摘要:
In various embodiments, the present invention provides a strong, synthetic elastomer materials (and related methods for making same) with mechanical properties that are controlled by the stereochemically-defined double bonds within their backbone, yet have physical properties that are derived from monomer selection and defined, modifiable, chain end groups. The use of the organocatalyzed, stereospecific addition of thiols to activated alkynes, affords isolated high molar mass materials (>100 kDa) via step-growth polymerization with high levels of cis- or trans-double bond content. Furthermore, in various aspects of the present invention, it has been found that changing the monomer composition and chain end groups provides additional control over the materials' physical properties to provide more efficient compounding with polar additives. Using this approach to elastomer synthesis, further end group modification and toughening through various vulcanization strategies are also possible.
摘要:
In one or more embodiments, the present invention provides iodine-functionalized phenylalanine-based poly(ester urea)s (PEUs) (and related methods for their synthesis and use) that are metal free, degradable, radiopaque and suitable for use in surgical implants and other medical devices used within a patient. In one or more embodiment of the present invention 4-Iodo-L-phenylalanine and L-phenylalanine are separately reacted with 1,6-hexanediol to produce two monomers, bis-4-I-L-phenylalanine-1,6-hexanediol-diester (1-IPHE-6 monomer) and bis-L-phenylalanine-1,6-hexanediol-diester (1-PHE-6 monomer). It has been found that by varying the feed ratio of the 1-IPHE-6 and 1-PHE-6 monomers, the copolymer composition may be modulated to predictably create phenylalanine-based PEUs having a wide variation in thermal, mechanical and radiopacity properties. As most medical device procedures require placement verification via fluoroscopic imaging, materials that possess inherent X-ray contrast are valuable for a number of applications.
摘要:
In various embodiments, the present invention provides a strong, synthetic elastomer materials (and related methods for making same) with mechanical properties that are controlled by the stereochemically-defined double bonds within their backbone, yet have physical properties that are derived from monomer selection and defined, modifiable, chain end groups. The use of the organocatalyzed, stereospecific addition of thiols to activated alkynes, affords isolated high molar mass materials (>100 kDa) via step-growth polymerization with high levels of cis- or trans-double bond content. Furthermore, in various aspects of the present invention, it has been found that changing the monomer composition and chain end groups provides additional control over the materials' physical properties to provide more efficient compounding with polar additives. Using this approach to elastomer synthesis, further end group modification and toughening through various vulcanization strategies are also possible.
摘要:
A functional biologically active particle conjugate useful for diagnosis and treating cancer as a bioportal comprises a nanoscale particle having associated therewith an intracellular targeting ligand comprising a PNA, or another nuclease resistant oligonucleotide analog such as MOE-mRNA (2′-methoxyethyl mRNA) or LNA (locked nucleic acid), having a sequence that binds selectively to an uniquely expressed or overexpressed mRNA specific to the cancer or disease state in a living mammal. In one aspect the uniquely overexpressed target specific to the cancer or disease state is the unr mRNA which can be targeted by the antisense sequence PNA50.
摘要:
In various embodiments, the present invention relates to a series of anti-fouling zwitterionic biodegradable thiol-yne elastomers that incorporate degradable C4-C14 dicarboxylic acid-based monomer units made using a nucleophilic thiol-yne polymerization methodology that targets high cis-content at comparable molar masses to provide excellent mechanical properties and zwitterionic side chains that provide anti fouling properties. As each C4-C14 dicarboxylic acid-based monomer unit contains at least two labile ester linkages, altering the stoichiometry of degradable C4-C14 dicarboxylic acid-based monomer unit incorporation allows the degradation rate of the material to be tuned precisely, while retaining control over the mechanical properties by maintaining the cis/trans stereochemistry of the double bonds to provide independent tuning of mechanical and degradative properties.
摘要:
An pressure differential distribution system which offers an pressure differential reaction element (1) made of a comfortable, flexible pressure differential interface (2) that is attached to a support element (3), which in conjunction with a difference in pressure between the interior volume of the differential reaction element (1) can conform to various extended or reduced conformers. The flexible pressure differential interface (2) may retract within an enclosure(4). An emission removal adaptor (12) or terminal interface (23) may be coupled to a substance source (10) to capture or move substances on a pressure differential from a first zone to a second zone.
摘要:
In various embodiments, the invention relates to poly(propylene fumarate) (PPF)-based star-shaped copolymers synthesized using a core-first approach that uses a multi-functional alcohols as an initiator, and Mg(BHT)2(THF)2 as catalyst for controlled ring opening copolymerization (ROCOP) of maleic anhydride (MAn) with propylene oxide (PO). In some embodiments, these star-PPF copolymers have lower viscosities than their linear analogs, allowing a decrease in DEF fraction in resin formulation, as well as the use of higher molecular weights. These star-shape PPF can be used to prepare PPF:DEF resins containing as much as 70% by weight of the multi-arm PPF star copolymers, and have a low complex viscosity of high Mn star PPF resin that affords rapid printing with a Mn nearly eight times larger than the largest linear PPF oligomer printed previously.
摘要:
In one or more embodiments, the present invention provides iodine-functionalized phenylalanine-based poly(ester urea)s (PEUs) (and related methods for their synthesis and use) that are metal free, degradable, radiopaque and suitable for use in surgical implants and other medical devices used within a patient. In one or more embodiment of the present invention 4-Iodo-L-phenylalanine and L-phenylalanine are separately reacted with 1,6-hexanediol to produce two monomers, bis-4-I-L-phenylalanine-1,6-hexanediol-diester (1-IPHE-6 monomer) and bis-L-phenylalanine-1,6-hexanediol-diester (1-PHE-6 monomer). It has been found that by varying the feed ratio of the 1-IPHE-6 and 1-PHE-6 monomers, the copolymer composition may be modulated to predictably create phenylalanine-based PEUs having a wide variation in thermal, mechanical and radiopacity properties. As most medical device procedures require placement verification via fluoroscopic imaging, materials that possess inherent X-ray contrast are valuable for a number of applications.