Smart polymers have enormous potential in various applications.In particular,smart polymeric drug delivery systems have been explored as“intelligent”delivery systems able to release,at the appropriate time and site ...Smart polymers have enormous potential in various applications.In particular,smart polymeric drug delivery systems have been explored as“intelligent”delivery systems able to release,at the appropriate time and site of action,entrapped drugs in response to specific physiological triggers.These polymers exhibit a non-linear response to a small stimulus leading to a macroscopic alteration in their structure/properties.The responses vary widely from swelling/contraction to disintegration.Synthesis of new polymers and crosslinkers with greater biocompatibility and better biodegradability would increase and enhance current applications.The most fascinating features of the smart polymers arise from their versatility and tunable sensitivity.The most significant weakness of all these external stimuli-sensitive polymers is slow response time.The versatility of polymer sources and their combinatorial synthesis make it possible to tune polymer sensitivity to a given stimulus within a narrow range.Development of smart polymer systems may lead to more accurate and programmable drug delivery.In this review,we discuss various mechanisms by which polymer systems are assembled in situ to form implanted devices for sustained release of therapeutic macromolecules,and we highlight various applications in the field of advanced drug delivery.展开更多
Polymers are being used extensively in drug delivery due to their surface and bulk properties. They are being used in drug formulations and in drug delivery devices. These drug delivery devices may be in the form of i...Polymers are being used extensively in drug delivery due to their surface and bulk properties. They are being used in drug formulations and in drug delivery devices. These drug delivery devices may be in the form of implants for controlled drug delivery. Polymers used in colloidal drug carrier systems, consisting of small particles, show great advantage in drug delivery systems because of optimized drug loading and releasing property. Polymeric nano particulate systems are available in wide variety and have established chemistry. Non toxic, biodegradable and biocompatible polymers are available. Some nano particulate polymeric systems possess ability to cross blood brain barrier. They offer protection against chemical degradation. Smart polymers are responsive to atmospheric stimulus like change in temperature;pressure, pH etc. thus are extremely beneficial for targeted drug delivery. Some polymeric systems conjugated with antibodies/specific biomarkers help in detecting molecular targets specifically in cancers. Surface coating with thiolated PEG, Silica-PEG improves water solubility and photo stability. Surface modification of drug carriers e.g. attachment with PEG or dextran to the lipid bilayer increases their blood circulation time. Polymer drug conjugates such as Zoladex, Lupron Depot, On Caspar PEG intron are used in treatment of prostate cancer and lymphoblastic leukemia. Polymeric Drug Delivery systems are being utilized for controlled drug delivery assuring patient compliance.展开更多
Comprehensive Summary A disulfide-based poly(ether-b-amide)copolymer with rapid self-healing capability under moderate conditions was synthesized from 4,4’-dithiodibutyric acid(DTDBA),isophorondiamine(IPDA)and poly(t...Comprehensive Summary A disulfide-based poly(ether-b-amide)copolymer with rapid self-healing capability under moderate conditions was synthesized from 4,4’-dithiodibutyric acid(DTDBA),isophorondiamine(IPDA)and poly(tetramethylene oxide)(PTMO)based on a two-step method.The incorporation of IPDA with asymmetric structure and substantial steric hindrance not only effectively decreased the number of regular H-bonds,but also inhibited the crystallization of polyamide segments,imparting the synthesized poly(ether-b-amide)copolymer with an amorphous structural feature.Based on the coordination of segmental diffusion and recombination of disulfide bonds and hydrogen bonds,the scratches and damaged mechanical properties of PEBADS-I611 could be completely self-healed after healing at 40°C for only 11 min and 3 h,respectively.展开更多
Silicone rubber films were modified by the consecutive grafting of 2-(diethylamino)ethyl methacrylate (DEAEMA) and N-vinylcaprolactam (NVCL) using direct method on two steps with gamma-rays. The effect of absorbed dos...Silicone rubber films were modified by the consecutive grafting of 2-(diethylamino)ethyl methacrylate (DEAEMA) and N-vinylcaprolactam (NVCL) using direct method on two steps with gamma-rays. The effect of absorbed dose and monomer concentration on grafting degree was determined. The grafted samples were verified by FTIR-ATR spectroscopy and swelling;thermal properties were analyzed by DSC and TGA. The stimuli-responsive behavior was studied by swelling and/or DSC. Thermo- and pH-sensitive films of (PP-g-DEAEMA)-g-NVCL presented a pH critical at 3.2 and LCST around 63.5℃.展开更多
Gamma radiation has been shown particularly useful for the functionalization of surfaces with stimuli-responsive polymers. This method involves the formation of active sites (free radicals) onto the polymeric backbone...Gamma radiation has been shown particularly useful for the functionalization of surfaces with stimuli-responsive polymers. This method involves the formation of active sites (free radicals) onto the polymeric backbone as a result of the exposition to high-energy radiation, in which a proper microenvironment for the reaction among monomer and/or polymer and the active sites takes place, thus leading to propagation which forms side chain grafts. The modification of polymers using high-energy irradiation may be performed by the following methods: direct or simultaneous, pre-irradiation oxidative and pre-irradiation. The most frequent ones correspond to the pre-irradiation oxidative method and the direct one. Radiation-grafting has many advantages over conventional methods considering that it does not require catalyst nor additives to initiate the reaction, and in general, no changes on the mechanical properties with respect to the pristine polymeric matrix are observed. This chapter focused on the synthesis of smart polymers and coatings obtained by the use of gamma radiation. In addition, diverse applications of these materials in the biomedical field are also reported.展开更多
A review is presented in this paper on Shape Memory Polymers (SMPs) and their applications to smart, particularly textile products. Different kinds of SMPs developed by researchers around the world, characteristics of...A review is presented in this paper on Shape Memory Polymers (SMPs) and their applications to smart, particularly textile products. Different kinds of SMPs developed by researchers around the world, characteristics of SMPs and their applications, particularly to smart textiles are summarized. Current situations and potential application areas as well as future developments of smart textiles with shape memory polymers are discussed.展开更多
Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temp...Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature（LCST） is often sharp, which allows for a wide range of smart material applications.At the LCST, oligo（ethylene glycol）-substituted polyisocyanides（PICs） form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol（EG） tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.展开更多
文摘Smart polymers have enormous potential in various applications.In particular,smart polymeric drug delivery systems have been explored as“intelligent”delivery systems able to release,at the appropriate time and site of action,entrapped drugs in response to specific physiological triggers.These polymers exhibit a non-linear response to a small stimulus leading to a macroscopic alteration in their structure/properties.The responses vary widely from swelling/contraction to disintegration.Synthesis of new polymers and crosslinkers with greater biocompatibility and better biodegradability would increase and enhance current applications.The most fascinating features of the smart polymers arise from their versatility and tunable sensitivity.The most significant weakness of all these external stimuli-sensitive polymers is slow response time.The versatility of polymer sources and their combinatorial synthesis make it possible to tune polymer sensitivity to a given stimulus within a narrow range.Development of smart polymer systems may lead to more accurate and programmable drug delivery.In this review,we discuss various mechanisms by which polymer systems are assembled in situ to form implanted devices for sustained release of therapeutic macromolecules,and we highlight various applications in the field of advanced drug delivery.
文摘Polymers are being used extensively in drug delivery due to their surface and bulk properties. They are being used in drug formulations and in drug delivery devices. These drug delivery devices may be in the form of implants for controlled drug delivery. Polymers used in colloidal drug carrier systems, consisting of small particles, show great advantage in drug delivery systems because of optimized drug loading and releasing property. Polymeric nano particulate systems are available in wide variety and have established chemistry. Non toxic, biodegradable and biocompatible polymers are available. Some nano particulate polymeric systems possess ability to cross blood brain barrier. They offer protection against chemical degradation. Smart polymers are responsive to atmospheric stimulus like change in temperature;pressure, pH etc. thus are extremely beneficial for targeted drug delivery. Some polymeric systems conjugated with antibodies/specific biomarkers help in detecting molecular targets specifically in cancers. Surface coating with thiolated PEG, Silica-PEG improves water solubility and photo stability. Surface modification of drug carriers e.g. attachment with PEG or dextran to the lipid bilayer increases their blood circulation time. Polymer drug conjugates such as Zoladex, Lupron Depot, On Caspar PEG intron are used in treatment of prostate cancer and lymphoblastic leukemia. Polymeric Drug Delivery systems are being utilized for controlled drug delivery assuring patient compliance.
基金financially supported by the National Key Program of China(No.2022-1400600).
文摘Comprehensive Summary A disulfide-based poly(ether-b-amide)copolymer with rapid self-healing capability under moderate conditions was synthesized from 4,4’-dithiodibutyric acid(DTDBA),isophorondiamine(IPDA)and poly(tetramethylene oxide)(PTMO)based on a two-step method.The incorporation of IPDA with asymmetric structure and substantial steric hindrance not only effectively decreased the number of regular H-bonds,but also inhibited the crystallization of polyamide segments,imparting the synthesized poly(ether-b-amide)copolymer with an amorphous structural feature.Based on the coordination of segmental diffusion and recombination of disulfide bonds and hydrogen bonds,the scratches and damaged mechanical properties of PEBADS-I611 could be completely self-healed after healing at 40°C for only 11 min and 3 h,respectively.
文摘Silicone rubber films were modified by the consecutive grafting of 2-(diethylamino)ethyl methacrylate (DEAEMA) and N-vinylcaprolactam (NVCL) using direct method on two steps with gamma-rays. The effect of absorbed dose and monomer concentration on grafting degree was determined. The grafted samples were verified by FTIR-ATR spectroscopy and swelling;thermal properties were analyzed by DSC and TGA. The stimuli-responsive behavior was studied by swelling and/or DSC. Thermo- and pH-sensitive films of (PP-g-DEAEMA)-g-NVCL presented a pH critical at 3.2 and LCST around 63.5℃.
基金H.I.Melendez-Ortiz is grateful to the program Cátedras-CONACyT(Mexico)This chapter was supported by DGAPA-UNAM Grant IN200714+1 种基金CONACYT-CNPq Project 174378(Mexico)CNPq project number 490200/2011-7(Brazil).
文摘Gamma radiation has been shown particularly useful for the functionalization of surfaces with stimuli-responsive polymers. This method involves the formation of active sites (free radicals) onto the polymeric backbone as a result of the exposition to high-energy radiation, in which a proper microenvironment for the reaction among monomer and/or polymer and the active sites takes place, thus leading to propagation which forms side chain grafts. The modification of polymers using high-energy irradiation may be performed by the following methods: direct or simultaneous, pre-irradiation oxidative and pre-irradiation. The most frequent ones correspond to the pre-irradiation oxidative method and the direct one. Radiation-grafting has many advantages over conventional methods considering that it does not require catalyst nor additives to initiate the reaction, and in general, no changes on the mechanical properties with respect to the pristine polymeric matrix are observed. This chapter focused on the synthesis of smart polymers and coatings obtained by the use of gamma radiation. In addition, diverse applications of these materials in the biomedical field are also reported.
文摘A review is presented in this paper on Shape Memory Polymers (SMPs) and their applications to smart, particularly textile products. Different kinds of SMPs developed by researchers around the world, characteristics of SMPs and their applications, particularly to smart textiles are summarized. Current situations and potential application areas as well as future developments of smart textiles with shape memory polymers are discussed.
基金the Netherlands Organisation for Scientific Research (NWO)for providing and supporting beam time at the DutchBelgium beamline(DUBBLE) for SAXS experiments(No. BM26-02773)financial support from NWO (VENI grant No. 680-47-437)+2 种基金the Euopean Union's 2020 ResearchInnovation Programme under Grant Agreement No. 642687project Biogel
文摘Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature（LCST） is often sharp, which allows for a wide range of smart material applications.At the LCST, oligo（ethylene glycol）-substituted polyisocyanides（PICs） form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol（EG） tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.
