1
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Ayub H, Murray RJ, Kuyler GC, Napier-Khwaja F, Gunner J, Dafforn TR, Klumperman B, Poyner DR, Wheatley M. GPCRs in the round: SMA-like copolymers and SMALPs as a platform for investigating GPCRs. Arch Biochem Biophys 2024; 754:109946. [PMID: 38395122 DOI: 10.1016/j.abb.2024.109946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/21/2024] [Accepted: 02/20/2024] [Indexed: 02/25/2024]
Abstract
G-protein-coupled receptors (GPCRs) are the largest family of membrane proteins, regulate a plethora of physiological responses and are the therapeutic target for 30-40% of clinically-prescribed drugs. They are integral membrane proteins deeply embedded in the plasma membrane where they activate intracellular signalling via coupling to G-proteins and β-arrestin. GPCRs are in intimate association with the bilayer lipids and that lipid environment regulates the signalling functions of GPCRs. This complex lipid 'landscape' is both heterogeneous and dynamic. GPCR function is modulated by bulk membrane properties including membrane fluidity, microdomains, curvature, thickness and asymmetry but GPCRs are also regulated by specific lipid:GPCR binding, including cholesterol and anionic lipids. Understanding the molecular mechanisms whereby GPCR signalling is regulated by lipids is a very active area of research currently. A major advance in membrane protein research in recent years was the application of poly(styrene-co-maleic acid) (SMA) copolymers. These spontaneously generate SMA lipid particles (SMALPs) encapsulating membrane protein in a nano-scale disc of cell membrane, thereby removing the historical need for detergent and preserving lipid:GPCR interaction. The focus of this review is how GPCR-SMALPs are increasing our understanding of GPCR structure and function at the molecular level. Furthermore, an increasing number of 'second generation' SMA-like copolymers have been reported recently. These are reviewed from the context of increasing our understanding of GPCR molecular mechanisms. Moreover, their potential as a novel platform for downstream biophysical and structural analyses is assessed and looking ahead, the translational application of SMA-like copolymers to GPCR drug discovery programmes in the future is considered.
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Affiliation(s)
- Hoor Ayub
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK.
| | - Rebecca J Murray
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK; Department of Chemistry and Polymer Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - Gestél C Kuyler
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK; Department of Chemistry and Polymer Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | | | - Joseph Gunner
- School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - Tim R Dafforn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Bert Klumperman
- Department of Chemistry and Polymer Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - David R Poyner
- School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - Mark Wheatley
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
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2
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Dreyer R, Pfukwa R, Barth S, Hunter R, Klumperman B. The Evolution of SNAP-Tag Labels. Biomacromolecules 2023; 24:517-530. [PMID: 36607253 DOI: 10.1021/acs.biomac.2c01238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The conjugation of proteins with synthetic molecules can be conducted in many different ways. In this Perspective, we focus on tag-based techniques and specifically on the SNAP-tag technology. The SNAP-tag technology makes use of a fusion protein between a protein of interest and an enzyme tag that enables the actual conjugation reaction. The SNAP-tag is based on the O6-alkylguanine-DNA alkyltransferase (AGT) enzyme and is optimized to react selectively with O6-benzylguanine (BG) substrates. BG-containing dye derivatives have frequently been used to introduce a fluorescent tag to a specific protein. We believe that the site-specific conjugation of polymers to proteins can significantly benefit from the SNAP-tag technology. Especially, polymers synthesized via reversible deactivation radical polymerization allow for the facile introduction of a BG end group to enable SNAP-tag conjugation.
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Affiliation(s)
- Rudolf Dreyer
- Stellenbosch University, Department of Chemistry and Polymer Science, Private Bag X1, Matieland 7602, South Africa
| | - Rueben Pfukwa
- Stellenbosch University, Department of Chemistry and Polymer Science, Private Bag X1, Matieland 7602, South Africa
| | - Stefan Barth
- Medical Biotechnology and Immunotherapy Research Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Observatory 7935, South Africa.,South African Research Chair in Cancer Biotechnology, Department of Integrative Biomedical Sciences, Faculty of Health Sciences, University of Cape Town, Observatory 7935, South Africa
| | - Roger Hunter
- Department of Chemistry, Faculty of Science, University of Cape Town, Rondebosch 7701, South Africa
| | - Bert Klumperman
- Stellenbosch University, Department of Chemistry and Polymer Science, Private Bag X1, Matieland 7602, South Africa
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3
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Ball LE, Pfukwa R, Siqueira RP, Mosqueira VCF, Klumperman B. PLA‐
b
‐SMA as an Amphiphilic Diblock Copolymer for Encapsulation of Lipophilic Cargo. MACROMOL CHEM PHYS 2022. [DOI: 10.1002/macp.202200212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Lauren E. Ball
- Department of Chemistry and Polymer Science Stellenbosch University Private Bag X1 Matieland 7602 South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science Stellenbosch University Private Bag X1 Matieland 7602 South Africa
| | - Raoni P. Siqueira
- School of Pharmacy Federal University of Ouro Preto Ouro Preto Minas Gerais 35400‐000 Brazil
| | - Vanessa C. F. Mosqueira
- School of Pharmacy Federal University of Ouro Preto Ouro Preto Minas Gerais 35400‐000 Brazil
| | - Bert Klumperman
- Department of Chemistry and Polymer Science Stellenbosch University Private Bag X1 Matieland 7602 South Africa
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4
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Hutchinson RA, Klumperman B, Russell GT, Van Herk AM. The contributions of
Prof. Kenneth F. O'Driscoll
to radical copolymerization kinetics. CAN J CHEM ENG 2022. [DOI: 10.1002/cjce.24137] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Robin A. Hutchinson
- Department of Chemical Engineering Dupuis Hall, Queen's University Kingston Ontario Canada
| | - Bert Klumperman
- Department of Chemistry and Polymer Science Stellenbosch University Stellenbosch South Africa
| | - Gregory T. Russell
- School of Physical and Chemical Sciences University of Canterbury Christchurch New Zealand
| | - Alexander M. Van Herk
- Institute of Chemical and Engineering Sciences Division Functional Molecules and Polymers Singapore
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5
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Giliomee J, du Toit LC, Klumperman B, Choonara YE. Investigation of the 3D Printability of Covalently Cross-Linked Polypeptide-Based Hydrogels. ACS Omega 2022; 7:7556-7571. [PMID: 35284718 PMCID: PMC8908529 DOI: 10.1021/acsomega.1c05873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
The 3D printability of poly(l-lysine-ran-l-alanine) and four-arm poly(ethylene glycol) (P(KA)/4-PEG) hydrogels as 3D biomaterial inks was investigated using two approaches to develop P(KA)/4-PEG into 3D biomaterial inks. Only the "composite microgel" inks were 3D printable. In this approach, P(KA)/4-PEG hydrogels were processed into microparticles and incorporated into a polymer solution to produce a composite microgel paste. Polymer solutions composed of either 4-arm PEG-acrylate (4-PEG-Ac), chitosan (CS), or poly(vinyl alcohol) (PVA) were used as the matrix material for the composite paste. The three respective composite microgel inks displayed good 3D printability in terms of extrudability, layer-stacking ability, solidification mechanism, and 3D print fidelity. The biocompatibility of P(KA)/4-PEG hydrogels was retained in the 3D printed scaffolds, and the biofunctionality of bioinert 4-PEG and PVA hydrogels was enhanced. CS-P(KA)/4-PEG inks demonstrated excellent 3D printability and proved highly successful in printing scaffolds with a narrow strand diameter (∼200 μm) and narrow strand spacing (∼500 μm) while the integrity of the vertical and horizontal pores was maintained. Using different needle IDs and strand spacing, certain physical properties of the hydrogels could be tuned, while the 3D printed porosity was kept constant. This included the surface area to volume ratio, the macropore sizes, and the mechanical properties. The scaffolds demonstrated adequate adhesion and spreading of NIH 3T3 fibroblasts seeded on the scaffold surfaces for 4 days. Consequently, the scaffolds were considered suitable for potential applications in wound healing, as well as other soft tissue engineering applications. Apart from the contribution to new 3D biomaterial inks, this work also presented a new and facile method of processing covalently cross-linked hydrogels into 3D printed scaffolds. This could potentially "unlock" the 3D printability of biofunctional hydrogels, which are generally excluded from 3D printing applications.
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Affiliation(s)
- Johnel Giliomee
- Wits
Advanced Drug Delivery Platform Research Unit, Department of Pharmacy
and Pharmacology, School of Therapeutic Sciences, Faculty of Health
Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South
Africa
| | - Lisa C. du Toit
- Wits
Advanced Drug Delivery Platform Research Unit, Department of Pharmacy
and Pharmacology, School of Therapeutic Sciences, Faculty of Health
Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South
Africa
| | - Bert Klumperman
- Department
of Chemistry and Polymer Science, Faculty of Science, Stellenbosch University, De Beers Street, Stellenbosch 7600, South Africa
| | - Yahya E. Choonara
- Wits
Advanced Drug Delivery Platform Research Unit, Department of Pharmacy
and Pharmacology, School of Therapeutic Sciences, Faculty of Health
Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South
Africa
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6
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Fang H, Sha Y, Yang L, Jiang J, Yin L, Li J, Li B, Klumperman B, Zhong Z, Meng F. Macrophage-Targeted Hydroxychloroquine Nanotherapeutics for Rheumatoid Arthritis Therapy. ACS Appl Mater Interfaces 2022; 14:8824-8837. [PMID: 35156814 DOI: 10.1021/acsami.1c23429] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease with unclear pathogenesis. Hydroxychloroquine (HCQ), despite its moderate anti-RA efficacy, is among the few clinical drugs used for RA therapy. Macrophages reportedly play a vital role in RA. Here, we designed and explored macrophage-targeted HCQ nanotherapeutics based on mannose-functionalized polymersomes (MP-HCQ) for RA therapy. Notably, MP-HCQ exhibited favorable properties of less than 50 nm size, glutathione-accelerated HCQ release, and M1 phenotype macrophage (M1M) targetability, leading to repolarization of macrophages to anti-inflammatory M2 phenotype (M2M), reduced secretion of pro-inflammatory cytokines (IL-6), and upregulation of anti-inflammatory cytokines (IL-10). The therapeutic studies in the zymosan-induced RA (ZIA) mouse model showed marked accumulation of MP-HCQ in the inflammation sites, ameliorated symptoms of RA joints, significantly reduced IL-6, TNF-α, and IL-1β, and increased IL-10 and TGF-β compared with free HCQ. The analyses of RA joints disclosed greatly amplified M2M and declined mature DCs, CD4+ T cells, and CD8+ T cells. In accordance, MP-HCQ significantly reduced the damage of RA joints, cartilages, and bones compared to free HCQ and non-targeted controls. Macrophage-targeted HCQ nanotherapeutics therefore appears as a highly potent treatment for RA.
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Affiliation(s)
- Hanghang Fang
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Soochow University, Suzhou 215123, P. R. China
- College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, P. R. China
| | - Yongjie Sha
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Soochow University, Suzhou 215123, P. R. China
| | - Liang Yang
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Soochow University, Suzhou 215123, P. R. China
| | - Jingjing Jiang
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Soochow University, Suzhou 215123, P. R. China
| | - Lichen Yin
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China
| | - Jiaying Li
- Orthopedic Institute, Soochow University, Suzhou 215007, PR China
| | - Bin Li
- Orthopedic Institute, Soochow University, Suzhou 215007, PR China
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Zhiyuan Zhong
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Soochow University, Suzhou 215123, P. R. China
- College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, P. R. China
| | - Fenghua Meng
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Soochow University, Suzhou 215123, P. R. China
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7
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Carter JG, Pfukwa R, Riley L, Tucker JHR, Rodger A, Dafforn TR, Klumperman B. Linear Dichroism Activity of Chiral Poly( p-Aryltriazole) Foldamers. ACS Omega 2021; 6:33231-33237. [PMID: 34901675 PMCID: PMC8656205 DOI: 10.1021/acsomega.1c06139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 11/15/2021] [Indexed: 05/04/2023]
Abstract
Controllable higher-order assembly is a central aim of macromolecular chemistry. An essential challenge to developing these molecules is improving our understanding of the structures they adopt under different conditions. Here, we demonstrate how flow linear dichroism (LD) spectroscopy is used to provide insights into the solution structure of a chiral, self-assembled fibrillar foldamer. Poly(para-aryltriazole)s fold into different structures depending on the monomer geometry and variables such as solvent and ionic strength. LD spectroscopy provides a simple route to determine chromophore alignment in solution and is generally used on natural molecules or molecular assemblies such as DNA and M13 bacteriophage. In this contribution, we show that LD spectroscopy is a powerful tool in the observation of self-assembly processes of synthetic foldamers when complemented by circular dichroism, absorbance spectroscopy, and microscopy. To that end, poly(para-aryltriazole)s were aligned in a flow field under different solvent conditions. The extended aromatic structures in the foldamer give rise to a strong LD signal that changes in sign and in intensity with varying solvent conditions. A key advantage of LD is that it only detects the large assemblies, thus removing background due to monomers and small oligomers.
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Affiliation(s)
- Jake G. Carter
- School
of Chemistry, University of Birmingham, Edgbaston, Birmingham, West Midlands B15 2TT, U.K.
- School
of Biosciences, University of Birmingham, Edgbaston, Birmingham, West Midlands B15 2TT, U.K.
| | - Rueben Pfukwa
- Department
of Chemistry and Polymer Sciences, Stellenbosch
University, Private Bag X1, Matieland 7602, South Africa
| | - Liam Riley
- School
of Biosciences, University of Birmingham, Edgbaston, Birmingham, West Midlands B15 2TT, U.K.
- School
of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, U.K.
| | - James H. R. Tucker
- School
of Chemistry, University of Birmingham, Edgbaston, Birmingham, West Midlands B15 2TT, U.K.
| | - Alison Rodger
- Department
of Molecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Timothy R. Dafforn
- School
of Biosciences, University of Birmingham, Edgbaston, Birmingham, West Midlands B15 2TT, U.K.
| | - Bert Klumperman
- Department
of Chemistry and Polymer Sciences, Stellenbosch
University, Private Bag X1, Matieland 7602, South Africa
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8
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Grime RL, Logan RT, Nestorow SA, Sridhar P, Edwards PC, Tate CG, Klumperman B, Dafforn TR, Poyner DR, Reeves PJ, Wheatley M. Differences in SMA-like polymer architecture dictate the conformational changes exhibited by the membrane protein rhodopsin encapsulated in lipid nano-particles. Nanoscale 2021; 13:13519-13528. [PMID: 34477756 PMCID: PMC8359648 DOI: 10.1039/d1nr02419a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Membrane proteins are of fundamental importance to cellular processes and nano-encapsulation strategies that preserve their native lipid bilayer environment are particularly attractive for studying and exploiting these proteins. Poly(styrene-co-maleic acid) (SMA) and related polymers poly(styrene-co-(N-(3-N',N'-dimethylaminopropyl)maleimide)) (SMI) and poly(diisobutylene-alt-maleic acid) (DIBMA) have revolutionised the study of membrane proteins by spontaneously solubilising membrane proteins direct from cell membranes within nanoscale discs of native bilayer called SMA lipid particles (SMALPs), SMILPs and DIBMALPs respectively. This systematic study shows for the first time, that conformational changes of the encapsulated protein are dictated by the solubilising polymer. The photoactivation pathway of rhodopsin (Rho), a G-protein-coupled receptor (GPCR), comprises structurally-defined intermediates with characteristic absorbance spectra that revealed conformational restrictions with styrene-containing SMA and SMI, so that photoactivation proceeded only as far as metarhodopsin-I, absorbing at 478 nm, in a SMALP or SMILP. In contrast, full attainment of metarhodopsin-II, absorbing at 382 nm, was observed in a DIBMALP. Consequently, different intermediate states of Rho could be generated readily by simply employing different SMA-like polymers. Dynamic light-scattering and analytical ultracentrifugation revealed differences in size and thermostability between SMALP, SMILP and DIBMALP. Moreover, encapsulated Rho exhibited different stability in a SMALP, SMILP or DIBMALP. Overall, we establish that SMA, SMI and DIBMA constitute a 'toolkit' of solubilising polymers, so that selection of the appropriate solubilising polymer provides a spectrum of useful attributes for studying membrane proteins.
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Affiliation(s)
- Rachael L Grime
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK
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9
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Xia Y, Wei J, Zhao S, Guo B, Meng F, Klumperman B, Zhong Z. Systemic administration of polymersomal oncolytic peptide LTX-315 combining with CpG adjuvant and anti-PD-1 antibody boosts immunotherapy of melanoma. J Control Release 2021; 336:262-273. [PMID: 34174350 DOI: 10.1016/j.jconrel.2021.06.032] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 06/02/2021] [Accepted: 06/21/2021] [Indexed: 01/15/2023]
Abstract
Oncolytic peptide LTX-315 while showing clinical promise in treating solid tumors is limited to intratumoral administration, which is not applicable for inaccessible or metastatic tumors. The cationic and amphipathic nature of oncolytic peptides engenders formidable challenges to developing systems for their systemic delivery. Here, we describe cRGD-functionalized chimaeric polymersomes (cRGD-CPs) as a robust systemic delivery vehicle for LTX-315, which in combination with CpG adjuvant and anti-PD-1 boost immunotherapy of malignant B16F10 melanoma in mice. cRGD-CPs containing 14.9 wt% LTX-315 (cRGD-CPs-L) exhibited a size of 53 nm, excellent serum stability, and strong and selective killing of B16F10 cells (versus L929 fibroblasts) in vitro, which provoked similar immunogenic effects to free LTX-315 as revealed by release of danger-associated molecular pattern molecules. The systemic administration of cRGD-CPs-L gave a notable tumor accumulation of 4.8% ID/g and significant retardation of tumor growth. More interestingly, the treatment of B16F10 tumor-bearing mice was further boosted by co-administration of polymersomal CpG and anti-PD-1 antibody, in which two out of seven mice were cured as a result of strong immune response and long-term immune memory protection. The immunotherapeutic effect was evidenced by secretion of IL-6, IFN-γ and TNF-α, tumor infiltration of CD8+ CTLs and Th, and induction of TEM and TCM in spleen. This study opens a new avenue to oncolytic peptides, which enables durable immunotherapy of tumors via systemic administration.
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Affiliation(s)
- Yifeng Xia
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, PR China
| | - Jingjing Wei
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, PR China
| | - Songsong Zhao
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, PR China
| | - Beibei Guo
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, PR China
| | - Fenghua Meng
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, PR China.
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Zhiyuan Zhong
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, PR China.
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10
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Giliomee J, du Toit LC, Kumar P, Klumperman B, Choonara YE. Evaluation of Composition Effects on the Physicochemical and Biological Properties of Polypeptide-Based Hydrogels for Potential Application in Wound Healing. Polymers (Basel) 2021; 13:polym13111828. [PMID: 34073003 PMCID: PMC8198873 DOI: 10.3390/polym13111828] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/27/2021] [Accepted: 05/27/2021] [Indexed: 11/22/2022] Open
Abstract
In this study, the effect of crosslinking and concentration on the properties of a new library of low-concentration poly(Lys60-ran-Ala40)-based hydrogels for potential application in wound healing was investigated in order to correlate the hydrogel composition with the desired physicochemical and biofunctional properties to expand the assortment of poly-l-lysine (PLL)-based hydrogels suitable for wound healing. Controlled ring-opening polymerization (ROP) and precise hydrogel compositions were used to customize the physicochemical and biofunctional properties of a library of new hydrogels comprising poly(l-lysine-ran-l-alanine) and four-arm poly(ethylene glycol) (P(KA)/4-PEG). The chemical composition and degree of crosslinking via free amine quantification were analyzed for the P(KA)/4-PEG hydrogels. In addition, the rheological properties, pore morphology, swelling behavior and degradation time were characterized. Subsequently, in vitro cell studies for evaluation of the cytotoxicity and cell adhesion were performed. The 4 wt% 1:1 functional molar ratio hydrogel with P(KA) concentrations as low as 0.65 wt% demonstrated low cytotoxicity and desirable cell adhesion towards fibroblasts and thus displayed a desirable combination of properties for wound healing application.
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Affiliation(s)
- Johnel Giliomee
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa; (J.G.); (L.C.d.T.); (P.K.)
| | - Lisa C. du Toit
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa; (J.G.); (L.C.d.T.); (P.K.)
| | - Pradeep Kumar
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa; (J.G.); (L.C.d.T.); (P.K.)
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Faculty of Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa;
| | - Yahya E. Choonara
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa; (J.G.); (L.C.d.T.); (P.K.)
- Correspondence: ; Tel.: +27-11-717-2052
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11
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Jharimune S, Pfukwa R, Chen Z, Anderson J, Klumperman B, Rioux RM. Chemical Identity of Poly( N-vinylpyrrolidone) End Groups Impact Shape Evolution During the Synthesis of Ag Nanostructures. J Am Chem Soc 2021; 143:184-195. [PMID: 33346658 DOI: 10.1021/jacs.0c08528] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ag nanocubes (AgNCs) are predominantly synthesized by the polyol method, where the solvent (ethylene glycol) is considered the reducing agent and poly(N-vinylpyrrolidone) (PVP) the shape-directing agent. An experimental phase diagram for the formation of Ag nanocubes as a function of PVP monomer concentration (Cm) and molecular weight (Mw) demonstrated end groups of PVP impact the final Ag product. Measured rates of the initial Ag+ reduction at different PVP Cm and Mw confirmed the reducing effect originates from end-groups. PVP with well-defined aldehyde and hydroxyl end groups lead to the formation of Ag nanocubes and nanowires respectively, indicating the faster reducing agent formed kinetically preferred nanowires. We demonstrate PVP end-groups induce initial reduction of Ag+ to form seeds followed by autocatalytic reduction of Ag+ by ethylene glycol (and not solvent oxidation products) to form Ag nanostructures. The current study enabled a quantitative description of the role of PVP in nanoparticle shape-control and demonstrates a unique opportunity to design nanostructures by combining nanoparticle synthesis with polymer design to introduce specific physicochemical properties.
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Affiliation(s)
- Suprita Jharimune
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Zhifeng Chen
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Justin Anderson
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Robert M Rioux
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.,Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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12
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Ball LE, Riley LJ, Hadasha W, Pfukwa R, Smith CJI, Dafforn TR, Klumperman B. Influence of DIBMA Polymer Length on Lipid Nanodisc Formation and Membrane Protein Extraction. Biomacromolecules 2020; 22:763-772. [PMID: 33373193 DOI: 10.1021/acs.biomac.0c01538] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Polymer-based lipid nanoparticles like styrene-maleic acid lipid particles have revolutionized the study of membrane proteins. More recently, alternative polymers such as poly(diisobutylene-alt-maleic acid) (DIBMA) have been used in this field. DIBMA is commonly synthesized via conventional radical copolymerization. In order to study the influence of its chain length on lipid nanodisc formation and membrane protein extraction, we synthesized DIBMA with molar masses varying from 1.2-12 kDa via RAFT-mediated polymerization. For molar masses in the range of 3-7 kDa, the rate of lipid nanodisc formation was the highest and similar to those of poly(styrene-co-maleic acid) (SMA) and commercially available DIBMA. ZipA solubilization efficiency was significantly higher than for commercially available DIBMA and similar to SMA (circa 75%). Furthermore, RAFT-made DIBMA with a molar mass of 1.2-3.9 kDa showed a much cleaner separation on SDS-PAGE, without the smearing that is typically seen for SMA and commercially available DIBMA.
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Affiliation(s)
- Lauren E Ball
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Liam J Riley
- School of Life Sciences, The University of Warwick, Gibbet Hill Campus, Coventry CV4 7AL, United Kingdom.,School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Waled Hadasha
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Corinne J I Smith
- School of Life Sciences, The University of Warwick, Gibbet Hill Campus, Coventry CV4 7AL, United Kingdom
| | - Timothy R Dafforn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
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13
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Jokonya S, Langlais M, Leshabane M, Reader PW, Vosloo JA, Pfukwa R, Coertzen D, Birkholtz LM, Rautenbach M, Klumperman B. Poly( N-vinylpyrrolidone) Antimalaria Conjugates of Membrane-Disruptive Peptides. Biomacromolecules 2020; 21:5053-5066. [PMID: 33156615 DOI: 10.1021/acs.biomac.0c01202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The concepts of polymer-peptide conjugation and self-assembly were applied to antimicrobial peptides (AMPs) in the development of a targeted antimalaria drug delivery construct. This study describes the synthesis of α-acetal, ω-xanthate heterotelechelic poly(N-vinylpyrrolidone) (PVP) via reversible addition-fragmentation chain transfer (RAFT)-mediated polymerization, followed by postpolymerization deprotection to yield α-aldehyde, ω-thiol heterotelechelic PVP. A specific targeting peptide, GSRSKGT, for Plasmodium falciparum-infected erythrocytes was used to sparsely decorate the α-chain ends via reductive amination while cyclic decapeptides from the tyrocidine group were conjugated to the ω-chain end via thiol-ene Michael addition. The resultant constructs were self-assembled into micellar nanoaggregates whose sizes and morphologies were determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The in vitro activity and selectivity of the conjugates were evaluated against intraerythrocytic P. falciparum parasites.
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Affiliation(s)
- Simbarashe Jokonya
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Marvin Langlais
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Meta Leshabane
- Department of Biochemistry, Genetics and Microbiology, Institute of Sustainable Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Paul W Reader
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Johan A Vosloo
- BioPep Peptide Group, Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Dina Coertzen
- Department of Biochemistry, Genetics and Microbiology, Institute of Sustainable Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Lyn-Marie Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute of Sustainable Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Marina Rautenbach
- BioPep Peptide Group, Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
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14
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Fortuin L, Leshabane M, Pfukwa R, Coertzen D, Birkholtz LM, Klumperman B. Facile Route to Targeted, Biodegradable Polymeric Prodrugs for the Delivery of Combination Therapy for Malaria. ACS Biomater Sci Eng 2020; 6:6217-6227. [DOI: 10.1021/acsbiomaterials.0c01234] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lisa Fortuin
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Meta Leshabane
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Dina Coertzen
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Lyn-Marie Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
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15
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Cunningham RD, Kopf AH, Elenbaas BOW, Staal BB, Pfukwa R, Killian JA, Klumperman B. Iterative RAFT-Mediated Copolymerization of Styrene and Maleic Anhydride toward Sequence- and Length-Controlled Copolymers and Their Applications for Solubilizing Lipid Membranes. Biomacromolecules 2020; 21:3287-3300. [DOI: 10.1021/acs.biomac.0c00736] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Randy D. Cunningham
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Adrian H. Kopf
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Utrecht University, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Barend O. W. Elenbaas
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Utrecht University, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Bastiaan B.P. Staal
- BASF SE, RAA/AC, E210, Carl-Bosch-Strasse 38, Ludwigshafen am Rhein 67056, Germany
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - J. Antoinette Killian
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Utrecht University, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
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16
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Barnard E, Pfukwa R, Maiz J, Müller AJ, Klumperman B. Synthesis, Structure, and Crystallization Behavior of Amphiphilic Heteroarm Molecular Brushes with Crystallizable Poly(ethylene oxide) and n-Alkyl Side Chains. Macromolecules 2020. [DOI: 10.1021/acs.macromol.9b02473] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Elaine Barnard
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Jon Maiz
- POLYMAT and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal, 3, 20018 Donostia-San Sebastián, Spain
| | - Alejandro J. Müller
- POLYMAT and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal, 3, 20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
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17
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Kargaard A, Sluijter JPG, Klumperman B. Polymeric siRNA gene delivery - transfection efficiency versus cytotoxicity. J Control Release 2019; 316:263-291. [PMID: 31689462 DOI: 10.1016/j.jconrel.2019.10.046] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 10/23/2019] [Accepted: 10/23/2019] [Indexed: 12/13/2022]
Abstract
Within the field of gene therapy, there is a considerable need for the development of non-viral vectors that are able to compete with the efficiency obtained by viral vectors, while maintaining a good toxicity profile and not inducing an immune response within the body. While there have been many reports of possible polymeric delivery systems, few of these systems have been successful in the clinical setting due to toxicity, systemic instability or gene regulation inefficiency, predominantly due to poor endosomal escape and cytoplasmic release. The objective of this review is to provide an overview of previously published polymeric non-coding RNA and, to a lesser degree, oligo-DNA delivery systems with emphasis on their positive and negative attributes, in order to provide insight in the numerous hurdles that still limit the success of gene therapy.
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Affiliation(s)
- Anna Kargaard
- Stellenbosch University, Department of Chemistry and Polymer Science, Private Bag X1, Matieland 7602, South Africa; University Medical Center Utrecht, Experimental Cardiology Laboratory, Department of Cardiology, Division of Heart and Lungs, P.O. Box 85500, 3508 GA, Utrecht, the Netherlands
| | - Joost P G Sluijter
- University Medical Center Utrecht, Experimental Cardiology Laboratory, Department of Cardiology, Division of Heart and Lungs, P.O. Box 85500, 3508 GA, Utrecht, the Netherlands; Utrecht University, the Netherlands
| | - Bert Klumperman
- Stellenbosch University, Department of Chemistry and Polymer Science, Private Bag X1, Matieland 7602, South Africa.
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18
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Heyns IM, Pfukwa R, Bertossi L, Ball LE, Kelland MA, Klumperman B. Thermoresponsive behavior of poly(3-methylene-2-pyrrolidone) derivatives. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2018.10.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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19
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Kopf AH, Xie M, Cunningham R, Koorengevel MC, Jahn H, Dörr JM, Pfukwa R, Klumperman B, Killian AJ. Biological Membrane Solubilization by Styrene-Maleic Acid Copolymers: Importance of Polymer Length. Biophys J 2019. [DOI: 10.1016/j.bpj.2018.11.487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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20
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Cloete WJ, Hayward S, Swart P, Klumperman B. Degradation of Proteins and Starch by Combined Immobilization of Protease, α-Amylase and β-Galactosidase on a Single Electrospun Nanofibrous Membrane. Molecules 2019; 24:molecules24030508. [PMID: 30708952 PMCID: PMC6384644 DOI: 10.3390/molecules24030508] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 01/28/2023] Open
Abstract
Two commercially available enzymes, Dextrozyme (α-amylase) and Esperase (protease), were covalently immobilized on non-woven electrospun poly(styrene-co-maleic anhydride) nanofiber mats with partial retention of their catalytic activity. Immobilization was achieved for the enzymes on their own as well as in different combinations with an additional enzyme, β-galactosidase, on the same non-woven nanofiber mat. This experiment yielded a universal method for immobilizing different combinations of enzymes with nanofibrous mats containing maleic anhydride (MAnh) residues in the polymer backbone.
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Affiliation(s)
- William J Cloete
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Stefan Hayward
- Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Pieter Swart
- Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
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21
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Mbizana S, Hlalele L, Pfukwa R, Du Toit A, Lumkwana D, Loos B, Klumperman B. Synthesis and Cell Interaction of Statistical l-Arginine-Glycine-l-Aspartic Acid Terpolypeptides. Biomacromolecules 2018; 19:3058-3066. [PMID: 29715425 DOI: 10.1021/acs.biomac.8b00620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Copolymerizations and terpolymerizations of N-carboxyanhydrides (NCAs) of glycine (Gly), Nδ-carbobenzyloxy-l-ornithine (Z-Orn), and β-benzyl-l-aspartate (Bz-Asp) were investigated. In situ 1H NMR spectroscopy was used to monitor individual comonomer consumptions during binary and ternary copolymerizations. The six relevant reactivity ratios were determined from copolymerizations of the NCAs of amino acids via nonlinear least-squares curve fitting. The reactivity ratios were subsequently used to maximize the occurrence of the Asp-Gly-Orn ( DGR') sequence in the terpolymers. Terpolymers with variable probability of occurrence of DGR' were prepared in the lab. Subsequently, the ornithine residues on the terpolymers were converted to l-arginine (R) residues via guanidination reaction after removal of the protecting groups. The resulting DGR terpolymers translate to traditional peptides and proteins with variable RGD content, due to the convention in nomenclature that peptides are depicted from N- to C-terminus, whereas the NCA ring-opening polymerization is conducted from C- to N-terminus. The l-arginine containing terpolymers were evaluated for cell interaction, where it was found that neuronal cells display enhanced adhesion and process formation when plated in the presence of statistical DGR terpolymers.
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22
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23
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Affiliation(s)
- Renier Kemp
- Department of Chemistry and Polymer Science; Stellenbosch University; Private Bag X1, Matieland 7602 South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science; Stellenbosch University; Private Bag X1, Matieland 7602 South Africa
| | - Nonjabulo Prudence Gule
- Department of Chemistry and Polymer Science; Stellenbosch University; Private Bag X1, Matieland 7602 South Africa
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24
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Kopf AH, Harmzen N, Dominguez JJ, Koorengevel MC, Pfukwa R, Klumperman B, Killian AJ. Membrane Solubilization by Styrene-Maleic Acid Copolymers: Importance of Polymer Length and Comonomer Sequence. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.2526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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25
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Hall SCL, Tognoloni C, Price GJ, Klumperman B, Edler KJ, Dafforn TR, Arnold T. Influence of Poly(styrene-co-maleic acid) Copolymer Structure on the Properties and Self-Assembly of SMALP Nanodiscs. Biomacromolecules 2017; 19:761-772. [DOI: 10.1021/acs.biomac.7b01539] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stephen C. L. Hall
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 ODE, United Kingdom
| | - Cecilia Tognoloni
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
- ISIS Neutron and Muon Source, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell, Didcot OX11 0QX, United Kingdom
| | - Gareth J. Price
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Division of Polymer Science, Stellenbosch University, De Beers Street, Stellenbosch 7600, South Africa
| | - Karen J. Edler
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Tim R. Dafforn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Thomas Arnold
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 ODE, United Kingdom
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26
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Affiliation(s)
- William J. Cloete
- Stellenbosch University, Private Bag X1, Matieland, 7602, Stellenbosch, South Africa
| | - Bert Klumperman
- Stellenbosch University, Private Bag X1, Matieland, 7602, Stellenbosch, South Africa
| | - Thomas Eugene Cloete
- Stellenbosch University, Private Bag X1, Matieland, 7602, Stellenbosch, South Africa
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28
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Heyns IM, Pfukwa R, Klumperman B. Synthesis, Characterization, and Evaluation of Cytotoxicity of Poly(3-methylene-2-pyrrolidone). Biomacromolecules 2016; 17:1795-800. [DOI: 10.1021/acs.biomac.6b00210] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ingrid M. Heyns
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Rueben Pfukwa
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Bert Klumperman
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
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29
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Rowan SJ, Barner-Kowollik C, Klumperman B, Gaspard P, Grubbs RB, Hillmyer MA, Hutchings LR, Mahanthappa MK, Moatsou D, O’Reilly RK, Ouchi M, Sawamoto M, Lodge TP. Discussion on "Aperiodic Copolymers". ACS Macro Lett 2016; 5:1-3. [PMID: 35668592 DOI: 10.1021/acsmacrolett.5b00758] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In a recent Viewpoint (ACS Macro Lett. 2014, 3, 1020), J.-F. Lutz brought to the community's attention the need for more informative nomenclature, especially with respect to macromolecules with prescribed but not repeating sequences of monomers. Lutz proposes the use of the term "aperiodic" for this situation. In this Viewpoint, we comment on the need for such nomenclature and offer some alternatives for consideration.
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Affiliation(s)
- Stuart J. Rowan
- Department
of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, United States
| | - Christopher Barner-Kowollik
- Preparative
Macromolecular Chemistry, Institut für Technische Chemie und
Polymerchemie, Karlsruhe Institute of Technology (KIT), Engesserstr. 18, 76128 Karlsruhe, Germany
- Institut für
Biologische Grenzflächen, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz
1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Bert Klumperman
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Pierre Gaspard
- Centre
for Nonlinear Phenomena and Complex Systems, Université Libre de Bruxelles (ULB), Campus Plaine Code Postal 231, B-1050 Brussels, Belgium
| | - Robert B. Grubbs
- Chemistry
Department, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Marc A. Hillmyer
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Lian R. Hutchings
- Durham
Centre for Soft Matter, Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Mahesh K. Mahanthappa
- Department
of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, United States
| | - Dafni Moatsou
- Department
of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura,
Nishikyo-ku, Kyoto 615-8510, Japan
| | - Rachel K. O’Reilly
- Department
of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Makoto Ouchi
- Department
of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura,
Nishikyo-ku, Kyoto 615-8510, Japan
| | - Mitsuo Sawamoto
- Department
of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura,
Nishikyo-ku, Kyoto 615-8510, Japan
| | - Timothy P. Lodge
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
- Department
of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, United States
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30
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Giliomee J, Pfukwa R, Gule NP, Klumperman B. Smart block copolymers of PVP and an alkylated PVP derivative: synthesis, characterization, thermoresponsive behaviour and self-assembly. Polym Chem 2016. [DOI: 10.1039/c5py01609f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Stimuli responsive block copolymers of biocompatible poly(3-ethyl-N-vinylpyrrolidone) and poly(N-vinylpyrrolidone), i.e. EPVP–PVP, were readily synthesized via RAFT-mediated polymerization.
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Affiliation(s)
- Johnel Giliomee
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Nonjabulo P. Gule
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
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31
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Reader PW, Pfukwa R, Jokonya S, Arnott GE, Klumperman B. Synthesis of α,ω-heterotelechelic PVP for bioconjugation, via a one-pot orthogonal end-group modification procedure. Polym Chem 2016. [DOI: 10.1039/c6py01296e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A simple one pot orthogonal procedure for synthesizing α-aldehyde, ω-thiol heterotelechelic poly(N-vinylpyrrolidone) (PVP) is introduced.
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Affiliation(s)
- Paul. W. Reader
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Simbarashe Jokonya
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Gareth E. Arnott
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
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Du Prez F, Hoogenboom R, Klumperman B, Meier M, Monteiro M, Müller A, Vancso J. Fifty years of polymer science. Eur Polym J 2015. [DOI: 10.1016/j.eurpolymj.2015.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Ilchev A, Pfukwa R, Hlalele L, Smit M, Klumperman B. Improved control through a semi-batch process in RAFT-mediated polymerization utilizing relatively poor leaving groups. Polym Chem 2015. [DOI: 10.1039/c5py01293g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The negative effect that a RAFT agent with a poor leaving group has on the evolution of molecular dispersity in a RAFT-mediated polymerization was shown to be mitigated by performing the polymerization in semi-batch mode.
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Affiliation(s)
- Alexander Ilchev
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Lebohang Hlalele
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Marica Smit
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602
- South Africa
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35
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van Wijk J, Salari JWO, Meuldijk J, Klumperman B. Determination of the shell growth direction during the formation of silica microcapsules by confocal fluorescence microscopy. J Mater Chem B 2015; 3:7745-7751. [DOI: 10.1039/c5tb01232e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel procedure was developed to determine the direction of silica growth during the formation of a silica shell around aqueous microdroplets in water-in-oil Pickering emulsions, and it was found that the shell grows from the inside to the outside.
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Affiliation(s)
- Judith van Wijk
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- 5600 MB Eindhoven
- The Netherlands
| | - Joris W. O. Salari
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- 5600 MB Eindhoven
- The Netherlands
| | - Jan Meuldijk
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- 5600 MB Eindhoven
- The Netherlands
| | - Bert Klumperman
- Stellenbosch University
- Dept. Chemistry and Polymer Science
- South Africa
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36
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Swanepoel A, du Preez I, Mahlangu T, Chetty A, Klumperman B. Development of bioconjugated dye-doped poly(styrene-co-maleimide) nanoparticles as a new bioprobe. J Mater Chem B 2015; 3:2635-2640. [DOI: 10.1039/c4tb01520g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fluorescent dye-doped poly(styrene-co-maleimide) nanoparticles were synthesised and functionalized with amine groups and avidin and the dye-loading was varied.
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Affiliation(s)
- A. Swanepoel
- Polymers and Composites
- Materials Science and Manufacturing
- Council for Scientific and Industrial Research
- Pretoria
- South Africa
| | - I. du Preez
- Polymers and Composites
- Materials Science and Manufacturing
- Council for Scientific and Industrial Research
- Pretoria
- South Africa
| | - T. Mahlangu
- Polymers and Composites
- Materials Science and Manufacturing
- Council for Scientific and Industrial Research
- Pretoria
- South Africa
| | - A. Chetty
- Polymers and Composites
- Materials Science and Manufacturing
- Council for Scientific and Industrial Research
- Pretoria
- South Africa
| | - B. Klumperman
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Stellenbosch
- South Africa
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37
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Salari JWO, Mutsaers G, Meuldijk J, Klumperman B. Deformation of the water/oil interface during the adsorption of sterically stabilized particles. Langmuir 2014; 30:7327-7333. [PMID: 24905556 DOI: 10.1021/la501334p] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The adsorption of sterically stabilized colloids at water/oil (w/o) interfaces is studied experimentally by the formation of Pickering emulsions. Specifically, the effect of the steric stabilizer with respect to the rate of particle adsorption is investigated. Uniform, micrometer-sized poly(methyl methacrylate) (pMMA) particles, which are sterically stabilized with poly(isobutylene) (pIB), are used. The pIB concentration on the particle surface (ΓPIB) is controlled during the synthesis by adjusting the pIB/monomer ratio. Pickering emulsions are formed directly by the addition of water to the nonaqueous pMMA dispersions and subsequent emulsification. A strong dependence of the rate of particle adsorption on ΓPIB is found. The rate constant k for particle adsorption decays exponentially with ΓPIB, which suggest the use of a Boltzmann factor to model the experimentally found rate constants. The experimental results can be explained when the activation barrier for particle adsorption EA is of the same order as the average kinetic energy EK of a particle colliding with an emulsion droplet, which is equivalent to 10(5) kBT. Interestingly, this makes EA several orders of magnitude greater than the steric interaction with another particle. A possible mechanism that can lead to such a significant repulsive force is the inhibited drainage of solvent between the particle and o/w interface. Deformation of the o/w interface then occurs, when the solvent does not have time to drain, which results in a dramatic increase in the interfacial energy. This study identified the relevance of drainage in the formation of Pickering emulsions.
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Affiliation(s)
- Joris W O Salari
- Laboratory of Polymer Chemistry and ‡Laboratory of Chemical Reactor Engineering, University of Technology Eindhoven , P.O. Box 513, 5600 MB Eindhoven, The Netherlands
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Affiliation(s)
- Waled Hadasha
- Department of Chemistry and Polymer Science; Stellenbosch University; Private Bag X1 Matieland 7602 South Africa
| | - Bert Klumperman
- Department of Chemistry and Polymer Science; Stellenbosch University; Private Bag X1 Matieland 7602 South Africa
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van Wijk J, van Deventer N, Harmzen E, Meuldijk J, Klumperman B. Formation of hybrid poly(styrene-co-maleic anhydride)–silica microcapsules. J Mater Chem B 2014; 2:4826-4835. [DOI: 10.1039/c4tb00473f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A technique for the micro-encapsulation of a contamination-free aqueous droplet is presented.
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Affiliation(s)
- Judith van Wijk
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- 5600 MB Eindhoven, The Netherlands
| | - Nedine van Deventer
- Stellenbosch University
- Dept Chemistry and Polymer Science
- Matieland 7602, South Africa
| | - Elrika Harmzen
- Stellenbosch University
- Dept Chemistry and Polymer Science
- Matieland 7602, South Africa
| | - Jan Meuldijk
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- 5600 MB Eindhoven, The Netherlands
| | - Bert Klumperman
- Stellenbosch University
- Dept Chemistry and Polymer Science
- Matieland 7602, South Africa
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Abstract
Lactobacillus plantarum strain 423 was encapsulated in hollow poly(organosiloxane) microcapsules by templating water-in-oil Pickering emulsion droplets via the interfacial reaction of alkylchlorosilanes.
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Affiliation(s)
- Judith van Wijk
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- , The Netherlands
| | - Tiaan Heunis
- Department of Microbiology
- Stellenbosch University
- 7602 Matieland, South Africa
| | - Elrika Harmzen
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602, South Africa
| | - Leon M. T. Dicks
- Department of Microbiology
- Stellenbosch University
- 7602 Matieland, South Africa
| | - Jan Meuldijk
- Eindhoven University of Technology
- Department of Chemical Engineering and Chemistry
- , The Netherlands
| | - Bert Klumperman
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602, South Africa
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41
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Cronje L, Klumperman B. Modified electrospun polymer nanofibers as affinity membranes: The effect of pre-spinning modification versus post-spinning modification. Eur Polym J 2013. [DOI: 10.1016/j.eurpolymj.2013.08.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Pfukwa R, Kouwer PHJ, Rowan AE, Klumperman B. Templated Hierarchical Self-Assembly of Poly(p-aryltriazole) Foldamers. Angew Chem Int Ed Engl 2013; 52:11040-4. [DOI: 10.1002/anie.201303135] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 07/23/2013] [Indexed: 11/06/2022]
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Shi Y, van den Dungen ETA, Klumperman B, van Nostrum CF, Hennink WE. Reversible Addition-Fragmentation Chain Transfer Synthesis of a Micelle-Forming, Structure Reversible Thermosensitive Diblock Copolymer Based on the N-(2-Hydroxy propyl) Methacrylamide Backbone. ACS Macro Lett 2013; 2:403-408. [PMID: 35581846 DOI: 10.1021/mz300662b] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A diblock copolymer composed of N-(2-hydroxy propyl) methacrylamide (HPMAm) as hydrophilic block and N-(2-hydroxy propyl) methacrylamide dilactate (HPMAm-Lac2) as thermosensitive block was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. To this end, HPMAm was first polymerized with 4-cyano-4-[(dodecylsulfanylthiocarbonyl)-sulfanyl]pentanoic acid as the chain transfer agent and azobisisobutyronitrile (AIBN) as the initiator. The polymerization showed a linear increase in Mn as a function of monomer conversion. The living p(HPMAm) chain (7 kDa) was subsequently extended with HPMAm-Lac2 yielding a diblock copolymer (total Mn of 22 kDa). The copolymer showed reversible thermosensitivity in aqueous solution and self-assembled into micelles with a size of 58 nm (PDI 0.13) above its critical micelle temperature (CMT, 2.1 °C) and concentration (CMC, 0.044 mg/mL) and was soluble below the CMT. Paclitaxel, a hydrophobic chemotherapeutic drug, was encapsulated in the micelles with a loading capacity of 16.1 ± 1.2%. Hydrolysis of the dilactate side groups of the p(HPMAm-Lac2) block converted the copolymer to the fully hydrophilic p(HPMAm) homopolymer, resulting in dissociation of the micelles. In conclusion, the livingness and versatility of RAFT polymerization provide possibilities to synthesize block copolymers with HPMAm and derivatives thereof.
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Affiliation(s)
- Yang Shi
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, P.O. Box 80082, 3508 TB, Utrecht,
The Netherlands
| | - Eric T. A. van den Dungen
- Department
of Chemistry and
Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - Bert Klumperman
- Department
of Chemistry and
Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - Cornelus F. van Nostrum
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, P.O. Box 80082, 3508 TB, Utrecht,
The Netherlands
| | - Wim E. Hennink
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, P.O. Box 80082, 3508 TB, Utrecht,
The Netherlands
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Gule NP, de Kwaadsteniet M, Cloete TE, Klumperman B. Furanone-containing poly(vinyl alcohol) nanofibers for cell-adhesion inhibition. Water Res 2013; 47:1049-1059. [PMID: 23261340 DOI: 10.1016/j.watres.2012.11.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 11/03/2012] [Accepted: 11/07/2012] [Indexed: 06/01/2023]
Abstract
The 3(2H) furanone derivative 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) was investigated for its antimicrobial and cell-adhesion inhibition properties against Klebsiella pneumoniae Xen 39, Staphylococcus aureus Xen 36, Escherichia coli Xen 14, Pseudomonas aeruginosa Xen 5 and Salmonella typhimurium Xen 26. Nanofibers electrospun from solution blends of DMHF and poly(vinyl alcohol) (PVA) were tested for their ability to inhibit surface-attachment of bacteria. Antimicrobial and adhesion inhibition activity was determined via the plate counting technique. To quantify viable but non-culturable cells and to validate the plate counting results, bioluminescence and fluorescence studies were carried out. Nanofiber production was upscaled using the bubble electrospinning technique. To ascertain that no DMHF leached into filtered water, samples of water filtered through the nanofibrous mats were analyzed using gas chromatography coupled with mass spectrometry (GC-MS). Scanning electron microscopy (SEM) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) were used to characterize the electrospun nanofibers.
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Affiliation(s)
- Nonjabulo P Gule
- Division of Polymer Science, University of Stellenbosch, Stellenbosch, South Africa
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Cronje L, Warren R, Klumperman B. pH-dependent adhesion of mycobacteria to surface-modified polymer nanofibers. J Mater Chem B 2013; 1:6608-6618. [DOI: 10.1039/c3tb21393e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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49
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van Wijk J, Salari JWO, Zaquen N, Meuldijk J, Klumperman B. Poly(methyl methacrylate)–silica microcapsules synthesized by templating Pickering emulsion droplets. J Mater Chem B 2013; 1:2394-2406. [DOI: 10.1039/c3tb20175a] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Bailly N, Thomas M, Klumperman B. Poly(N-vinylpyrrolidone)-block-poly(vinyl acetate) as a Drug Delivery Vehicle for Hydrophobic Drugs. Biomacromolecules 2012; 13:4109-17. [DOI: 10.1021/bm301410d] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nathalie Bailly
- Department of Chemistry and
Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Mark Thomas
- Department of Physiological
Sciences, Stellenbosch University, Private
Bag X1, Matieland 7602, South Africa
| | - Bert Klumperman
- Department of Chemistry and
Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
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