1
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Vagenas D, Pispas S. Four-Component Statistical Copolymers by RAFT Polymerization. Polymers (Basel) 2024; 16:1321. [PMID: 38794514 PMCID: PMC11125712 DOI: 10.3390/polym16101321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/02/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
This manuscript serves as the starting point for in-depth research of multicomponent, statistical, methacrylate-based copolymers that potentially mimic the behavior of proteins in aqueous solutions. These synthetic macromolecules are composed of specially chosen comonomers: methacrylic acid (MAA), oligoethylene glycol methyl ether methacrylate (OEGMA475), 2-(dimethylamino)ethyl methacrylate (DMAEMA) and benzyl methacrylate (BzMA). Monomer choice was based on factors such as the chemical nature of pendant functional groups, the polyelectrolyte/polyampholyte and amphiphilic character and the overall hydrophobic-hydrophilic balance (HLB) of the obtained quaterpolymers. Their synthesis was achieved via a one-pot reversible addition fragmentation chain transfer (RAFT) polymerization in two distinct compositions and molecular architectures, linear and hyperbranched, respectively, in order to explore the effects of macromolecular topology. The resulting statistical quaterpolymers were characterized via 1H-NMR and ATR-FTIR spectroscopies. Their behavior in aqueous solutions was studied by dynamic (DLS) and electrophoretic light scattering (ELS) and fluorescence spectroscopy (FS), producing vital information concerning their self-assembly and the structure of the formed aggregates. The physicochemical studies were extended by tuning parameters such as the solution pH and ionic strength. Finally, the quaterpolymer behavior in FBS/PBS solutions was investigated to test their colloid stability and biocompatibility in an in vivo-mimicking, biological fluid environment.
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Affiliation(s)
| | - Stergios Pispas
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece;
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2
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Slezak AJ, Mansurov A, Raczy MM, Chang K, Alpar AT, Lauterbach AL, Wallace RP, Weathered RK, Medellin JE, Battistella C, Gray LT, Marchell TM, Gomes S, Swartz MA, Hubbell JA. Tumor Cell-Surface Binding of Immune Stimulating Polymeric Glyco-Adjuvant via Cysteine-Reactive Pyridyl Disulfide Promotes Antitumor Immunity. ACS CENTRAL SCIENCE 2022; 8:1435-1446. [PMID: 36313164 PMCID: PMC9615125 DOI: 10.1021/acscentsci.2c00704] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Indexed: 06/10/2023]
Abstract
Immune stimulating agents like Toll-like receptor 7 (TLR7) agonists induce potent antitumor immunity but are limited in their therapeutic window due to off-target immune activation. Here, we developed a polymeric delivery platform that binds excess unpaired cysteines on tumor cell surfaces and debris to adjuvant tumor neoantigens as an in situ vaccine. The metabolic and enzymatic dysregulation in the tumor microenvironment produces these exofacial free thiols, which can undergo efficient disulfide exchange with thiol-reactive pyridyl disulfide moieties upon intratumoral injection. These functional monomers are incorporated into a copolymer with pendant mannose groups and TLR7 agonists to target both antigen and adjuvant to antigen presenting cells. When tethered in the tumor, the polymeric glyco-adjuvant induces a robust antitumor response and prolongs survival of tumor-bearing mice, including in checkpoint-resistant B16F10 melanoma. The construct additionally reduces systemic toxicity associated with clinically relevant small molecule TLR7 agonists.
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Affiliation(s)
- Anna J. Slezak
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Aslan Mansurov
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Michal M. Raczy
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Kevin Chang
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Aaron T. Alpar
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Abigail L. Lauterbach
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Rachel P. Wallace
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Rachel K. Weathered
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Jorge E.G. Medellin
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Claudia Battistella
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Laura T. Gray
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Tiffany M. Marchell
- Committee
on Immunology, University of Chicago, Chicago, Illinois 60637, United States
| | - Suzana Gomes
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
| | - Melody A. Swartz
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
- Committee
on Immunology, University of Chicago, Chicago, Illinois 60637, United States
- Ben
May Department for Cancer Research, University
of Chicago, Chicago, Illinois 60637, United
States
- Committee
on Cancer Biology, University of Chicago, Chicago, Illinois 60637, United States
| | - Jeffrey A. Hubbell
- Pritzker
School of Molecular Engineering, University
of Chicago, Chicago, Illinois 60637, United States
- Committee
on Immunology, University of Chicago, Chicago, Illinois 60637, United States
- Committee
on Cancer Biology, University of Chicago, Chicago, Illinois 60637, United States
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3
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Geven M, d'Arcy R, Turhan ZY, El-Mohtadi F, Alshamsan A, Tirelli N. Sulfur-based oxidation-responsive polymers. Chemistry, (chemically selective) responsiveness and biomedical applications. Eur Polym J 2021. [DOI: 10.1016/j.eurpolymj.2021.110387] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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4
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Wang S. pH-Responsive Amphiphilic Carboxylate Polymers: Design and Potential for Endosomal Escape. Front Chem 2021; 9:645297. [PMID: 33834015 PMCID: PMC8021698 DOI: 10.3389/fchem.2021.645297] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/22/2021] [Indexed: 12/19/2022] Open
Abstract
The intracellular delivery of emerging biomacromolecular therapeutics, such as genes, peptides, and proteins, remains a great challenge. Unlike small hydrophobic drugs, these biotherapeutics are impermeable to the cell membrane, thus relying on the endocytic pathways for cell entry. After endocytosis, they are entrapped in the endosomes and finally degraded in lysosomes. To overcome these barriers, many carriers have been developed to facilitate the endosomal escape of these biomacromolecules. This mini-review focuses on the development of anionic pH-responsive amphiphilic carboxylate polymers for endosomal escape applications, including the design and synthesis of these polymers, the mechanistic insights of their endosomal escape capability, the challenges in the field, and future opportunities.
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Affiliation(s)
- Shiqi Wang
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
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5
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Altinbasak I, Arslan M, Sanyal R, Sanyal A. Pyridyl disulfide-based thiol–disulfide exchange reaction: shaping the design of redox-responsive polymeric materials. Polym Chem 2020. [DOI: 10.1039/d0py01215g] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review provides an overview of synthetic approaches utilized to incorporate the thiol-reactive pyridyl-disulfide motif into various polymeric materials, and briefly highlights its utilization to obtain functional materials.
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Affiliation(s)
| | - Mehmet Arslan
- Yalova University
- Faculty of Engineering
- Department of Polymer Materials Engineering
- 77100 Yalova
- Turkey
| | - Rana Sanyal
- Department of Chemistry
- Bogazici University
- Istanbul
- Turkey
- Center for Life Sciences and Technologies
| | - Amitav Sanyal
- Department of Chemistry
- Bogazici University
- Istanbul
- Turkey
- Center for Life Sciences and Technologies
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6
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Sui B, Cheng C, Xu P. Pyridyl Disulfide Functionalized Polymers as Nanotherapeutic Platforms. ADVANCED THERAPEUTICS 2019. [DOI: 10.1002/adtp.201900062] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Binglin Sui
- Department of Discovery and Biomedical Sciences College of Pharmacy University of South Carolina 715 Sumter Columbia SC 29208 USA
| | - Chen Cheng
- Department of Discovery and Biomedical Sciences College of Pharmacy University of South Carolina 715 Sumter Columbia SC 29208 USA
| | - Peisheng Xu
- Department of Discovery and Biomedical Sciences College of Pharmacy University of South Carolina 715 Sumter Columbia SC 29208 USA
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Zhu Y, Liu R, Huang H, Zhu Q. Vinblastine-Loaded Nanoparticles with Enhanced Tumor-Targeting Efficiency and Decreasing Toxicity: Developed by One-Step Molecular Imprinting Process. Mol Pharm 2019; 16:2675-2689. [PMID: 31050894 DOI: 10.1021/acs.molpharmaceut.9b00243] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Molecularly imprinted polymers have exhibited good performance as carriers on drug loading and sustained release. In this paper, vinblastine (VBL)-loaded polymeric nanoparticles (VBL-NPs) were prepared by a one-step molecular imprinting process, avoiding the waste and incomplete removal of the template, and evaluated as targeting carriers for VBL delivery after modification. Using acryloyl amino acid comonomers and disulfide cross-linkers, VBL-NPs were synthesized and then conjugated with poly(ethylene glycol)-folate. The dynamic size of the obtained VBL-NPs-PEG-FA was 258.3 nm (PDI = 0.250), and the encapsulation efficiency was 45.82 ± 1.45%. The nanoparticles of VBL-NPs-PEG-FA were able to completely release VBL during 48 h under a mimic tumor intracellular condition (pH 4.5, 10 mM glutathione (GSH)), displaying significant redox responsiveness, whereas the release rates were much slower in the mimic body liquid (pH 7.4, 2 μM GSH) and tumor extracellular environment (pH 6.5, 2 μM GSH). Furthermore, the carriers NPs-PEG-FA, prepared without VBL, showed satisfactory intrinsic hemocompatibility, cellular compatibility, and tumor-targeting properties: they could rapidly and efficiently accumulate to folate receptor positive Hela cells and then internalized via receptor-mediated endocytosis, and the retention in tumor tissues could last for over 48 h. Interestingly, VBL-NPs-PEG-FA could evidently increase the accumulation of VBL in tumor tissues while decreasing the distribution of VBL in organs, exert similar anticancer efficacy against Hela tumors in the xenograft model of nude mice to VBL injection, and significantly improve the abnormality of liver and spleen observed in VBL injection. VBL-NPs-PEG-FA has the potential to be the delivery carrier for VBL by enhancing the tumor-targeting efficacy of VBL and decreasing toxicity to normal tissues.
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Affiliation(s)
- Yongyan Zhu
- School of Traditional Chinese Medicine , Southern Medical University , Guangzhou 510515 , China
| | - Ruixuan Liu
- School of Traditional Chinese Medicine , Southern Medical University , Guangzhou 510515 , China
| | - Haoji Huang
- School of Traditional Chinese Medicine , Southern Medical University , Guangzhou 510515 , China
| | - Quanhong Zhu
- School of Traditional Chinese Medicine , Southern Medical University , Guangzhou 510515 , China
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Kangarlou S, Ramezanpour S, Balalaie S, Roudbar Mohammadi S, Haririan I. Curcumin-loaded nanoliposomes linked to homing peptides for integrin targeting and neuropilin-1-mediated internalization. PHARMACEUTICAL BIOLOGY 2017; 55:277-285. [PMID: 27937055 PMCID: PMC6130459 DOI: 10.1080/13880209.2016.1261301] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 08/17/2016] [Accepted: 11/07/2016] [Indexed: 06/06/2023]
Abstract
CONTEXT Curcumin, a naturally occurring polyphenol, has been extensively studied for its broad-spectrum anticancer effects. The potential benefits are, however, limited due to its poor water solubility and rapid degradation which result in low bioavailability on administration. OBJECTIVES This study encapsulates curcumin in nanoliposomes including an integrin-homing peptide combined with a C end R neuropilin-1 targeting motif for targeted delivery and receptor-mediated internalization, respectively. MATERIALS AND METHODS The linear GHHNGR (Glycine-Histidine-Histidine-Asparagine-Glycine-Arginine) was synthesized through F-moc chemistry on 2-chlorotrityl chloride resin and conjugated to oleic acid. The lipoyl-peptide units were then co-assembled with lecithin and 0-75 mole % Tween-80 into liposomes. Curcumin was passively entrapped using a film hydration technique and its degradation profile was examined within seven consecutive days. The cytotoxic effects of the curcumin-loaded liposomes were studied on MCF-7 and MDA-MB-468, during 24 h exposure in MTT assay. RESULTS The maximum curcumin entrapment (15.5% W/W) and minimum degradation (< 23%) were obtained in a pH switch loading method from 5.7 to 8, in nanoliposomes (< 50 nm) containing oleyl-peptide, lecithin and Tween-80 (1:1:0.75 mole ratio). The oleyl-peptide did not prove any haemolytic activity (< 1.5%) up to 10-fold of its experimental concentration. The curcumin-loaded liposomes displayed significant reduction in the viabilities of MCF-7 (IC50 3.8 μM) and MDA-MB-468 (IC50 5.4 μM). DISCUSSION AND CONCLUSION This study indicated potential advantages of the peptide-conjugated liposomes in drug transport to the cancer cells. This feature might be an outcome of probable interactions between the targeted nanoliposomes with the integrin and neuropilin-1 receptors.
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Affiliation(s)
- Sogol Kangarlou
- Department of Pharmaceutical Biomaterials School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Sorour Ramezanpour
- Peptide Chemistry Research Center, K.N. Toosi University of Technology, Tehran, Iran
| | - Saeed Balalaie
- Peptide Chemistry Research Center, K.N. Toosi University of Technology, Tehran, Iran
| | - Shahla Roudbar Mohammadi
- Department of Medical Mycology School of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ismaeil Haririan
- Department of Pharmaceutical Biomaterials School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
- Medical Biomaterials Research Center, Tehran University of Medical Sciences, Tehran, Iran
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9
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Bakewell SJ, Carie A, Costich TL, Sethuraman J, Semple JE, Sullivan B, Martinez GV, Dominguez-Viqueira W, Sill KN. Imaging the delivery of drug-loaded, iron-stabilized micelles. NANOMEDICINE : NANOTECHNOLOGY, BIOLOGY, AND MEDICINE 2017; 13:1353-1362. [PMID: 28115246 PMCID: PMC5451294 DOI: 10.1016/j.nano.2017.01.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/19/2016] [Accepted: 01/11/2017] [Indexed: 12/18/2022]
Abstract
Nanoparticle drug carriers hold potential to improve current cancer therapy by delivering payload to the tumor environment and decreasing toxic side effects. Challenges in nanotechnology drug delivery include plasma instability, site-specific delivery, and relevant biomarkers. We have developed a triblock polymer comprising a hydroxamic acid functionalized center block that chelates iron to form a stabilized micelle that physically entraps chemotherapeutic drugs in the hydrophobic core. The iron-imparted stability significantly improves the integrity of the micelle and extends circulation pharmacokinetics in plasma over that of free drug. Furthermore, the paramagnetic properties of the iron-crosslinking exhibits contrast in the tumors for imaging by magnetic resonance. Three separate nanoparticle formulations demonstrate improved anti-tumor efficacy in xenograft models and decreased toxicity. We report a stabilized polymer micelle that improves the tolerability and efficacy of chemotherapeutic drugs, and holds potential for non-invasive MRI to image drug delivery and deposition in the tumor.
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Affiliation(s)
| | | | | | | | | | | | - Gary V Martinez
- Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA
| | - William Dominguez-Viqueira
- Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA
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11
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Tong M, An X, Pan W, Liu H, Zhao Y. Synthesis and properties of stimuli-sensitive heterografted toothbrush-like terpolymers with a linear handle and two types of V-shaped grafts. Polym Chem 2016. [DOI: 10.1039/c6py00182c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Straightforward syntheses were performed to generate amphiphilic heterograftedPNIPAM(PAA)2m(PCL)2mcopolymers, which could self-assemble into versatile nanoobjects for thermo, pH and additive triggered controlled release of doxorubicin.
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Affiliation(s)
- Min Tong
- Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials
- College of Chemistry
- Chemical Engineering and Materials Science
| | - Xiaonan An
- Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials
- College of Chemistry
- Chemical Engineering and Materials Science
| | - Weidong Pan
- Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials
- College of Chemistry
- Chemical Engineering and Materials Science
| | - Huanhuan Liu
- Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials
- College of Chemistry
- Chemical Engineering and Materials Science
| | - Youliang Zhao
- Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials
- College of Chemistry
- Chemical Engineering and Materials Science
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12
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Zhou Z, Murdoch WJ, Shen Y. A linear polyethylenimine (LPEI) drug conjugate with reversible charge to overcome multidrug resistance in cancer cells. POLYMER 2015. [DOI: 10.1016/j.polymer.2015.08.061] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Parodi A, Corbo C, Cevenini A, Molinaro R, Palomba R, Pandolfi L, Agostini M, Salvatore F, Tasciotti E. Enabling cytoplasmic delivery and organelle targeting by surface modification of nanocarriers. Nanomedicine (Lond) 2015; 10:1923-40. [PMID: 26139126 PMCID: PMC5561781 DOI: 10.2217/nnm.15.39] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Nanocarriers are designed to specifically accumulate in diseased tissues. In this context, targeting of intracellular compartments was shown to enhance the efficacy of many drugs and to offer new and more effective therapeutic approaches. This is especially true for therapies based on biologicals that must be encapsulated to favor cell internalization, and to avoid intracellular endosomal sequestration and degradation of the payload. In this review, we discuss specific surface modifications designed to achieve cell cytoplasm delivery and to improve targeting of major organelles; we also discuss the therapeutic applications of these approaches. Last, we describe some integrated strategies designed to sequentially overcome the biological barriers that separate the site of administration from the cell cytoplasm, which is the drug's site of action.
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Affiliation(s)
- Alessandro Parodi
- Department of Nanomedicine, Houston Methodist Research Institute, 6670 Bertner Ave., Houston, TX 77030, USA
- Fondazione IRCCS SDN, Via Gianturco 113, 80143 Naples, Italy
| | - Claudia Corbo
- Fondazione IRCCS SDN, Via Gianturco 113, 80143 Naples, Italy
| | - Armando Cevenini
- Department of Molecular Medicine & Medical Biotechnology, University of Naples “Federico II”, Via Sergio Pansini 5, Naples 80131, Italy
- CEINGE, Biotecnologie Avanzate s.c.a.r.l., Via G. Salvatore 486, 80145 Naples, Italy
| | - Roberto Molinaro
- Department of Nanomedicine, Houston Methodist Research Institute, 6670 Bertner Ave., Houston, TX 77030, USA
- Clinica Chirurgica I, Dipartimento di Scienze Chirurgiche Oncologiche e Gastroeterologiche, Università di Padova, Via Giustiniani 2, 35128 Padova, Italy
| | - Roberto Palomba
- Fondazione IRCCS SDN, Via Gianturco 113, 80143 Naples, Italy
| | - Laura Pandolfi
- Department of Nanomedicine, Houston Methodist Research Institute, 6670 Bertner Ave., Houston, TX 77030, USA
- College of Materials Science & Optoelectronic Technology, University of Chinese Academy of Science, 19A Yuquanlu, Beijing, China
| | - Marco Agostini
- Clinica Chirurgica I, Dipartimento di Scienze Chirurgiche Oncologiche e Gastroeterologiche, Università di Padova, Via Giustiniani 2, 35128 Padova, Italy
| | - Francesco Salvatore
- Fondazione IRCCS SDN, Via Gianturco 113, 80143 Naples, Italy
- CEINGE, Biotecnologie Avanzate s.c.a.r.l., Via G. Salvatore 486, 80145 Naples, Italy
| | - Ennio Tasciotti
- Department of Nanomedicine, Houston Methodist Research Institute, 6670 Bertner Ave., Houston, TX 77030, USA
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Qian J, Xu M, Suo A, Xu W, Liu T, Liu X, Yao Y, Wang H. Folate-decorated hydrophilic three-arm star-block terpolymer as a novel nanovehicle for targeted co-delivery of doxorubicin and Bcl-2 siRNA in breast cancer therapy. Acta Biomater 2015; 15:102-16. [PMID: 25545322 DOI: 10.1016/j.actbio.2014.12.018] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/12/2014] [Accepted: 12/18/2014] [Indexed: 01/18/2023]
Abstract
To minimize the side effects and enhance the efficiency of chemotherapy, a novel folate-decorated hydrophilic cationic star-block terpolymer, [poly(l-glutamic acid γ-hydrazide)-b-poly(N,N-dimethylaminopropyl methacrylamide)]3-g-poly(ethylene glycol) ((PGAH-b-PDMAPMA)3-g-PEG), with disulfide linkages between the PEG and PDMAPMA blocks, was developed for targeted co-delivery of doxorubicin and Bcl-2 small interfering RNA (siRNA) into breast cancer cells. The terpolymer was synthesized by a combination of ring-opening polymerization, reversible addition-fragmentation chain transfer polymerization, PEGylation and hydrazinolysis. The chemical structures of the polymers were confirmed by (1)H-NMR analysis. The terpolymer could conjugate doxorubicin via an acid-labile hydrazone linkage and simultaneously efficiently complex siRNA through electrostatic interaction at N/P ratios of ⩾4:1 to form "two-in-one" nanomicelleplexes, which displayed a spherical shape and had an average size of 101.3 nm. The doxorubicin loading efficiency and content were 61.0 and 13.23%, respectively. The cytotoxicity, drug release profile, targeting ability, cellular uptake and intracellular distribution of the nanomicelleplexes were evaluated in vitro. We found that the release behaviors of doxorubicin and siRNA had a pH/reduction dual dependency. They were released faster under reductive acidic conditions (pH 5.0, glutathione: 10mM) than under physiological conditions (pH 7.4). The folate-decorated nanomicelleplexes could deliver doxorubicin and Bcl-2 siRNA more efficiently into the same MCF-7 cell and exhibited a higher cytotoxicity than non-targeted nanomicelleplexes. These results indicate that the terpolymer could act as an efficient vehicle for targeted intracellular co-delivery of doxorubicin and therapeutic siRNA in cancer therapy.
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15
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Intracellular delivery system for antibody-Peptide drug conjugates. Mol Ther 2015; 23:907-917. [PMID: 25669432 DOI: 10.1038/mt.2015.22] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 01/21/2015] [Indexed: 12/11/2022] Open
Abstract
Antibodies armed with biologic drugs could greatly expand the therapeutic potential of antibody-drug conjugates for cancer therapy, broadening their application to disease targets currently limited by intracellular delivery barriers. Additional selectivity and new therapeutic approaches could be realized with intracellular protein drugs that more specifically target dysregulated pathways in hematologic cancers and other malignancies. A multifunctional polymeric delivery system for enhanced cytosolic delivery of protein drugs has been developed that incorporates endosomal-releasing activity, antibody targeting, and a biocompatible long-chain ethylene glycol component for optimized safety, pharmacokinetics, and tumor biodistribution. The pH-responsive polymeric micelle carrier, with an internalizing anti-CD22 monoclonal targeting antibody, effectively delivered a proapoptotic Bcl-2 interacting mediator (BIM) peptide drug that suppressed tumor growth for the duration of treatment and prolonged survival in a xenograft mouse model of human B-cell lymphoma. Antitumor drug activity was correlated with a mechanistic induction of the Bcl-2 pathway biomarker cleaved caspase-3 and a marked decrease in the Ki-67 proliferation biomarker. Broadening the intracellular target space by more effective delivery of protein/peptide drugs could expand the repertoire of antibody-drug conjugates to currently undruggable disease-specific targets and permit tailored drug strategies to stratified subpopulations and personalized medicines.
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16
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Laskar P, Saha B, Ghosh SK, Dey J. PEG based random copolymer micelles as drug carriers: the effect of hydrophobe content on drug solubilization and cytotoxicity. RSC Adv 2015. [DOI: 10.1039/c4ra11479e] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The effect of hydrophobe content on PEG based random polymeric micelles as drug carriers: a comparative study.
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Affiliation(s)
- Partha Laskar
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur-721 302
- India
| | - Biswajit Saha
- Department of Biotechnology
- Indian Institute of Technology
- Kharagpur-721 302
- India
| | - Sudip Kumar Ghosh
- Department of Biotechnology
- Indian Institute of Technology
- Kharagpur-721 302
- India
| | - Joykrishna Dey
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur-721 302
- India
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17
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Silencing bcl-2 expression in epithelial cancer cells using "smart" particles. J Funct Biomater 2014; 5:167-82. [PMID: 25229941 PMCID: PMC4192611 DOI: 10.3390/jfb5030167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 07/26/2014] [Accepted: 07/28/2014] [Indexed: 11/17/2022] Open
Abstract
Short interfering RNA (siRNA) targeted against anti-apoptotic Bcl-2 protein proved to knockdown its expression and trigger cancer cell death. We used degradable, pH-sensitive, comb-like [P(EAA-co-BMA)-b-PNASI-g-P(HMA-co-TMAEMA)] polymer to condense anti-Bcl-2 siRNA into "smart" particles, which proved to shuttle their cargo past the endosomal membrane and into the cytoplasm of HeLa and UM-SCC-17B cancer cells. HeLa and UM-SCC-17B cancer cells were treated with anti-Bcl-2 particles followed by quantifying Bcl-2 mRNA and protein levels using qRT-PCR and western blotting, respectively. "Smart" anti-Bcl-2 particles selectively suppress Bcl-2 mRNA and protein levels in HeLa cells by 50%-60% and 79%-81%, respectively. Similarly, "smart" anti-Bcl-2 particles inhibited Bcl-2 mRNA levels by 30%, 40%, and 20% upon incubation with UM-SCC-17B cancer cells for 48, 72, and 96 h, respectively. Bcl-2 protein expression in UM-SCC-17B cancer cells was inhibited by 30% after treatment for 72 h. Results show that pH-sensitive comb-like polymer complex anti-Bcl-2 siRNA forming "smart" nanoparticles that deliver their cargo into the cytoplasm of HeLa and UM-SCC-17B cancer cells causing Bcl-2 knockdown at the mRNA and protein levels.
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18
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Laskar P, Samanta S, Ghosh SK, Dey J. In vitro evaluation of pH-sensitive cholesterol-containing stable polymeric micelles for delivery of camptothecin. J Colloid Interface Sci 2014; 430:305-14. [DOI: 10.1016/j.jcis.2014.05.068] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 05/30/2014] [Accepted: 05/31/2014] [Indexed: 12/28/2022]
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19
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Du M, Guo Q, Feng H, Lu G, Huang X. Derivation of Oridonin with Bioreduction-Responsive Disulfide Bond. CHINESE J CHEM 2014. [DOI: 10.1002/cjoc.201300761] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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20
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Mercury sensing and toxicity studies of novel latex fabricated silver nanoparticles. Bioprocess Biosyst Eng 2014; 37:2223-33. [DOI: 10.1007/s00449-014-1200-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 04/15/2014] [Indexed: 01/02/2023]
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21
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He X, Ding M, Li J, Tan H, Fu Q, Li L. Biodegradable multiblock polyurethane micelles with tunable reduction-sensitivity for on-demand intracellular drug delivery. RSC Adv 2014. [DOI: 10.1039/c4ra01478b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Biodegradable polyurethanes bearing varied amounts of disulfide linkages in the backbone can rapidly enter tumor cells and efficiently transport the encapsulated payloads into cytosol, resulting in controlled inhibition effects against cancer cells. The nanocarriers are promising candidates for on-demand intracellular drug delivery applications.
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Affiliation(s)
- Xueling He
- Institute of Biomedical Engineering
- West China School of Preclinical and Forensic Medicine
- Sichuan University
- Chengdu, China
| | - Mingming Ding
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065, China
| | - Jiehua Li
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065, China
| | - Hong Tan
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065, China
| | - Qiang Fu
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065, China
| | - Liang Li
- Institute of Biomedical Engineering
- West China School of Preclinical and Forensic Medicine
- Sichuan University
- Chengdu, China
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22
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Harada A, Matsuki R, Ichimura SI, Yuba E, Kono K. Intracellular environment-responsive stabilization of polymer vesicles formed from head-tail type polycations composed of a polyamidoamine dendron and poly(L-lysine). Molecules 2013; 18:12168-79. [PMID: 24084020 PMCID: PMC6269863 DOI: 10.3390/molecules181012168] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 09/18/2013] [Accepted: 09/23/2013] [Indexed: 01/23/2023] Open
Abstract
For the development of effective drug carriers, nanocapsules that respond to micro-environmental changes including a decrease in pH and a reductive environment were prepared by the stabilization of polymer vesicles formed from head-tail type polycations, composed of a polyamidoamine dendron head and a poly(l-lysine) tail (PAMAM dendron-PLL), through the introduction of disulfide bonds between the PLL tails. Disulfide bonds were successfully introduced through the reaction of Lys residues in the PAMAM dendron-PLL polymer vesicles with 2-iminothiolane. The stabilization of PAMAM dendron-PLL polymer vesicles was confirmed by dynamic light scattering measurements. In acid-base titration experiments, nanocapsules cross-linked by disulfide bonds had a buffering effect during the cellular uptake process. The PAMAM dendron-PLL nanocapsules were used to incorporate the fluorescent dyes rhodamine 6G and fluorescein as a drug model. Cationic rhodamine 6G was generally not released from the nanocapsules because of the electrostatic barrier of the PLL membrane. However, the nanocapsules were destabilized at high glutathione concentrations corresponding to intracellular concentrations. Rhodamine 6G was immediately released from the nanocapsules because of destabilization upon the cleavage of disulfide bonds. This release of rhodamine 6G from the nanocapsules was also observed in HeLa cells by laser confocal microscopy.
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Affiliation(s)
- Atsushi Harada
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
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23
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Nidhin M, Nazeer SS, Jayasree RS, Kiran MS, Nair BU, Sreeram KJ. Flower shaped assembly of cobalt ferrite nanoparticles: application as T2 contrast agent in MRI. RSC Adv 2013. [DOI: 10.1039/c3ra23232h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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24
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Yue Y, Wu C. Progress and perspectives in developing polymeric vectors for in vitro gene delivery. Biomater Sci 2013; 1:152-170. [DOI: 10.1039/c2bm00030j] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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25
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Berguig GY, Convertine AJ, Shi J, Palanca-Wessels MC, Duvall CL, Pun SH, Press OW, Stayton PS. Intracellular delivery and trafficking dynamics of a lymphoma-targeting antibody-polymer conjugate. Mol Pharm 2012; 9:3506-14. [PMID: 23075320 DOI: 10.1021/mp300338s] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ratiometric fluorescence and cellular fractionation studies were employed to characterize the intracellular trafficking dynamics of antibody-poly(propylacrylic acid) (PPAA) conjugates in CD22+ RAMOS-AW cells. The HD39 monoclonal antibody (mAb) directs CD22-dependent, receptor-mediated uptake in human B-cell lymphoma cells, where it is rapidly trafficked to the lysosomal compartment. To characterize the intracellular-release dynamics of the polymer-mAb conjugates, HD39-streptavidin (HD39/SA) was dual-labeled with pH-insensitive Alexa Fluor 488 and pH-sensitive pHrodo fluorophores. The subcellular pH distribution of the HD39/SA-polymer conjugates was quantified as a function of time by live-cell fluorescence microscopy, and the average intracellular pH value experienced by the conjugates was also characterized as a function of time by flow cytometry. PPAA was shown to alter the intracellular trafficking kinetics strongly relative to HD39/SA alone or HD39/SA conjugates with a control polymer, poly(methacryclic acid) (PMAA). Subcellular trafficking studies revealed that after 6 h, only 11% of the HD39/SA-PPAA conjugates had been trafficked to acidic lysosomal compartments with values at or below pH 5.6. In contrast, the average intracellular pH of HD39/SA alone dropped from 6.7 ± 0.2 at 1 h to 5.6 ± 0.5 after 3 h and 4.7 ± 0.6 after 6 h. Conjugation of the control polymer PMAA to HD39/SA showed an average pH drop similar to that of HD39/SA. Subcellular fractionation studies with tritium-labeled HD39/SA demonstrated that after 6 h, 89% of HD39/SA was associated with endosomes (Rab5+) and lysosomes (Lamp2+), while 45% of HD39/SA-PPAA was translocated to the cytosol (lactate dehydrogenase+). These results demonstrate the endosomal-releasing properties of PPAA with antibody-polymer conjugates and detail their intracellular trafficking dynamics and subcellular compartmental distributions over time.
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Affiliation(s)
- Geoffrey Y Berguig
- Department of Bioengineering, University of Washington , Seattle, Washington 98195-5061, United States
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26
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Sevimli S, Inci F, Zareie HM, Bulmus V. Well-Defined Cholesterol Polymers with pH-Controlled Membrane Switching Activity. Biomacromolecules 2012; 13:3064-75. [DOI: 10.1021/bm300846e] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
| | - Fatih Inci
- Department of Molecular
Biology-Genetics and Biotechnology Program (MOBGAM), Istanbul Technical University, Istanbul 34469, Turkey
| | - Hadi M. Zareie
- Department of Electrical-Electronics
Engineering and Nanotechnology Graduate Program, Gediz University, Izmir 35665, Turkey
- Microstructural
Analysis Unit, School of Physics and Advanced Materials, University of Technology, Sydney, Altimo NSW 2007,
Australia
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27
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Wu ZW, Chien CT, Liu CY, Yan JY, Lin SY. Recent progress in copolymer-mediated siRNA delivery. J Drug Target 2012; 20:551-60. [DOI: 10.3109/1061186x.2012.699057] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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28
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Lu H, Sun P, Zheng Z, Yao X, Wang X, Chang FC. Reduction-sensitive rapid degradable poly(urethane-urea)s based on cystine. Polym Degrad Stab 2012. [DOI: 10.1016/j.polymdegradstab.2011.12.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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29
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The improvement of anti-proliferation activity against breast cancer cell line of thioguanine by gold nanoparticles. Med Chem Res 2012. [DOI: 10.1007/s00044-012-0030-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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30
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Nelson CE, Gupta MK, Adolph EJ, Shannon JM, Guelcher SA, Duvall CL. Sustained local delivery of siRNA from an injectable scaffold. Biomaterials 2011; 33:1154-61. [PMID: 22061489 DOI: 10.1016/j.biomaterials.2011.10.033] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 10/12/2011] [Indexed: 12/23/2022]
Abstract
Controlled gene silencing technologies have significant, unrealized potential for use in tissue regeneration applications. The design described herein provides a means to package and protect siRNA within pH-responsive, endosomolytic micellar nanoparticles (si-NPs) that can be incorporated into nontoxic, biodegradable, and injectable polyurethane (PUR) tissue scaffolds. The si-NPs were homogeneously incorporated throughout the porous PUR scaffolds, and they were shown to be released via a diffusion-based mechanism for over three weeks. The siRNA-loaded micelles were larger but retained nanoparticulate morphology of approximately 100 nm diameter following incorporation into and release from the scaffolds. PUR scaffold releasate collected in vitro in PBS at 37 °C for 1-4 days was able to achieve dose-dependent siRNA-mediated silencing with approximately 50% silencing achieved of the model gene GAPDH in NIH3T3 mouse fibroblasts. This promising platform technology provides both a research tool capable of probing the effects of local gene silencing and a potentially high-impact therapeutic approach for sustained, local silencing of deleterious genes within tissue defects.
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Affiliation(s)
- Christopher E Nelson
- Biomedical Engineering, Vanderbilt University, 5824 Stevenson Center, PMB 351631, 2301 Vanderbilt Place, Nashville, TN 37235-1631, USA
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31
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Nam JA, Al-Nahain A, Hong S, Lee KD, Lee H, Park SY. Synthesis and Characterization of a Multi-Sensitive Crosslinked Injectable Hydrogel Based on Pluronic. Macromol Biosci 2011. [DOI: 10.1002/mabi.201100265] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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32
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Convertine AJ, Diab C, Prieve M, Paschal A, Hoffman AS, Johnson PH, Stayton PS. pH-responsive polymeric micelle carriers for siRNA drugs. Biomacromolecules 2010; 11:2904-11. [PMID: 20886830 DOI: 10.1021/bm100652w] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The ability of small interfering RNA (siRNA) to efficiently silence the expression of specific genes provides the basis for exciting new therapies based on RNA interference (RNAi). The efficient intracellular delivery of siRNA from cell uptake through the endosomal trafficking pathways into the cytoplasm remains a significant challenge. Previously we described the synthesis of a new family of diblock copolymer siRNA carriers using controlled reversible addition-fragmentation chain transfer (RAFT) polymerization. The carriers were composed of a positively charged block of dimethylaminoethyl methacrylate (DMAEMA) to mediate siRNA binding and a second pH-responsive endosome releasing block composed of DMAEMA and propylacrylic acid (PAA) in roughly equimolar ratios and butyl methacylate (BMA). Here we describe the development of a new generation of siRNA delivery polymers based on this design that exhibit enhanced transfection efficiency and low cytotoxicity. This design incorporates a longer endosomolytic block with increased hydrophobic content to induce micelle formation. These polymers spontaneously form spherical micelles in the size range of 40 nm with CMC (critical micelle concentration) values of approximately 2 μg/mL based on dynamic light scattering (DLS), (1)H NMR, electron microscopy, and selective partitioning of the small molecule pyrene into the hydrophobic micelle core. The siRNA binding to the cationic shell block did not perturb micelle stability or significantly increase particle size. The self-assembly of the diblock copolymers into particles was shown to provide a significant enhancement in mRNA knockdown at siRNA concentrations as low as 12.5 nM. Under these conditions, the micelle-based systems showed an 89% reduction in GAPDH mRNA levels as compared to only 23% (10 nM siRNA) for the nonmicelle system. The reduction in mRNA levels becomes nearly quantitative as the siRNA concentration is increased to 25 nM and higher. Flow cytometry analysis of fluorescent-labeled siRNA showed uptake in 90% of cells and a 3-fold increase in siRNA per cell compared to a standard lipid transfection agent. These results demonstrate the potential utility of this carrier design for siRNA drug delivery.
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Affiliation(s)
- A J Convertine
- Department of Bioengineering, University of Washington, Seattle Washington 98195, and PhaseRx, Inc., 410 West Harrison Street, Suite 300, Seattle Washington 98119
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33
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Zhang M, Xue YN, Liu M, Zhuo RX, Huang SW. Biocleavable Polycationic Micelles as Highly Efficient Gene Delivery Vectors. NANOSCALE RESEARCH LETTERS 2010; 5:1804-1811. [PMID: 21124632 PMCID: PMC2964480 DOI: 10.1007/s11671-010-9716-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2010] [Accepted: 07/26/2010] [Indexed: 05/30/2023]
Abstract
An amphiphilic disulfide-containing polyamidoamine was synthesized by Michael-type polyaddition reaction of piperazine to equimolar N, N'-bis(acryloyl)cystamine with 90% yield. The polycationic micelles (198 nm, 32.5 mV), prepared from the amphiphilic polyamidoamine by dialysis method, can condense foreign plasmid DNA to form nanosized polycationic micelles/DNA polyelectrolyte complexes with positive charges, which transfected 293T cells with high efficiency. Under optimized conditions, the transfection efficiencies of polycationic micelles/DNA complexes are comparable to, or even higher than that of commercially available branched PEI (Mw 25 kDa).
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Affiliation(s)
- Min Zhang
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Ya-Nan Xue
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Min Liu
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Ren-Xi Zhuo
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Shi-Wen Huang
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, 430072, People’s Republic of China
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34
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Henry SM, Convertine AJ, Benoit DSW, Hoffman AS, Stayton PS. End-functionalized polymers and junction-functionalized diblock copolymers via RAFT chain extension with maleimido monomers. Bioconjug Chem 2009; 20:1122-8. [PMID: 19480416 DOI: 10.1021/bc800426d] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new strategy is described for functionalizing the omega-terminal end of polymers synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization that provides spatially controlled bioconjugation sites. Traditional methods for preparing omega-functional polymers require the reduction of the RAFT chain-transfer agent to yield secondary or tertiary thiols of low reactivity or the synthesis of novel chain-transfer agents that contain reactive groups. As an additional strategy, N-substituted maleimido monomers have been used in a modified block polymerization to add a single maleimido unit onto the RAFT polymer with nearly quantitative efficiency. Unique reactive groups contained in the N-substituent are thereby added to the omega-terminal end of the polymer and are subsequently available for conjugation reactions. This technique has been demonstrated using N-(2-aminoethyl)maleimide trifluoroacetate to introduce a single primary amine to the omega-terminus of poly(dimethylaminoethyl methacrylate) and poly(N-isopropyl acrylamide) and to a specialized block copolymer for siRNA delivery. Evidence for retention of functional RAFT endgroups is provided by synthesis results where chain-extended polyDMAEMA (M(n) = 10 600 g/mol, M(w)/M(n) = 1.14) was used as a macro chain transfer agent for the polymerization of styrene, yielding a diblock polymer of low polydispersity (M(n) = 20 300 g/mol, M(w)/M(n) = 1.11). It is thus also possible to construct diblock copolymers with a bioconjugation site precisely located at the junction between the two blocks. The chain-extended polymers are functionalized with an amine-reactive fluorescent dye or folic acid at conjugation efficiencies of 86 and 94%, respectively. The versatile chain-extension technique described here offers unique opportunities for the synthesis of well-defined polymeric conjugates to molecules of biological and targeting interest.
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Affiliation(s)
- Scott M Henry
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
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35
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Argentiere S, Blasi L, Ciccarella G, Barbarella G, Cingolani R, Gigli G. Synthesis of Poly(acrylic acid) Nanogels and Application in Loading and Release of an Oligothiophene Fluorophore and Its Bovine Serum Albumin Conjugate. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/masy.200950709] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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36
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Klaikherd A, Nagamani C, Thayumanavan S. Multi-stimuli sensitive amphiphilic block copolymer assemblies. J Am Chem Soc 2009; 131:4830-8. [PMID: 19290632 PMCID: PMC2693022 DOI: 10.1021/ja809475a] [Citation(s) in RCA: 471] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Stimuli-responsive polymers are arguably the most widely considered systems for a variety of applications in biomedical arena. We report here a novel triple stimuli sensitive block copolymer assembly that responds to changes in temperature, pH and redox potential. Our block copolymer design constitutes an acid-sensitive THP-protected HEMA as the hydrophobic part and a temperature-sensitive PNIPAM as the hydrophilic part with an intervening disulfide bond. The micellar properties and the release kinetics of the encapsulated guest molecule in response to one stimulus as well as combinations of stimuli have been evaluated. Responsiveness to combination of stimuli not only allows for fine-tuning the guest molecule release kinetics, but also provides the possibility of achieving location-specific delivery.
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Affiliation(s)
- Akamol Klaikherd
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003
| | | | - S. Thayumanavan
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003
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37
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Meng F, Hennink WE, Zhong Z. Reduction-sensitive polymers and bioconjugates for biomedical applications. Biomaterials 2009; 30:2180-98. [DOI: 10.1016/j.biomaterials.2009.01.026] [Citation(s) in RCA: 939] [Impact Index Per Article: 62.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 01/13/2009] [Indexed: 11/24/2022]
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38
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Convertine AJ, Benoit DSW, Duvall CL, Hoffman AS, Stayton PS. Development of a novel endosomolytic diblock copolymer for siRNA delivery. J Control Release 2009; 133:221-9. [PMID: 18973780 PMCID: PMC3110267 DOI: 10.1016/j.jconrel.2008.10.004] [Citation(s) in RCA: 313] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 09/11/2008] [Accepted: 10/05/2008] [Indexed: 12/27/2022]
Abstract
The gene knockdown activity of small interfering RNA (siRNA) has led to their use as target validation tools and as potential therapeutics for a variety of diseases. The delivery of these double-stranded RNA macromolecules has proven to be challenging, however, and in many cases, is a barrier to their deployment. Here we report the development of a new diblock copolymer family that was designed to enhance the systemic and intracellular delivery of siRNA. These diblock copolymers were synthesized using the controlled reversible addition fragmentation chain transfer polymerization (RAFT) method and are composed of a positively-charged block of dimethylaminoethyl methacrylate (DMAEMA) to mediate siRNA condensation, and a second endosomal-releasing block composed of DMAEMA and propylacrylic acid (PAA) in roughly equimolar ratios, together with butyl methacylate (BMA). A related series of diblock compositions were characterized, with the cationic block kept constant, and with the ratio of DMAEMA and PAA to BMA varied. These carriers became sharply hemolytic at endosomal pH regimes, with increasing hemolytic activity seen as the percentage of BMA in the second block was systematically increased. The diblock copolymers condensed siRNA into 80-250 nm particles with slightly positive Zeta potentials. SiRNA-mediated knockdown of a model protein, namely glyceraldehyde 3-phosphate dehydrogenase (GAPDH), in HeLa cells generally followed the hemolytic activity trends, with the most hydrophobic second block (highest BMA content) exhibiting the best knockdown. This pH-responsive carrier designed to mediate endosomal release shows significant promise for the intracellular delivery of siRNA.
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39
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Gauthier M, Gibson M, Klok HA. Synthesis of Functional Polymers by Post-Polymerization Modification. Angew Chem Int Ed Engl 2008; 48:48-58. [DOI: 10.1002/anie.200801951] [Citation(s) in RCA: 681] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Gauthier M, Gibson M, Klok HA. Synthese funktioneller Polymere durch polymeranaloge Reaktionen. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200801951] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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41
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Jia Z, Wong L, Davis TP, Bulmus V. One-pot conversion of RAFT-generated multifunctional block copolymers of HPMA to doxorubicin conjugated acid- and reductant-sensitive crosslinked micelles. Biomacromolecules 2008; 9:3106-13. [PMID: 18844406 DOI: 10.1021/bm800657e] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
N-(2-Hydroxypropyl)methacrylamide (HPMA) containing polymers that are widely used as anticancer drug carriers. We have synthesized new amphiphilic block copolymers of HPMA with a functional monomer 2-(2-pyridyldisulfide)ethylmethacrylate (PDSM) via reversible addition-fragmentation chain transfer (RAFT) polymerization. In a one-pot reaction, the versatility of PDS groups on poly(PDSM)- b-poly(HPMA) was used to conjugate an anticancer drug, doxorubicin (DOX), and also simultaneously crosslink the micellar assemblies via acid-cleavable hydrazone bonds and reducible disulfide bonds. DOX-conjugated crosslinked micelles with an average diameter of approximately 60 nm were observed to be formed in aqueous medium. Disintegration of the micelles into unimers in the presence of a disulfide reducing agent confirmed the crosslinking via disulfide bonds. While the release of DOX from the crosslinked micelles at pH 5.0 was faster compared to the release at pH 7.4, a high proportion of released DOX was found to retain the original active structure. Overall results demonstrate the simplicity and the versatility of the poly(PDSM)- b-poly(HPMA) system, which are potentially important in the design of new generation of polymer therapeutics.
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Affiliation(s)
- Zhongfan Jia
- Centre for Advanced Macromolecular Design, School of Chemical Sciences and Engineering, The University of New South Wales, Sydney 2052, NSW, Australia
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42
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Breunig M, Bauer S, Goepferich A. Polymers and nanoparticles: Intelligent tools for intracellular targeting? Eur J Pharm Biopharm 2008; 68:112-28. [PMID: 17804211 DOI: 10.1016/j.ejpb.2007.06.010] [Citation(s) in RCA: 165] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 05/31/2007] [Accepted: 06/06/2007] [Indexed: 01/17/2023]
Abstract
In recent years, a new generation of drugs has entered the pharmaceutical market. Some are more potent, but some are also more toxic and thus, therapeutical efficacy may be hindered, and severe side effects may be observed, unless they are delivered to their assigned place of effect. Those targets are not only certain cell types, moreover, in cancer therapy for example, some drugs even have to be targeted to a specific cell organelle. Those targets in eukaryotic cells include among others endo- and lysosomes, mitochondria, the so-called power plants of the cells, and the biggest compartment with almost all the genetic information, the nucleus. In this review, we describe how the drugs can be directed to specific subcellular organelles and focus especially on synthetic polymers and nanoparticles as their carriers. Furthermore, we portray the progress that has been accomplished in recent years in the field of designing the carriers for efficient delivery into these target structures. Yet, we do not fail to mention the obstacles that still exist and are preventing polymeric and nanoparticular drug carrier systems from their broad application in humans.
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Affiliation(s)
- M Breunig
- Department of Pharmaceutical Technology, University of Regensburg, Universitaetstrasse 31, Regensburg, Germany
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Chen J, Huang SW, Lin WH, Zhuo RX. Tunable film degradation and sustained release of plasmid DNA from cleavable polycation/plasmid DNA multilayers under reductive conditions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2007; 3:636-43. [PMID: 17351989 DOI: 10.1002/smll.200600301] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The controllable and sustained release of DNA from the surfaces of biomaterials or biomedical devices represents a new method for localized gene delivery. We report the synthesis of a novel polycation containing disulfide bonds in its backbone and the fabrication of polycation/plasmid DNA multilayered thin films by layer-by-layer assembly. The films are very stable during preparation and in storage, however, they gradually degrade and release the incorporated DNA when incubated in PBS buffer containing dithiothreitol (DTT), which results from the degradation of a disulfide-contained polymer under reductive conditions. The film degradation rate and DNA release rate can be tuned by the concentration of reducing agent. This approach will be useful in gene therapy and tissue engineering by controlled administration of therapeutic DNA deposited on the surface of implantable biomedical devices or tissue engineering scaffolds.
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Affiliation(s)
- Jun Chen
- Key Laboratory of Biomedical Polymers, Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, PR China
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Schmaljohann D. Thermo- and pH-responsive polymers in drug delivery. Adv Drug Deliv Rev 2006; 58:1655-1670. [PMID: 17125884 DOI: 10.1081/e-ebppc-120050042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Accepted: 09/29/2006] [Indexed: 05/27/2023]
Abstract
Stimuli-responsive polymers show a sharp change in properties upon a small or modest change in environmental condition, e.g. temperature, light, salt concentration or pH. This behaviour can be utilised for the preparation of so-called 'smart' drug delivery systems, which mimic biological response behaviour to a certain extent. The possible environmental conditions to use for this purpose are limited due to the biomedical setting of drug delivery as application. Different organs, tissues and cellular compartments may have large differences in pH, which makes the pH a suitable stimulus. Therefore the majority of examples, discussed in this paper, deal with pH-responsive drug delivery system. Thermo-responsive polymer is also covered to a large extent, as well as double-responsive system. The physico-chemical behaviour underlying the phase transition will be discussed in brief. Then selected examples of applications are described.
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Affiliation(s)
- Dirk Schmaljohann
- Centre for Polymer Therapeutics, Welsh School of Pharmacy, Cardiff University and Cardiff Institute of Tissue Engineering and Repair (CITER), Redwood Building, King Edward VII Avenue, Cardiff, CF10 3XF, Wales, UK.
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You YZ, Hong CY, Pan CY. Functionalization of Carbon Nanotubes with Well-Defined Functional Polymers via Thiol-Coupling Reaction. Macromol Rapid Commun 2006. [DOI: 10.1002/marc.200600573] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Chan Y, Bulmus V, Zareie MH, Byrne FL, Barner L, Kavallaris M. Acid-cleavable polymeric core–shell particles for delivery of hydrophobic drugs. J Control Release 2006; 115:197-207. [PMID: 16996635 DOI: 10.1016/j.jconrel.2006.07.025] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 06/09/2006] [Accepted: 07/25/2006] [Indexed: 11/17/2022]
Abstract
Here we describe the combined use of acid-labile microgel approach and RAFT-mediated seeded dispersion polymerization technique to prepare an acid-cleavable core-shell like polymeric colloidal system for the delivery of hydrophobic drugs at slightly acidic sites. A new bisacrylate acetal crosslinker was copolymerized with n-butyl acrylate (BA) in the presence of a RAFT agent using a dispersion polymerization technique, which yielded crosslinked spherical particles with the size ranging between 150 and 500 nm. The particles were cleaved in a pH-dependent manner similar to the acid-labile hydrolysis behaviour of the crosslinker. In order to mask the hydrophobic surface of the particles, polyethylene glycol acrylate (PEG-A) was grafted onto poly(BA) seed particles via the RAFT agent groups on the particle surface. The acidic-site selective delivery potential of the poly(BA)-g-poly(PEG-A) particles was assessed in-vitro using a lipophilic fluorescent dye as a model hydrophobic drug. Ca. 73% and 34% of the total dye loaded in the particles was found to be released at pH 5.0 and 7.4 in 24 h, respectively. The growth of human neuroblastoma cells was not affected by the incubation with the core-shell particles and their cleavage by-products up to 3 mg/ml concentration. The physicochemical and the functional features support the potential value of the acid-cleavable poly(BA) core-poly(PEG-A) shell particles as carriers for the delivery of hydrophobic drugs at acidic sites.
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Affiliation(s)
- Yannie Chan
- Centre for Advanced Macromolecular Design, CAMD, School of Chemical Sciences and Engineering, The University of New South Wales, Sydney 2052, NSW, Australia
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Cavallaro G, Campisi M, Licciardi M, Ogris M, Giammona G. Reversibly stable thiopolyplexes for intracellular delivery of genes. J Control Release 2006; 115:322-34. [PMID: 17028038 DOI: 10.1016/j.jconrel.2006.07.027] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 07/18/2006] [Accepted: 07/28/2006] [Indexed: 11/17/2022]
Abstract
Novel polyaspartamide non-viral carriers for gene therapy were synthesized by introducing, on the same polymer backbone, positively charged groups, for electrostatic interactions with DNA, and thiol groups for the formation of disulfide bridges between polymer chains. The introduction of thiols was aimed to have a vector with low redox potential sensitivity: disulfide crosslinking in fact, being stable in extracellular environment, allowed either to have stable complexes in plasma, that can protect DNA from metabolism, or to be reduced inside the cell, where the excess of glutathion in reduced form maintains a low redox potential. The consequent destabilization of the complex after disulfide cleavage can release DNA selectively inside the cells. Alpha,beta-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA) was used as starting polymer being a highly water-soluble synthetic polymer, already proposed with success as therapeutic carrier by our group. In this study, PHEA was firstly functionalised with ethylendiamine, obtaining a well defined copolymer with pendant primary amine groups (PHEA-EDA), to which N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) and 3-(carboxypropyl)trimethyl-ammonium chloride (CPTA) were linked in two subsequent steps, allowing the introduction of thiol and cationic groups respectively. Finally DTT treatment lead to the final PHEA-EDA-SH-CPTA thiopolycation, named PESC. The present work describes the synthesis and characterization of the thiopolycation PESC. 1H NMR spectroscopy detected the derivatization molar degrees in SPDP and CPTA; the formation of DNA complexes (thiopolyplexes), their stability in the presence of polyanions and the ability to release DNA under reductive conditions were studied by agarose gel electrophoresis. DNase II degradation study was carried out to detect the ability of thiopolyplex to stabilize DNA towards enzymatic metabolism. Thiopolyplexes were then characterized by Dynamic Light Scattering (DLS) and Zeta Potential analysis. Finally, in vitro toxicity profile (MTT) and gene transfer efficiency (Luciferase assay) were carried out to evaluate thiopolyplex biocompatibility, safety and efficacy to be used as gene delivery system.
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Affiliation(s)
- Gennara Cavallaro
- Dipartimento di Chimica e Tecnologie Farmaceutiche, Università degli Studi di Palermo Via Archirafi 32, 90123, Palermo - Italy
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Portney NG, Ozkan M. Nano-oncology: drug delivery, imaging, and sensing. Anal Bioanal Chem 2006; 384:620-30. [PMID: 16440195 DOI: 10.1007/s00216-005-0247-7] [Citation(s) in RCA: 346] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2005] [Revised: 11/18/2005] [Accepted: 11/19/2005] [Indexed: 01/16/2023]
Abstract
Innovation in the last decade has endowed nanotechnology with an assortment of tools for delivery, imaging, and sensing in cancer research-stealthy nanoparticle vectors circulating in vivo, assembled with exquisite molecular control, capable of selective tumor targeting and potent delivery of therapeutics; intense and photostable quantum dot-based tumor imaging, enabling multicolor detection of cell receptors with a single optical excitation source; arrays of semiconducting nanowire and carbon nanotube sensor elements for selective multiplexed sensing of cancer markers without the need for probe labeling. These rapidly emerging tools are indicative of a burgeoning field ready to expand into medical applications. This review attempts to outline most of the current nanoparticle toolset for therapeutic release by liposomes, dendrimers, smart polymers, and virus-based systems. Advantages of nanoparticle-based imaging and targeting by use of nanoshells and quantum dots are also explored. Finally, emerging nanoelectronics-based sensing and a global discussion on the utility of each nanoparticle system addresses their fundamental advantages and shortcomings in cancer research.
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Affiliation(s)
- Nathaniel G Portney
- Department of Chemical and Environmental Engineering, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, USA
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Stayton PS, El-Sayed MEH, Murthy N, Bulmus V, Lackey C, Cheung C, Hoffman AS. 'Smart' delivery systems for biomolecular therapeutics. Orthod Craniofac Res 2005; 8:219-25. [PMID: 16022724 DOI: 10.1111/j.1601-6343.2005.00336.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE There is a strong need for drug delivery systems that can deliver biological signals from biomaterials and tissue engineering scaffolds, and a particular need for new delivery systems that can efficiently deliver biomolecules to intracellular targets. Viruses and pathogens have evolved potent molecular machinery that sense the lowered pH gradient of the endosomal compartment and become activated to destabilize the endosomal membrane, thereby enhancing protein or DNA transport to the cytoplasmic compartment. A key feature of many of these biological delivery systems is that they are reversible, so that the delivery systems are not directly toxic. These delivery systems have the ability to change their structural and functional properties and thus display remarkable 'smart' material properties. The objective of this presentation is to review the initial development of smart polymeric carriers that mimic these biological delivery systems and combine similar pH-sensitive, membrane-destabilizing activity for the delivery of therapeutic biomolecules. DESIGN We have developed new 'smart' polymeric carriers to more effectively deliver and broaden the available types of biomolecular therapeutics. The polymers are hydrophilic and stealth-like at physiological pH, but become membrane-destabilizing after uptake into the endosomal compartment where they enhance the release of therapeutic cargo into the cytoplasm. They can be designed to provide a range of pH profiles and membrane-destabilizing activities, allowing their molecular properties to be matched to specific drugs and loading ranges. A versatile set of linker chemistries is available to provide degradable conjugation sites for proteins, nucleic acids, and/or targeting moieties. RESULTS The physical properties of several pH-responsive polymers were examined. The activity and pH profile can be manipulated by controlling the length of hydrophobic alkyl segments. The delivery of poly(propyl acrylic acid) (PPAA)-containing lipoplexes significantly enhanced wound healing through the interconnected effects of altered extracellular matrix organization and greater vascularization. PPAA has also been shown to enhance cytoplasmic delivery of a model protein therapeutic. Polymeric carriers displaying pH-sensitive, membrane-destabilizing activity were also examined. The pH profile is controlled by the choice of the alkylacrylic acid monomer and by the ratio of the carboxylate-containing alkylacrylic acid monomer to alkylacrylate monomer. The membrane destabilizing activity is controlled by the lengths of the alkyl segment on the alkylacrylic acid monomer and the alkylacrylate monomer, as well as by their ratio in the final polymer chains. CONCLUSION The molecular mechanisms that proteins use to sense and destabilize provide interesting paradigms for the development of new polymeric delivery systems that mimic biological strategies for promoting the intracellular delivery of biomolecular drugs. The key feature of these polymers is their ability to directly enhance the intracellular delivery of proteins and DNA, by destabilizing biological membranes in response to vesicular compartment pH changes. The ability to deliver a wide variety of protein and nucleic acid drugs to intracellular compartments from tissue engineering and regenerative scaffolds could greatly enhance control of important processes such as inflammation, angiogenesis, and biomineralization.
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Affiliation(s)
- P S Stayton
- Department of Bioengineering, University of Washington, Seattle, WA 98195-2255, USA.
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