A hydrophile is a molecule or other molecular entity that is attracted to water molecules and tends to be dissolved by water. As a result, pegylated liposomes have to be further stabilized, such as by using a large amount cholesterol. The wetting properties can be switched between superhydrophobic and superhydrophilic by simply changing the plasma chemistry. Citeseerx document details isaac councill, lee giles, pradeep teregowda. Because the natural world is full of hydrophobic and hydrophilic surfaces, the basics of the phenomenon have been known by scientists for at least two centuries. Pcbmodified liposomes without cholesterol exhibited good retention of hydrophilic drug and long blood circulating characteristics in vivo. Leveraging this optimized polymer structure containing a balance of cationic and hydrophobic content in the sirnacondensing block, we explored the effect of varying the. Eisenthal department of chemistry, columbia university, new york, new york 10027 usa abstract second harmonic generation shg was used to study both the adsorption of malachite green mg, a positively. The thiophene monomer was used as organic precursor. Since peg polyethylene glycol is a flexible, hydrophilic polymer with low toxicity, it can be considered as proper substance to create polymer matrix in which liposomes can be incorporated and topically applied.
Liposomes can be coated by hydrophilic molecules such as polysaccharides, which disguise the vesicle surface by creating a threedimensional. Beyond the use of zwitterionic materials as nonfouling bioinert materials, li et al. In addition to peg, various polymers including poloxamers, poloxamines, dextran, sialic acid derivatives, polyacrylic and polyvinyl polymers, and polyglycerols have also been attempted for use as liposome stabilizers with mixed outcomes. Superhydrophobic andor superhydrophilic surfaces made by. Reduction in marking by opsonins leads to slower uptake of these lipo. Superhydrophilic zwitterionic polycarboxybetaine and. Effect of various nonionic surfactants incorporated in. For example, the lotus leaf is a wellknown example of a hydrophobic material, protecting the.
Synthesis and characterization of hydrophilic silicone. Various surfactantscontaining vesicles have been widely used as a carrier in drug delivery to enhance skin penetration of encapsulated therapeutic agents. Some examples are instant snow polymer, which instantly expands to 40 times its original volume when mixed with water, producing a snowlike material, and sodium polyacrylate, the superabsorbent polymer found in disposable baby diapers, also used in many disappearing water magic tricks. Oct 06, 2015 hydrophilic polymers can absorb water equivalent to hundreds of times their own weight. Interaction of liposomes on endothelial cells author. Anchoring property of a novel hydrophilic lipopolymer. Liposomes as carriers of hydrophilic small molecule drugs. Zwitterionic materials, in contrast, resolve peg limitations owing to their superhydrophilic nature. Liposomes can be used in the delivery of various cosmetic materials, vitamins, and minerals throughout the body, typically to the skin, for an array of advantages such as antioxidant benefits, conditioning, and antimicrobial purposes. This thesis examines functional hydrophilic polymers designed in linear and comb architectures and that carry functional moieties in the context of solution assembly and nonviral gene therapy. Di erent forces acting on and among lipid molecules in liposome membrane in. Since then, liposomes have made their way to the market. Zwitterionic polymers are characterized with equal anion and cation groups on the molecular chains, which make them highly hydrophilic and antifouling.
A liposomal formulation able to incorporate a high content. Some examples are instant snow polymer, which instantly expands to 40 times its original volume when mixed with water, producing a snowlike material, and sodium polyacrylate, the super absorbent polymer found in disposable baby diapers, also used in many disappearing water magic tricks. The pdmaemacobma segment was blocked with a superhydrophilic, zwitterionic phosphorylcholinebased polymer p 2methacryloyloxyethyl phosphorylcholine pmpc to form the np corona. The ratio of the hydrophilic part to the total mass of the copolymers f value is a determinant factor in the formation of different nano structures 68. Hydrophilization is a process used for hydrophobic drugs to increase their release rate from capsules, which is dependent on the rate of dissolution, by covering the surface of the drug particles with minute droplets of a hydrophilic polymer solution method.
A hydrophilic colloid, or hydrocolloid, is defined as a colloid system in which the colloid particles are hydrophilic polymers dispersed in water. Polyethylene glycol pegphospholipids in longcirculating liposomes cause nonspecific immune reactions. Liposomes modified with temperatureresponsive polymers are. For example, agar is a reversible hydrocolloid of seaweed extract. Liposomes are ubiquitous components of skin moisturizers and other personalcare products.
Advancement in the gene delivery system have resulted in clinical successes in gene therapy for patients with several genetic diseases, such as immunodeficiency diseases, xlinked adrenoleukodystrophy xald blindness, thalassemia, and many more. Surface functionalization of nanoparticles nps with stealth polymers e. In this work, we show that zwitterionic poly carboxybetaine pcb. As a result, pegylated liposomes have to be further stabilized, such as. Liposomes are closer mimics to eukaryotic cell membranes but are difficult to handle and use whereas polymersomes are tougher, malleable, stable vesicles. The task at hand was to develop an understanding of water structure in crosslinked, hydrophilic polymers and copolymers containing 2,3dihydroxypropyl methacrylate dhpmaand 2hydroxyethyl methacrylate hema. Due to the hydrophilic functional groups such as oh, cooh and so3h present in the molecular structure, zwitterionic polymers are capable of resisting nonspecific protein adsorption,bacterial. Solvents, mixtures, compounds, and particles are just some of the components of a chemists life. Polymersomebased drugdelivery strategies for cancer. The main component, psbma, is a highly hydrophilic zwitterionic polymer with a high potential for biomedical application. The silicon atoms can also be bonded to organic groups, such as methyl groups see table 1. Peg and pmox, the polymers that can initiate an abc response were the two most viscous polymers. Complex, lodi road, new delhi 110 003 received 6 april 2000.
Today, they are a very useful reproduction, reagent, and tool in various scientific disciplines, including mathematics and theoretical physics, biophysics, chemistry, colloid science, biochemistry, and biology. If the f value is higher than 50%, the formation of micelles is possible, and if. To further validate this new pcb chemistry, pcb liposomal doxorubicin without cholesterol was compared. Sterically stabilized liposomes can be formu lated by incorporating hydrophilic longchain polymers in the bilayer which can form a coat on the liposome surface and repel opsonin penetra tion and adsorption. A key factor in liposomes modified with temperaturedependent polymers is the temperature at which its solubility profile changes, known as the lower critical solution temperature lcst. Difference between hydrophilic and hydrophobic difference. Hydrophilic polymers contain polar or charged functional groups, rendering them soluble in water. The effect of polymer backbone chemistry on the induction. Liposomes and polymersomes present many different properties. We investigated a novel lipopolymer, by which a superhydrophilic polymer shp is conjugated to a nonphospholipid n12aminoethyln4hexadecyl2tetradecylsuccinamide hdas.
Sep 19, 2012 liposomes are ubiquitous components of skin moisturizers and other personalcare products. The liposomes, composed of naturally unsaturated and hydrogenated phosphatidylcholines, with significant phase transition temperature difference, were prepared and characterized. Effects of bilayer surface charge density on molecular adsorption and transport across liposome bilayers yan liu, elsa c. Specifically, polymers containing cations, zwitterions, and reactive groups are investigated as nonviral gene therapy reagents and at oilwater interfaces on droplets. The liposomes exhibited a high content of paclitaxel, which was incorporated within the segregated microdomains coexisting on phospholipid bilayer of. Synthesis and characterization of hydrophilic silicone copolymers. Recent trends of polymer mediated liposomal gene delivery. Nonionic polyethylene glycol peg as a stealth polymer destabilizes liposomes due to its amphiphilic property.
Superhydrophobic andor superhydrophilic surfaces made. Dual carriercargo hydrophobization and charge ratio. The size and electrophoretic mobility of zwitterionic liposomes was found to increase with the cholesterol composition. Effects of bilayer surface charge density on molecular. Hydrophilic polymers are those polymers which dissolve in, or are swollen by, water. By using a stencil mask to selectively modify areas on the surface with different chemicals, both superhydrophobic and hydrophilic areas can. They are special class of polyampholytes named polybetaines or polyzwitterions. Studies involving the observance of molecule behavior in any given state or environment may seem to be one of the most brainwhacking jobs for those with little background in chemistry and related sciences, but these are very helpful in coming up with the latest.
Many compounds of major technical and economic importance fall within this definition, including many polymers of. For example, the lotus leaf is a wellknown example of a hydrophobic material, protecting the waterdwelling plant from becoming waterlogged. Functional hydrophilic polymers for solution assembly and. Hydrocolloids can be either reversible or irreversible singlestate. In contrast, hydrophobes are not attracted to water and may seem to be repelled by it. Typically, polymersomes are prepared from amphiphilic, linear block copolymers.
Our findings suggest that that polymers that do not cause an abc effect such as, hpma or pvp, deserve further consideration as polymer coatings to improve the circulation of liposomes and other nanoparticles. Unlike amphiphilic peg, zwitterionic polymers are super hydrophilic, and insoluble in most organic solvents. Based on this evidence, numerous zwitterionic polymers have been widely synthesized as stealth candidates for drug delivery system 79,80. Within this section, most hydrophilic polymers are grouped by the chemistry of their structure. Jul 17, 2012 zwitterionic oligopeptide liposomes hhg2c 18. Nonetheless stability does not always rhyme with cell mimicry as fluidity is a key parameter of cell membranes.
The purpose of this study was to investigate the effect of nonionic surfactantscontaining liposome vesicles on the penetration of hydrophilic compounds through the porcine skin. Characterization and analytical applications of dye. May 08, 2009 the wetting properties can be switched between super hydrophobic and super hydrophilic by simply changing the plasma chemistry. The zwitterionic functionality presumably orients to the surface on contact with water 24 in a kind of amorphous selfassembly. The most common silicone and in largest volume produced is polydimethylsiloxane, pdms. Janez strancar november 18, 2010 abstract liposomes are small vesicles. If the f value is higher than 50%, the formation of micelles is possible, and if the value is 4050%, wormlike structures are. In nature hydrophilic products like protein, keratin or wool are responsible for water vapor permeability. Critical packing parameter cpp if cpp value is less than 0. Recent trends of polymer mediated liposomal gene delivery system. Unlike amphiphilic peg, zwitterionic polymers are superhydrophilic, and insoluble in most organic solvents.
Interactions between ionic centers of protein and zwitterionic network facilitated dynamic sequestering and. Hydrophilic polymeric nanoparticles as drug carriers. Check out these hydrophilic polymer materials below. Many compounds of major technical and economic importance fall within this definition, including many polymers of natural origin. By using a stencil mask to selectively modify areas on the surface with different chemicals, both super hydrophobic and hydrophilic areas can be created on a single surface. Jul 16, 20 because the natural world is full of hydrophobic and hydrophilic surfaces, the basics of the phenomenon have been known by scientists for at least two centuries. Such super hydrophilic character circumvents the hydrophobic character of peg mentioned above. In this study, the sio polymer coating film was prepared the containing tetraethyl orthosilane teos solution by the solgel method on soda lime glass. Dec 28, 20 in addition to peg, various polymers including poloxamers, poloxamines, dextran, sialic acid derivatives, polyacrylic and polyvinyl polymers, and polyglycerols have also been attempted for use as liposome stabilizers with mixed outcomes. Molecular structures of nonionic eg and zwitterionic cb headgroups. The easiest way to obtain water vapor permeability for a chemist should be the of use a hydrophilic polymer. Liposomes, sphereshaped vesicles consisting of one or more phospholipid bilayers, were first described in the mid60s. They can resist nonspecific protein adsorption, bacterial adhesion, and biofilm formation. Citeseerx surface modified liposomes by coating with.
The design of liposomes with a hydrophilicsteric barrier at their bilayer surface allows the modification of their pharmacokinetics and reduces the uptake by the res. Superhydrophilic zwitterionic polymers stabilize liposomes. Peg is amphiphilic with both hydrophilic and hydrophobic properties. Liposomes modified with temperatureresponsive polymers. Zwitterion comonomers enhance the surface hydrophilicity of dimethylsiloxane polymers, 25 as illustrated by a reduced water contact angle. Polyzwitterions are a class of polymers consisting of zwitterionic moieties as monomers. Thats because instead of dissolving in water as other types of powders do, ultraabsorbent polymers create a physical not a chemical bond with the water. Hydrophilic polymers can absorb water equivalent to hundreds of times their own weight. For example, acrylics include acrylic acid, acrylamide, and maleic anhydride polymers and copolymers. Therefore, they have great potential to be applied in a wide range. Zwitterionic liposomes were used as a coating to cap the surface of drug reservoir polydopamine. The effect of polymer backbone chemistry on the induction of.
The interaction of indolicidin, a mer cationic amp, with dyeencapsulated liposomes that were made of different lipid and cholesterol composition was investigated by dls, fluorescence and capillary electrophoresis ce. The design of liposomes with a hydrophilic steric barrier at their bilayer surface allows the modification of their pharmacokinetics and reduces the uptake by the res. Sterically stabilized liposomes can be formu lated by incorporating hydrophilic longchain polymers in the bilayer which can form a coat on the liposome surface and repel opsonin penetra. Modified liposomes prepared from receptorlike molecules open up fresh opportunities for therapeutic and. A liposome formulation for paclitaxel was developed in this study. After then, the plasma polymer coating was deposited on sio polymer coated glass by plasma enhanced chemical vapor deposition pecvd method at room temperature during 15 seconds.
Hydrophilic polyester watersoluble, waterdispersible, waterswellable polymers compatibilization of polymer alloys amine end groups are much more reactive than alcohol end groups improved hydrolysis resistance flexibility from polyether backbone. The liposomes may attach and fuse to the cellular membranes, releasing their contents into the target cells. The number of carbon groups n between the positive quaternary amine group and the negative carboxylate group of each pcb unit can be varied. A liposomal formulation able to incorporate a high content of. The process is accomplished by vigorous mixing of the hydrophobic drug with the aqueous solution of the hydrophilic polymer solution. Among various delivery systems, liposomal mediated gene delivery route is offering great promises for gene therapy. Anchoring property of a novel hydrophilic lipopolymer, hdas. There are a lot of existing polymeric materials which are hydrophilic, e. Polyampholytes specifically possess the charged groups on different monomer units, while polymers possess anionic and cationic groups on the same monomer unit are. Hydrophilic polymeric nanoparticles as drug carriers p k ghosht department of biotechnology, ministry of science and technology, block 2, c. Such superhydrophilic character circumvents the hydrophobic character of peg mentioned above. Stealth coating of nanoparticles in drugdelivery systems.