Polyorthoesters
In organic chemistry, an ortho ester is a functional group containing three alkoxy groups attached to one carbon atom, i.e. with the general formula RC(OR′)3. Orthoesters may be considered as products of exhaustive alkylation of unstable orthocarboxylic acids and it is from these that the name 'ortho ester' is derived. An example is ethyl orthoacetate, CH3C(OCH2CH3)3, more correctly known as … WebAug 30, 2024 · Many types of release delivery systems are available and known to those of ordinary skill in the art. They include, for example, polymer-based systems such as polylactic and/or polyglycolic acids, polyanhydrides, polycaprolactones, copolyoxalates, polyesteramides, polyorthoesters, polyhydroxybutyric acid, and/or combinations of these.
Polyorthoesters
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WebA diagnostic method of monitoring anti-inflammatory and/or antioxidant actions of therapeutic agents comprises determining the level of at least one systemic marker indicative of inflammation or oxidation in a bodily sample taken from a subject at base line or following administration of the therapeutic agent. The marker includes at least one of … WebFeb 19, 2024 · A population of polymeric particles for controlled release of therapeutic agents which have unacceptable toxicity when administered intravitreally can be safely administered suprachoroidally at the same intravitreal concentration or dose. In a preferred embodiment, the particles have a high loading of the agent and is released without a …
WebWO2024037172A1 PCT/IB2024/055035 IB2024055035W WO2024037172A1 WO 2024037172 A1 WO2024037172 A1 WO 2024037172A1 IB 2024055035 W IB2024055035 W IB 2024055035W WO 2024037172 A1 WO2024037172 A1 WO 2024037172A1 Authority WO WIPO (PCT) Prior art keywords weight percent blended composition poly melt phenylene … WebMay 11, 2001 · Likewise, preferred polyorthoesters for more solid compositions are those in which the “hard” or “hydrogen bonding” unit constitutes from about 60 mole percent to about 99.9 mole percent. Polyorthoesters having a higher content of the “α-hydroxy acid containing” unit will have a higher rate of bioerodibility.
WebSep 28, 2015 · [0002] The use of prosthetic implants e.g. for replacing or supplementing fractured, damaged, or degenerated skeletal bone in a mammalian body is commonplace in the medical arts. Usually, the prosthetic implant device is made of a biocompatible metal such as stainless steel, cobalt-chromium-molybdenum alloy, tungsten, titanium, … WebAseries of new oligomeric polyorthoesters for low-VOC coatings was prepared by protecting OH groups with orthoester compounds to achieve both low viscosity and excellent com-patibility with crosslinking agents. These new oligomeric polyorthoesters were synthesized through a co-condensation reaction among polyol, orthoester, anda- orb-glycol com -
Polyorthoesters are polymers with the general structure –[–R–O–C(R1, OR2)–O–R3–]n– whereas the residue R2 can also be part of a heterocyclic ring with the residue R. Polyorthoesters are formed by transesterification of orthoesters with diols or by polyaddition between a diol and a diketene acetal, … See more Polyorthoesters are used as hydrophobic implant materials for drug depots for continuous drug delivery by surface erosion. The active ingredient (which is homogeneously dispersed in a matrix of polyorthoester) … See more 1st generation polyorthoester (POE I) Polyorthoester type I is (usually) obtained by transesterification of an α,ω-diol with 2,2-diethoxytetrahydrofuran See more • Biodegradable Polymers as Drug Delivery Systems, in Drugs and the Pharmaceutical Sciences, vol. 45, Marcel Dekker, Inc., 1990, See more
WebPolyorthoesters are generally considered to be highly biocompatible, surface-eroding materials. However, sensitive intermediates and poor mechanical performance have … greece packages 2023 from indiaWebApr 6, 2024 · Biodegradable, biocompatible polymers can be used, such as polyanhydrides, polyglycolic acid, polyorthoesters, and polylactic acid. In general, each active agent is formulated, dosed, and administered in therapeutically effective amount using pharmaceutical compositions and dosing regimens that are consistently with good … greece owlWebJan 1, 2005 · The synthesis and characterization of four distinct families of poly (ortho esters) are described and designated as poly (ortho esters) I, II, III and IV. Poly (ortho ester) I is prepared by the transesterification of diethoxytetrahydrofuran with diols. Poly (ortho ester) II is prepared by the condensation of 3,9-bis (ethylidene 2,4,8,10 ... florists south paris maineWebTissue engineering often utilizes biodegradable polymers in the form of porous scaffolds for regenerating de novo tissues. There is an ever-increasing need for biodegradable polymers as temporary substrates for facilitating tissue regeneration. Compared to the widely used polyesters, polyorthoesters, poly(α- florists st austell cornwallWebSep 17, 2024 · Polyorthoesters are generally considered to be highly biocompatible, surface-eroding materials. However, sensitive intermediates and poor mechanical performance … greece packages from torontoWeb7.2.2.5 Polyorthoesters. Being amorphous, hydrophobic, and biodegradable polymers, polyorthoesters have many specific features like surface wearing down mechanism (removal of upper surface gradually deposing new surfaces by deformation) and pH sensitive degeneration rate (Lyu and Untereker, 2009). greece packages 2023 singapore travel agenWebApr 13, 2015 · Synthesis of Rapidly Surface Eroding Polyorthoesters and Polyacetals Using Thiol–ene Click Chemistry. ACS Macro Letters 2024, 8 (10) , 1268-1274. DOI: … greece package holidays 2019