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
| | - M. Marchetti-Deschmann
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
| | - G. Allmaier
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
| | - G. K. Bonn
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
| | - C. W. Huck
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, 6020 Innsbruck, Austria and Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria
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18
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Tiong WHC, Damodaran G, Naik H, Kelly JL, Pandit A. Enhancing amine terminals in an amine-deprived collagen matrix. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:11752-11761. [PMID: 18774827 DOI: 10.1021/la801913c] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Collagen, though widely used as a core biomaterial in many clinical applications, is often limited by its rapid degradability which prevents full exploitation of its potential in vivo. Polyamidoamine (PAMAM) dendrimer, a highly branched macromolecule, possesses versatile multiterminal amine surface groups that enable them to be tethered to collagen molecules and enhance their potential. In this study, we hypothesized that incorporation of PAMAM dendrimer in a collagen matrix through cross-linking will result in a durable, cross-linked collagen biomaterial with free -NH 2 groups available for further multi-biomolecular tethering. The aim of this study was to assess the physicochemical properties of a G1 PAMAM cross-linked collagen matrix and its cellular sustainability in vitro. Different amounts of G1 PAMAM dendrimer (5 or 10 mg) were integrated into bovine-derived collagen matrices through a cross-linking process, mediated by 5 or 25 mM 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in 5 mM N-hydroxysuccinimide (NHS) and 50 mM 2-morpholinoethane sulfonic acid buffer at pH 5.5. The physicochemical properties of resultant matrices were investigated with scanning electron microscopy (SEM), collagenase degradation assay, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectra, and ninhydrin assay. Cellular sustainability of the matrices was assessed with Alamar Blue assay and SEM. There was no significant difference in cellular behavior between the treated and nontreated groups. However, the benefit of incorporating PAMAM in the cross-linking reaction was limited when higher concentrations of either agent were used. These results confirm the hypothesis that PAMAM dendrimer can be incorporated in the collagen cross-linking process in order to modulate the properties of the resulting cross-linked collagen biomaterial with free -NH 2 groups available for multi-biomolecular tethering.
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Affiliation(s)
- William H C Tiong
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Republic of Ireland
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19
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Chan JCY, Burugapalli K, Naik H, Kelly JL, Pandit A. Amine Functionalization of Cholecyst-Derived Extracellular Matrix with Generation 1 PAMAM Dendrimer. Biomacromolecules 2008; 9:528-36. [DOI: 10.1021/bm701055k] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Jeffrey C. Y. Chan
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Republic of Ireland, and Department of Plastic and Reconstructive Surgery, University Hospital Galway, Galway, Republic of Ireland
| | - Krishna Burugapalli
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Republic of Ireland, and Department of Plastic and Reconstructive Surgery, University Hospital Galway, Galway, Republic of Ireland
| | - Hemantkumar Naik
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Republic of Ireland, and Department of Plastic and Reconstructive Surgery, University Hospital Galway, Galway, Republic of Ireland
| | - John L. Kelly
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Republic of Ireland, and Department of Plastic and Reconstructive Surgery, University Hospital Galway, Galway, Republic of Ireland
| | - Abhay Pandit
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Republic of Ireland, and Department of Plastic and Reconstructive Surgery, University Hospital Galway, Galway, Republic of Ireland
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20
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Newkome GR, Shreiner CD. Poly(amidoamine), polypropylenimine, and related dendrimers and dendrons possessing different 1→2 branching motifs: An overview of the divergent procedures. POLYMER 2008. [DOI: 10.1016/j.polymer.2007.10.021] [Citation(s) in RCA: 313] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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21
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Schlapak R, Armitage D, Saucedo-Zeni N, Latini G, Gruber HJ, Mesquida P, Samotskaya Y, Hohage M, Cacialli F, Howorka S. Preparation and characterization of dense films of poly(amidoamine) dendrimers on indium tin oxide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:8916-24. [PMID: 17636991 DOI: 10.1021/la700476w] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Indium tin oxide (ITO) substrates were modified with a layer of poly(amidoamine) (PAMAM) dendrimers to change their surface properties and, in particular, the substrates' work function. The functionalization procedure involved the electrostatic adsorption of positively charged PAMAM dendrimers of generation five onto negatively polarized ITO surfaces. Three different PAMAM dendrimers were used: PAMAM-NH2 and PAMAM-OH with terminal amine and hydroxyl groups, respectively, as well as Q-PAMAM-NH2, which had been prepared from PAMAM-NH2 by quaternization of the dendrimer's terminal and internal amine groups with methyl iodide. The resulting organic films were analyzed by contact angle goniometry, X-ray photoelectron spectroscopy, ellipsometry, and Kelvin probe force microscopy to confirm the presence of a dense layer. A Langmuir isotherm was derived from surface densities of fluorescence-labeled PAMAM-NH2 dendrimers from which we deduced an equilibrium binding constant, K(eq), of (1.3 +/- 0.3) x 10(5) M(-1). Kelvin probe measurements of the contact potential difference revealed a high reduction of the work function from 4.9 eV for bare ITO to 4.3 eV for ITO with a dense film of PAMAM-NH2 of generation five. PAMAM-OH and Q-PAMAM-NH2 resulted in slightly smaller work function changes. This study illustrates that the work function of ITO can be tuned by adlayers composed of PAMAM dendrimers.
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Affiliation(s)
- Robert Schlapak
- Center for Biomedical Nanotechnology, Upper Austrian Research GmbH, A-4020 Linz, Austria
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22
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Martin H, Kinns H, Mitchell N, Astier Y, Madathil R, Howorka S. Nanoscale Protein Pores Modified with PAMAM Dendrimers. J Am Chem Soc 2007; 129:9640-9. [PMID: 17636906 DOI: 10.1021/ja0689029] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We describe nanoscale protein pores modified with a single hyperbranched dendrimer molecule inside the channel lumen. Sulfhydryl-reactive polyamido amine (PAMAM) dendrimers of generations 2, 3 and 5 were synthesized, chemically characterized, and reacted with engineered cysteine residues in the transmembrane pore alpha-hemolysin. Successful coupling was monitored using an electrophoretic mobility shift assay. The results indicate that G2 and G3 but not G5 dendrimers permeated through the 2.9 nm cis entrance to couple inside the pore. The defined molecular weight cutoff for the passage of hyperbranched PAMAM polymers is in contrast to the less restricted accessibility of flexible linear poly(ethylene glycol) polymers of comparable hydrodynamic volume. Their higher compactness makes sulfhydryl-reactive PAMAM dendrimers promising research reagents to probe the structure of porous membrane proteins with wide internal diameters. The conductance properties of PAMAM-modified proteins pores were characterized with single-channel current recordings. A G3 dendrimer molecule in the channel lumen reduced the ionic current by 45%, indicating that the hyperbranched and positively charged polymer blocked the passage of ions through the pore. In line with expectations, a smaller and less dense G2 dendrimer led to a less pronounced current reduction of 25%. Comparisons to recordings of PEG-modified pores revealed striking dissimilarities, suggesting that differences in the structural dynamics of flexible linear polymers vs compact dendrimers can be observed at the single-molecule level. Current recordings also revealed that dendrimers functioned as ion-selectivity filters and molecular sieves for the controlled passage of molecules. The alteration of pore properties with charged and hyperbranched dendrimers is a new approach and might be extended to inorganic nanopores with applications in sensing and separation technology.
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Affiliation(s)
- Hugh Martin
- Department of Chemistry, University College London, London WC1H 0AJ, England, United Kingdom
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23
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He ZG, Li GY, Shen SR, Li XL. Studies on polyamidoamine dendrimers as efficient gene delivery vector. J Biomater Appl 2007; 22:527-44. [PMID: 17623709 DOI: 10.1177/0885328207080005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Non-viral methods of gene delivery are attractive alternatives compared to virus-based gene delivery. Polyamidoamine (PAMAM) dendrimers are a new class of highly branched spherical polymers and have a unique surface of positively charged primary amine groups. They can form complex with DNA by electrostatic interaction, and deliver gene into cells. The ability of G5 PAMAM dendrimers binding and transferring DNA to cells has been investigated, and the effect of this complex to cell viability has been evaluated. G5 PAMAM dendrimers can bind DNA and transfer it to cultured cells efficiently, and have low cytotoxicity. The complex of PAMAM dendrimer-DNA can remain intact in a broad pH range, and also can prevent DNA from being degraded by restriction enzyme. Using the EGFP-C2 gene as marker genes, PAMAM dendrimers can deliver it to many organs after intravenous injection and have high expression in liver, kidney, lung, and spleen. Polyamidoamine- DNA complex can bind selectively plasma proteins, which may be correlated with its transportation in vivo. Polyamidoamine dendrimers' high-efficiency, low-cytotoxicity gene vector, appear to have potential for fundamental research and genetic therapy in vitro and in vivo.
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24
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Zhang D, Hamilton PD, Kao JLF, Venkataraman S, Wooley KL, Ravi N. Formation of nanogel aggregates by an amphiphilic cholesteryl-poly(amidoamine) dendrimer in aqueous media. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/pola.21958] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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Boas U, Christensen JB, Heegaard PMH. Dendrimers: design, synthesis and chemical properties. ACTA ACUST UNITED AC 2006. [DOI: 10.1039/b611813p] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Fischer-Durand N, Salmain M, Rudolf B, Vessières A, Zakrzewski J, Jaouen G. Synthesis of metal-carbonyl-dendrimer-antibody immunoconjugates: towards a new format for carbonyl metallo immunoassay. Chembiochem 2004; 5:519-25. [PMID: 15185376 DOI: 10.1002/cbic.200300800] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We report the preparation of metal-carbonyl-dendrimer-antibody conjugates. These metal-carbonyl-multilabeled antibodies are designed to be used in a new solid-phase-format carbonyl metallo immunoassay (CMIA). A fourth-generation polyamidoamine dendrimer was labeled with 10-25 (eta5-cyclopentadienyl)iron dicarbonyl (eta1-N-succinimidyl) entities. An antibody was chemically modified at its carbohydrate chains by a site-directed process used to preserve the antigen-antibody binding site. The antibody was then coupled with the dendrimer labeled with 10 metal carbonyl groups. An average of 1.4 labeled dendrimers were grafted per antibody molecule. These metal-carbonyl-dendrimer-antibody conjugates were used as new universal detection reagents that recognize their specific antigens. The antigens were spotted onto nitrocellulose membranes and detected by using the conjugates in combination with Fourier transform infrared spectroscopy. A detection level in the range 5-200 pmol per membrane was achieved. This approach opens the way to a new CMIA format.
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Affiliation(s)
- Nathalie Fischer-Durand
- Laboratoire de Chimie Organométallique, UMR CNRS 7576, Ecole Nationale Supérieure de Chimie de Paris, 11 rue Pierre et Marie Curie, 75231 Paris 05, France
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27
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Domański DM, Klajnert B, Bryszewska M. Incorporation of fluorescent probes into PAMAM dendrimers. Bioelectrochemistry 2004; 63:193-7. [PMID: 15110272 DOI: 10.1016/j.bioelechem.2003.09.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Accepted: 09/15/2003] [Indexed: 10/26/2022]
Abstract
Interactions of two fluorescent probes 1-(trimethylammoniumphenyl)-6-phenyl-1,3,5 hexatriene p-toluenesulfonate (TMA-DPH) and 12-(9-anthroyloxy) stearic acid (12-AS) with polyamidoamine (PAMAM) dendrimers were studied. Changes in fluorescence intensity and steady-state fluorescence anisotropy of TMA-DPH and 12-AS were monitored. It was found that 12-AS molecules incorporated into dendrimer cavities whereas TMA-DPH molecules aggregated on the surface of polymer. Dendrimer size had not significant impact on its host properties.
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Affiliation(s)
- D M Domański
- Department of General Biophysics, University of Łódź, 12/16 Banacha St., Łódź 90-237, Poland
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28
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Dugave C, Demange L. Cis-trans isomerization of organic molecules and biomolecules: implications and applications. Chem Rev 2003; 103:2475-532. [PMID: 12848578 DOI: 10.1021/cr0104375] [Citation(s) in RCA: 744] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Christophe Dugave
- CEA/Saclay, Département d'Ingénierie et d'Etudes des Protéines (DIEP), Bâtiment 152, 91191 Gif-sur-Yvette, France.
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29
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Abstract
Two dendritic peptides containing a branched lysine core and up to eight azobenzene moieties in the periphery were synthesized on solid support employing the omega-amino acid 4-(aminomethyl)phenylazobenzoic acid. With an additional peptidic tail consisting of an oligolysine portion, water solubility was achieved for the dendrimers, which allowed for the characterization of the cis/trans photoisomerization of the dendritic azobenzene species in both organic and aqueous media. Despite the interactions between the chromophores, which occur particularly in aqueous media, at higher dilution the photoisomerization process was found to proceed to extents that should permit photomodulation of molecular recognition processes between ligands grafted to the photosensitive azobenzene units and receptor molecules.
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Affiliation(s)
- A Cattani-Scholz
- Max-Planck-Institut für Biochemie, Am Klopferspitz 18a, 82152 Martinsried, Germany
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30
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Stephan H, Spies H, Johannsen B, Kauffmann C, Vögtle F. pH-controlled inclusion and release of oxyanions by dendrimers bearing methyl orange moieties. Org Lett 2000; 2:2343-6. [PMID: 10930279 DOI: 10.1021/ol006100r] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the synthesis of POPAM dendrimers, bearing up to 64 chromophores at their periphery. For these dendrimers, a radiotracer technique was used to study the liquid-liquid partition of pertechnetate and (14)C-labeled nucleotides in trichloromethane-aqueous systems. Inclusion and release of guest molecules can be controlled by changing the pH. The extraction efficacy increases with rising generation number.
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Affiliation(s)
- H Stephan
- Institut für Bioanorganische und Radiopharmazeutische Chemie, Forschungszentrum Rossendorf, 01314 Dresden, Germany
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