Ammonium Propane Sulfonate Research Articles

Synthesis and characterization of novel drug delivery nanoparticles based on polyzwitterionic copolymers

Copolymer (vinyl acetate (VA)-co-3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate (DMAPS)) nanoparticles have been synthesized by radical copolymerization in water. It was established that the variation of the initial monomer feed (DMAPS concentration was 10mol% (copolymer 1) and 90mol% (copolymer 2)) changes the copolymerization type, nanoparticles morphology, self-organization and size distribution. The shape, average diameter, size distribution and zeta potential of the copolymer nanoparticles are determined by atomic force microscopy (AFM), dynamic light scattering and zeta potential data, respectively. While the copolymer 1 nanoparticles are solid with spherical shape, average diameter 276nm and zeta potential −25.2mV, the copolymer 2 nanoparticles have bean-like shapes with an average diameter 49.3nm and zeta potential −4.4mV and contain many domains with different density. For the first time the AFM images of the copolymer 2 nanoparticles presented the unique self-organization of the dipole–dipole clusters of DMAPS units. The results indicated that the obtained copolymer nanoparticles with specific structure could be used as drug delivery systems.

Polyurethanes containing zwitterionic sulfobetaines and their molecular chain rearrangement in water

Novel polyurethanes with zwitterionic sulfobetaines, termed PUR-APS, were designed and synthesized by chain-extension of biodegradable poly(ε-caprolactone) containing N,N'-bis (2-hydroxyethyl) methylamine ammonium propane sulfonate (PCL-APS) with hexamethylene diisocyanate (HDI). The bulk properties of polymers were characterized by nuclear magnetic resonance spectrum (NMR), Fourier transform infrared spectroscopy (FTIR), gel permeation chromatograph (GPC), and differential scanning calorimetry (DSC). Results showed that the polymers were successfully synthesized. Water contact angles (WCAs) and X-ray photoelectron spectroscopy (XPS) revealed that molecular chains of the polymers rearranged after soaking in water. The amount of protein adsorption, determined by bicinchoninic acid (BCA) assay, was less than 300 ng/cm(2) and decreased after hydration. The blood compatibility of the polymers was evaluated by the degree of hemolytic and activated partial thromboplastic time (APTT) and prothrombin time (PT). Results indicated that PUR-APS polymers had good blood compatibility. Therefore, polyurethanes containing sulfobetaines have a great potential for biomedical application.

Characteristics of zwitterionic sulfobetaine acrylamide polymer and the hydrogels prepared by free-radical polymerization and effects of physical and chemical crosslinks on the UCST

A zwitterionic sulfobetaine polymer, poly(N,N-dimethyl(acrylamidopropyl) ammonium propane sulfonate) (poly(DMAAPS)), and the hydrogels of this polymer were synthesized by free-radical polymerization in an aqueous redox system using a wide range of monomer concentrations (Cm). The resulting polymers were characterized in terms of polymer yield, intrinsic viscosity, molecular weight, gel fraction, and thermoresponsive phase-transition behavior. Parameters in the Mark–Houwink–Sakurada equation, including the molecular-weight exponent α, were determined for poly(DMAAPS) in 0.1M NaCl aqueous solution. The physical state and transparency of the poly(DMAAPS) samples were strongly dependent on Cm and temperature. At higher values of Cm (i.e. above a critical molecular weight), poly(DMAAPS) became a gel comprising a physically crosslinked network consisting of entangled polymer chains and interchain associations of the zwitterionic groups. The poly(DMAAPS) solutions or gels exhibited a thermoresponsive phase transition with an upper critical solution temperature (UCST). The gels obtained were completely soluble in aqueous NaCl solution at ambient temperature as well as in water at temperatures above UCST. The effects of molecular weight, chemical crosslink density and copolymerization on the UCST were also elucidated.

Functional polymer brushes via surface-initiated atom transfer radical graft polymerization for combating marine biofouling

Dense and uniform polymer brush coatings were developed to combat marine biofouling. Nonionic hydrophilic, nonionic hydrophobic, cationic, anionic and zwitterionic polymer brush coatings were synthesized via surface-initiated atom transfer radical polymerization (SI-ATRP) of 2-hydroxyethyl methacrylate, 2,3,4,5,6-pentafluorostyrene, 2-(methacryloyloxy)ethyl trimethylammonium chloride, 4-styrenesulfonic acid sodium and N,N′-dimethyl-(methylmethacryloyl ethyl) ammonium propanesulfonate, respectively. The functionalized surfaces had different efficacies in preventing adsorption of bovine serum albumin (BSA), adhesion of the Gram-negative bacterium Pseudomonas sp. NCIMB 2021 and the Gram-positive Staphylococcus aureus, and settlement of cyprids of the barnacle Amphibalanus amphitrite (=Balanus amphitrite). The nonionic hydrophilic, anionic and zwitterionic polymer brushes resisted BSA adsorption during a 2 h exposure period. The nonionic hydrophilic, cationic and zwitterionic brushes exhibited resistance to bacterial fouling (24 h exposure) and cyprid settlement (24 and 48 h incubation). The hydrophobic brushes moderately reduced protein adsorption, and bacteria and cyprid settlement. The anionic brushes were least effective in preventing attachment of bacteria and barnacle cyprids. Thus, the best approach to combat biofouling involves a combination of nonionic hydrophilic and zwitterionic polymer brush coatings on material surfaces.

Copolymer nanoparticles composed of sulfobetaine and poly(ε‐caprolactone) as novel anticancer drug carriers

Novel ABA type amphiphilic copolymers (PCL-APS-PCL) consisting of polycaprolactone (PCL) (A) as hydrophobic block and N,N'-bis (2-hydroxyethyl) methylamine ammonium propane sulfonate (APS) (B) as hydrophilic segment, self-assembled into nanoparticles (NPs) with solvent evaporation method. The sizes and size distributions of NPs were characterized by dynamic light scattering. The morphology of NPs was observed by scanning electron microscopy (SEM). The critical micelle concentration (CMC) was determined by fluorescent probe. The drug loading content (DLC) and the drug release amount were characterized by UV-visible spectrophotometer. The cytotoxicity of the NPs was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylte-trazoliumbromide (MTT) assay. It was found that the NPs were spherical in shape with sizes around 100 nm. The CMCs of the copolymers were quite low (×10(-4) mg/mL). The DLC decreased with lengthening of hydrophobic PCL block. In vitro drug release experiment demonstrated that the release rate of paclitaxel sped with the decrease of PCL length. MTT results showed that NPs were nontoxic to osteoblast and human epithelial carcinoma (hela) cells. After drug loading, NPs could restrain the growth of hela or even kill hela cells. Therefore, these preliminary studies suggest that the novel PCL-APS-PCL NPs have a great potential application as anticancer drug-delivery carriers.

Biocompatible Zwitterionic Sulfobetaine Copolymer‐Coated Mesoporous Silica Nanoparticles for Temperature‐Responsive Drug Release

A novel nanocontainer, which could regulate the release of payloads, has been successfully fabricated by attaching zwitterionic sulfobetaine copolymer onto the mesoporous silica nanoparticles (MSNs). RAFT polymerization is employed to prepare the hybrid poly(2-(dimethylamino)ethyl methacrylate)-coated MSNs (MSN-PDMAEMA). Subsequently, the tertiary amine groups in PDMAEMA are quaternized with 1,3-propanesultone to get poly(DMAEMA-co-3-dimethyl(methacryloyloxyethyl)ammonium propanesulfonate)-coated MSNs [MSN-Poly(DMAEMA-co-DMAPS)]. The zwitterionic PDMAPS component endows the nanocarrier with biocompatibility, and the PDMAEMA component makes the copolymer shell temperature-responsive. Controlled release of loaded rhodamine B has been achieved in the saline solutions.

Preparation and evaluation of well-defined hemocompatible layered double hydroxide-poly(sulfobetaine) nanohybrids

The ability to manipulate and control the surface properties of layered double hydroxide (LDH) nanoparticles is of crucial importance in the designing of LDH-based carriers of therapeutic agents. In this work, surface-initiated atom transfer radical polymerization (ATRP) of zwitterionic 3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) is first employed to tailor the functionality of LDH surfaces in a well-controlled manner and produce a series of well-defined hemocompatible hybrids (termed as LDHPS). The blood compatibilities of the modified LDH nanoparticles were investigated using coagulation tests, complement activation, platelet activation, hemolysis assay, morphological changes of red blood cells, and cytotoxicity assay. The results confirmed that the P(DMAPS) grafting can substantially enhance the hemocompatibility of the LDH particles, and the LDHPS hybrids can be used as biomaterials without causing any hemolysis. With the versatility of surface-initiated ATRP and the excellent hemocompatibility of zwitterionic polymer chains, the LDH nanoparticles with desirable blood properties can be readily tailored to cater to various biomedical applications.

Novel composite nanofiltration membranes containing zwitterions with high permeate flux and improved anti-fouling performance

This article provides a novel method for introducing zwitterionic polymers into nanofiltration membranes, with the aim of achieving high water flux and good anti-fouling performance. Terpolymers P(DMC-HEA-DMAPS) (PDHD) composed of 2-methacryloyloxy ethyl trimethylammonium chloride (DMC), 2-hydroxyethyl acrylate (HEA) and 3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) were synthesized via aqueous phase free-radical copolymerization. Composite nanofiltration membranes (CNFMs) were prepared with PDHD and glutaraldehyde (GA) via the combination of surface coating and chemical cross-linking methods. Chemical structures and compositions of PDHDs and CNFMs were characterized by (attenuated total reflectance) Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy and atomic force microscopy. The water permeability of CNFMs was examined with nanofiltration test and dynamic water contact angle measurement. Optimum nanofiltration performance was obtained for CNFM3 with 4.35 mol% DMAPS, e.g. R MgCl 2 = 96 .5 % , J MgCl 2 = 47 .8 L m − 2 h − 1 (testing with 1 g L −1 aqueous MgCl 2 solution at 25 °C and 0.6 MPa). Moreover, the extent of fouling for CNFM3 was significantly reduced and most of the fouling was reversible during the MgCl 2 and protein filtration test. Therefore, the water permeability and anti-fouling property of CNFMs were significantly improved with introducing zwitterionic groups into the membranes.

The Role of Surfactant Headgroup, Chain Length, and Cavitation Microstreaming on the Growth of Bubbles by Rectified Diffusion

The role of a surfactant on the rate of bubble growth via rectified diffusion during acoustic cavitation has been investigated. The charge of the headgroup of ionic surfactants did not affect the bubble growth rate at low surface loadings. However, at higher surface loading, the growth rate was significantly dependent upon the type and charge of the headgroup. Dodecyl trimethyl ammonium chloride (DTAC) caused a greater increase in growth rate than sodium dodecyl sulfate (SDS) or dodecyl dimethyl ammonium propane sulfonate (DDAPS). With charge suppressed by the addition of salt, DDAPS showed the highest growth rate. Particle-image velocimetry (PIV) has been used to characterize the microstreaming around a bubble in aqueous solutions of these surfactants. Results indicate an enhancement of microstreaming velocities in the vicinity of the bubble when surfactant of any form is present in the solution, with the greatest enhancement for the surfactant with the most bulky headgroup. A clear difference could also...

Improvement of Hemocompatibility of Polycaprolactone Film Surfaces with Zwitterionic Polymer Brushes

Polycaprolactone (PCL) has been widely adopted as a scaffold biomaterial, but further improvement of the hemocompatibility of a PCL film surface is still needed for wide biomedical applications. In this work, the PCL film surface was functionalized with zwitterionic poly(3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate) (P(DMAPS)) brushes via surface-initiated atom transfer radical polymerization (ATRP) for enhancing hemocompatibility. Kinetics study revealed an approximately linear increase in graft yield of the functional P(DMAPS) brushes with polymerization time. The blood compatibilities of the modified PCL film surfaces were studied by platelet adhesion tests of platelet-rich plasma and human whole blood, hemolysis assay, and plasma recalcification time (PRT) assay. The improvement of hemocompatibility is dependent on the coverage of the grafted P(DMAPS) brushes on the PCL film. Lower or no platelet and blood cell adhesion was observed on the P(DMAPS)-grafted film surfaces. The P(DMAPS) grafting can further decrease hemolysis and enhance the PRT of the PCL surface. With the versatility of surface-initiated ATRP and the excellent hemocompatibility of zwitterionic polymer brushes, PCL films with desirable blood properties can be readily tailored to cater to various biomedical applications.

Grafting Sulfoammonium Zwitterionic Brushes onto Polycarbonateurethane Surface to Improve Hemocompatibility

Poly(3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate) (poly(DMAPS)) zwitterionic brushes were grafted onto the polycarbonateurethane (PCU) surface to improve its hydrophilicity and hemocompatibility by Ultraviolet (UV) polymerization. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle were used to characterize the chemical and physical properties of the modified PCU surface. DMAPS-grafted PCU films showed significantly high hydrophilicity owing to the high hydrophilic poly(DMAPS) zwitterionic brushes. The cytotoxicity tests revealed the sulfoammonium zwitterionic brushes modified PCU film had good cytocompatibility. In addition, the hemocompatibility of the modified PCU films was evaluated by hemolytic tests and platelet adhesion tests. The PCU films modified with zwitterionic brushes had a lower hemolytic index, showed effective resistance to platelet adhesion. Due to the fact that sulfoammonium zwitterionic brushes can improve the hemocompatibility of the PCU surface, this gives rise to its potential application as blood-contacting materials or devices.

Thermosensitive properties of semi-IPN gel composed of amphiphilic gel and zwitterionic thermosensitive polymer in buffer solutions containing high concentration salt

In this study, a semi-interpenetrating polymer network (semi-IPN) gel, which consists of an amphiphilic N,N-dimethylacrylamide- co- N-isopropylacrylamide (DMAA- co-NIPAM) gel and an interpenetrating zwitterionic thermosensitive poly( N-isopropylacrylamide- co- N,N-dimethyl(acrylamidopropyl)ammonium propane sulfonate) (poly(NIPAM- co-DMAAPS)) was prepared. The thermosensitive behavior of the semi-IPN gel was investigated in a buffer solution composed of a relatively high concentration of sodium chloride and sodium citrate as salts, and sodium dodecyl sulfate as a surfactant, which are generally used as a buffer solution in biochips. At low temperatures, the semi-IPN gel in the buffer solution was absolutely transparent; however, when the gel was heated, the gel became milky white or opaque without a large change in the gel size. The network of the transparent gel is homogeneous, whereas that of the opaque gel consists of coarse and dense parts. Such a structural change in the gel network was confirmed by the temperature dependence of the permeability of the buffer solution through the semi-IPN gel membrane. The permeability increased drastically when the gel became opaque because of heating.

Enhancing blood compatibility of biodegradable polymers by introducing sulfobetaine

Novel biodegradable polycaprolactone containing N,N'-bis (2-hydroxyethyl) methylamine ammonium propane sulfonate (PCL-APS) was synthesized by ring-opening polymerization. The resulting polymers were characterized by nuclear magnetic resonance spectrum (NMR), Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatograph (GPC), differential scanning calorimetry (DSC), and water contact angle (WCA). These measurements showed that the APS unit was introduced into polymers. The hydrolysis of PCL-APS was evaluated by soaking the polymer membranes in a pH = 3.20 acid solution. The rate of weight loss was increased with the content of APS increasing in polymer. The compatibility of polymers were evaluated by platelet adhesion, hemolytic test, and activated partial thromboplastic time (APTT) and prothrombin time (PT) experiments. Results showed that adhered platelets deceased after introducing sulfobetaine as compared to the control PCL, little hemolysis took place on PCL-APS, and APTT of PCL-APS polymers was prolonged than that of control PCL. Therefore, polycaprolactone containing sulfobetaine is a promising biodegradable polymer with good blood compatibility.

Controllable disintegration of temperature-responsive self-assembled multilayer film based on polybetaine

A layer-by-layer (LbL) self-assembly technique was used to construct temperature-responsive multilayer films of polybetaine poly-3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate (PDMAPS) and poly(acrylic acid) (PAA). The assembly and disintegration behaviors of PDMAPS/PAA multilayer films were investigated by quartz crystal microbalance (QCM) and atomic force microscopy (AFM). The results indicated that the assembly behaviors of PDMAPS/PAA multilayer films could be well regulated by the pH and temperature of dipping solutions. The disintegration of PDMAPS/PAA multilayer films could be well controlled by varying the disintegration temperature ( T d) and the pH of buffer solution. The critical disintegration temperature ( T cd) decreased with increasing pH of buffer solution used. The ionization of carboxylic acid groups (COOH) of PAA and the breakage of intra-chain associations of PDMAPS in multilayer films are two main reasons for the film disintegration. Based on the controllable disintegration of the PDMAPS/PAA multilayer, free-standing multilayer films were successfully prepared by LbL self-assembly of poly(4-vinylpyridiniomethanecarboxylate) (PVPMC) and PAA using PDMAPS/PAA as a sacrificial sublayer.

Functional poly(vinylidene fluoride) copolymer membranes via surface-initiated thiol–ene click reactions

Thermally induced graft copolymerization of allyl methacrylate (AMA) from ozone-preactivated poly(vinylidene fluoride) (PVDF) chains was first carried out in N-methyl-2-pyrrolidone (NMP) solution to produce the PVDF-g-PAMA copolymers. The PVDF-g-PAMA copolymers were cast, by phase inversion in an aqueous medium, into microporous membranes with enriched allyl groups on the membrane and pore surfaces. The pendant allyl groups in the PAMA side chains allowed the thiol–ene click grafting of thiol-functionalized moieties on the membrane surface. Thermally initiated thiol–ene click reaction with 3-mercaptopropionic acid (MPA) produced the PVDF-g-P[AMA-comb-MPA] membrane which exhibited a pH-responsive permeation behavior, with the most drastic change in permeation rate of the aqueous media being observed between pH 2 and 4. The PVDF-g-P[AMA-comb-DMAPS] membrane was synthesized via UV-initiated thiol–ene click reaction of 1,6-hexanedithiol (HDT) with the PVDF-g-PAMA membranes, using 2,2-dimethoxy-2-phenylacetophenone (DMPA) as the photoinitiator, followed by thiol-Michael addition reaction of the zwitterionic molecules, N,N′-dimethyl-(methylmethacryloyl ethyl) ammonium propanesulfonate (DMAPS). A significant reduction in microbial adhesion was observed on the PVDF-g-P[AMA-comb-DMAPS] membrane in a flow chamber, in comparison to the pristine hydrophobic PVDF membrane.

Microwave-assisted nitroxide-mediated polymerization for water-soluble homopolymers and block copolymers synthesis in homogeneous aqueous solution

We performed a critical reinvestigation of microwave enhancement of nitroxide-mediated polymerization (NMP) of ac- rylamide (AM) in aqueous media in the dynamic (DYN) mode with a combination of a conventional hydrosoluble radical initia- tor and a b-phosphonylated nitroxide (SG1). Based on the results of our previous work, a complementary series of poly- merization reactions was carried out between 130 and 160 ! C using only the DYN mode to ascertain the existence of a micro- wave effect. The polymer conversion (p), molar masses, polydis- persity index, and viscosity of each sample were measured. The temperature was monitored inside and outside of the vessel using an optical fiber sensor and an IR sensor, respectively. Microwave enhancement of polymerization, temperature control and viscosity of the reaction media were closely related. We also furthered the field of hydrophilic AB diblock copolymer synthesis using a tertiary SG1-based macroalkoxyamine and directly synthesized both poly(acrylamide-b-sodium 2-acryla- mido-2-methylpropanesulfonate), a neutral-b-anionic diblock copolymer, and poly(acrylamide-b-3-dimethyl(methacrylamido- propyl)ammonium propanesulfonate), a neutral-b-zwitterionic diblock copolymer, in homogeneous aqueous media. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 5775-5782, 2010

Influence of salt concentration on swelling states of poly(sulfobetaine) brush at aqueous solution interface

Swelling states of poly(3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate) (DMAPS) brush in aqueous solutions with different salt concentrations were investigated by atomic force microscopy (AFM) and neutron reflectivity measurement. The thickness of swollen poly(DMAPS) brush evaluated by AFM was increased from 212 nm up to 352 nm with an increase in salt concentration from 0 to 0.5 M. Poly(DMAPS) brush chains formed shrunk structure in a pure water due to the attractive electrostatic inter- and intra-chain interaction of sulfobetaine groups, while the brush chains in NaCl aqueous solution were stretched up because the hydrated salt ions screened the attractive interaction.

Chaperone-Like Effect of Polyzwitterions on the Interaction of C1q with IgG

The amphiphilic polyzwitterion (PZ) poly(ethylene oxide-b-N,N-dimethyl(methacryloyloxyethyl)ammonium propanesulfonate), zwitterionic surfactant (ZS) n-dodecyl-N,N-dimethyl-3-ammonium-1-propanesulfonate, and zwitterionic monomer (ZM) N,N-dimethyl(methacryloyloxyethyl)ammonium propanesulfonate were analyzed for their suggested chaperone-like effect on the interaction of C1q and IgG. Our results proved that the PZ retarded the C1q interaction with IgG, demonstrating a specific protein-folding helper effect. The ZS enhanced this interaction, when the ZS concentration was lower than the critical micelle concentration (CMC), and retarded it, when the ZS concentration was above the CMC. The ZM, with no self-assembling ability, did not influence this interaction. These results support the hypothesis of a hydrophobic interaction between Pts and hydrophobic domains of partly denatured protein molecules. The amphiphilic self-assemblies, formed by polyzwitterionic macromolecules or zwitterionic surfactants, have the ability to transform the hydrophobic domains of the protein molecules into hydrophilic ones, covering them with their hydrophilic parts.

Synthesis and Characterization of Zwitterionic Co-polymers as Matrices for Sustained Metoprolol Tartrate Delivery

Very stable co-polymer (vinyl acetate (VA)-co-3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) (p(VA-co-DMAPS)) latexes with different compositions have been synthesized by emulsifier-free emulsion co-polymerization. The dry p(VA-co-DMAPS)s have been used in the preparation of drug tablets for sustained Metoprolol tartrate release. It has been shown that the tablet swelling depends on the mol fraction of DMAPS monomer units (m DMAPS), pH and ionic strength (I). An original explanation, based on the swelling behavior of p(VA-co-DMAPS), has been proposed for the "overshooting" phenomenon observed. It assumes the formation of hydrophilic domains with a higher m DMAPS in the co-polymer tablets. The formation of dipole–dipole clusters between the DMAPS units at different m DMAPS and I are the main cause for the established differences in both the swelling kinetics of the p(VA-co-DMAPS) matrices and Metoprolol tartrate release. The obtained results show that for p(VA-co-DMAPS) matrices-based tablets controlled sustained Metoprolol tartrate release can be realized just by varying two parameters, co-polymer composition and I.

Biocompatible zwitterionic copolymer networks with controllable swelling and mechanical characteristics of their hydrogels

The equilibrium swelling ratio in both water and physiological solution of the biocompatible copolymer networks of 3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate (DMAPS) and N-vinyl-2-pyrrolidone (NVP) is determined as a function of copolymer composition. It is established that equilibrium swelling ratio of the polymer networks in physiological solution increase with raise of zwitterionic monomer unit fraction. A sharp decrease of this ratio in water with increase of zwitterionic monomer unit fraction is related to the formation of thermolabile physical junctions produced by dipole-dipole interactions between the zwitterionic side groups. The same fact affects considerably the storage and loss moduli of the copolymer hydrogels as well as the morphology of the dried networks. Scanning electron microscopy images provided evidence of the occurrence of a lamellar structure forming the morphology of the polymers. This was corroborated by differential scanning calorimetry experiments. In this way a possibility for effective control on swelling ratio in different solutions and the mechanical properties of these novel biocompatible networks are established.