Polyhydroxyalkanoates (PHAs) are excellent candidate biomaterials due to their exceptional biodegradability and biocompatibility. However, PHAs need to have tunable hydrophilicity, chemical ...functionalities, and appropriate hydrolytic stability to expand their therapeutic applications towards more advanced areas. In this Tutorial Review, we present the most recent progress in the synthetic strategies of PHA-based water soluble polymers, including the functionalisation of PHAs with polar functional groups and the block/graft copolymerization of PHAs with hydrophilic components in various polymeric architectures. These chemically modified water soluble PHAs have significant impact on materials engineering and show great value in the fulfilment of smart biomaterials in emerging areas. The applications of water soluble PHAs in controlled drug release, cancer therapy, DNA/siRNA delivery and tissue engineering in new aspects are discussed. In addition, water soluble PHA monomer production will be briefly introduced, with emphasis on its bio-significance in medical physiology and the therapeutic effect in the treatment of diseases.
The development of hybrid biomaterials has been attracting great attention in the design of materials for biomedicine. The nanosized level of inorganic and organic or even bioactive components can be ...combined into a single material by this approach, which has created entirely new advanced compositions with truly unique properties for drug delivery. The recent advances in using hybrid nanovehicles as remotely controlled therapeutic delivery carriers are summarized with respect to different nanostructures, including hybrid host–guest nanoconjugates, micelles, nanogels, core–shell nanoparticles, liposomes, mesoporous silica, and hollow nanoconstructions. In addition, the controlled release of guest molecules from these hybrid nanovehicles in response to various remote stimuli such as alternating magnetic field, near infrared, or ultrasound triggers is further summarized to introduce the different mechanisms of remotely triggered release behavior. Through proper chemical functionalization, the hybrid nanovehicle system can be further endowed with many new properties toward specific biomedical applications.
The development of hybrid biomaterials has been attracting great attention in the design of materials for biomedicine. The most recent advances of using hybrid nanovehicles as remotely controlled therapeutic delivery system are summarized.
Coacervation is a process during which a homogeneous aqueous solution undergoes liquid–liquid phase separation, giving rise to two immiscible liquid phases composed of a colloid‐rich coacervate phase ...in equilibrium with a colloid‐poor phase simultaneously. Recent attempts to develop complex coacervation from macromolecular self‐assemblies have diversified a large group of novel coacervate‐related materials with sophisticated properties and emerging applications. In this review, the most recent progress in the design strategies of macromolecular complex coacervation is discussed with respect to different key parameters, including macromolecular structure, mixing ratio, ionic strength, pH, and temperature, etc. Furthermore, the applications of these multiple‐functional coacervate materials, oriented toward advanced encapsulation, are further summarized into several active domains in wastewater treatment, protein purification, food formulation, underwater adhesives, drug delivery, and cellular mimics. Finally, perspectives and future challenges related to the further advancement of macromolecular complex coacervates are proposed.
A comprehensive overview of recent work on complex coacervation from macromolecular assemblies, with a focus on coacervate mechanics, design strategies, and influence factors on their formation, is provided. Furthermore, recent achievements on representative applications of coacervate‐based materials in a broad range of fields are highlighted.
Biomaterials is an exciting and dynamic field, which uses a collection of diverse materials to achieve desired biological responses. While there is constant evolution and innovation in materials with ...time, biomaterials research has been hampered by the relatively long development period required. In recent years, driven by the need to accelerate materials development, the applications of machine learning in materials science has progressed in leaps and bounds. The combination of machine learning with high‐throughput theoretical predictions and high‐throughput experiments (HTE) has shifted the traditional Edisonian (trial and error) paradigm to a data‐driven paradigm. In this review, each type of biomaterial and their key properties and use cases are systematically discussed, followed by how machine learning can be applied in the development and design process. The discussions are classified according to various types of materials used including polymers, metals, ceramics, and nanomaterials, and implants using additive manufacturing. Last, the current gaps and potential of machine learning to further aid biomaterials discovery and application are also discussed.
The advancement of machine learning (ML) in materials science has progressed in leaps and bounds and has made a big impact into biomaterials research, ranging from discovery of bioactive chemical moieties, screening and optimization of material properties, to developing materials that interface better with biological systems. There is still untapped potential to integrate with ML for the next frontier in biomaterials.
A highly tunable nanoparticle (NP) system with multifunctionalities was developed as drug nanocarrier via a facile layer-by-layer (LbL) stereocomplex (SC) self-assembly of enantiomeric poly(l-lactic ...acid) (PLLA) and poly(d-lactic acid) (PDLA) in solution using silica-coated magnetite (Fe3O4@SiO2) as template. The poly(lactide) (PLA) SC coated NPs (Fe3O4@SiO2@-SC) were further endowed with different stimuli-responsiveness by controlling the outermost layer coatings with respective pH-sensitive poly(lactic acid)-poly(2-dimethylaminoethyl methacrylate) (PLA-D) and temperature-sensitive poly(lactic acid)-poly(N-isopropylacrylamide) (PLA-N) diblock copolymers to yield Fe3O4@SiO2@SC-D and Fe3O4@SiO2@SC-N NPs, respectively, while the superparamagnetic properties of Fe3O4 were maintained. TEM images show a clearly resolved core-shell structure with a silica layer and sequential PLA SC co/polymer coating layers in the respective NPs. The well-designed NPs possess a size distribution in a range of 220-270 nm and high magnetization of 70.8-72.1 emu/g Fe3O4. More importantly, a drug release study from the as-constructed stimuli-responsive NPs exhibited sustained release profiles and the rates of release can be tuned by variation of external environments. Further cytotoxicity and cell culture studies revealed that PLA SC coated NPs possessed good cell biocompatibility and the doxorubicin (DOX)-loaded NPs showed enhanced drug delivery efficiency toward MCF-7 cancer cells. Together with the strong magnetic sensitivity, the developed hybrid NPs demonstrate a great potential of control over the drug release at a targeted site. The developed coating method can be further optimized to finely tune the nanocarrier size and operating range of pHs and temperatures for in vivo applications.
While small hydrophilic therapeutic molecules have proved to be exceptionally effective in curing diseases, their
in vivo
efficacy remains low. Small molecule therapeutics infused
in vivo
result in ...uncontrolled bio-distribution that causes dilution and unwanted side effects. Therefore, global research to search for ideal carriers for small molecule therapeutics has gained attention seeking to increase efficiency of targeting desired cells. Liposomes are one class of nanocarriers that could encapsulate both hydrophilic and lipophilic small molecule therapeutics, protect them against physiological degradation and deliver them into targeted cells. In this review, studies done from the past up to the present are summarized, and various methods and mechanisms for encapsulation of small therapeutic molecules in liposomes for targeted delivery and triggered release, as well as their potential in the clinical uses, will be discussed.
In this review, various methods and mechanisms for encapsulation of small therapeutic molecules in liposomes for targeted delivery and triggered release, as well as their potential in the clinical uses, are discussed.
In recent years, naturally biodegradable polyhydroxyalkanoate (PHA) monopolymers have become focus of public attentions due to their good biocompatibility. However, due to its poor mechanical ...properties, high production costs, and limited functionality, its applications in materials, energy, and biomedical applications are greatly limited. In recent years, researchers have found that PHA copolymers have better thermal properties, mechanical processability, and physicochemical properties relative to their homopolymers. This review summarizes the synthesis of PHA copolymers by the latest biosynthetic and chemical modification methods. The modified PHA copolymer could greatly reduce the production cost with elevated mechanical or physicochemical properties, which can further meet the practical needs of various fields. This review further summarizes the broad applications of modified PHA copolymers in biomedical applications, which might shred lights on their commercial applications.
In recent years, naturally biodegradable polyhydroxyalkanoate (PHA) monopolymers have become the focus of public attention due to their good biocompatibility. This review summarizes the synthesis of a range of PHA copolymers by the latest biosynthetic and chemical modification methods. This review further summarizes the broad application of modified PHA copolymers in biomedical applications and highlights its latest applications in biomedical applications. This article is part of an AFOB (Asian Federation of Biotechnology) Special issue. To learn more about the AFOB visit www.afob.org.
A cyclodextrin-based supramolecular hydrogel system with supramolecularly anchored active cationic copolymer/plasmid DNA (pDNA) polyplexes was studied as a sustained gene delivery carrier. A few ...biodegradable triblock copolymers of methoxy-poly(ethylene glycol)-b-poly(ε-caprolactone)-b-poly2-(dimethylamino)ethyl methacrylate (MPEG-PCL-PDMAEMA) with well-defined cationic block lengths were prepared to condense pDNA. The MPEG-PCL-PDMAEMA copolymers exhibit good ability to condense pDNA into 275-405 nm polyplexes with hydrophilic MPEG in the outer corona. The MPEG corona imparted greater stability to the pDNA polyplexes and also served as an anchoring segment when the pDNA polyplexes were encapsulated in α-CD-based supramolecular polypseudorotaxane hydrogels. More interestingly, the resultant hydrogels were able to sustain release of pDNA up to 6 days. The pDNA was released in the form of polyplex nanoparticles as it was bound electrostatically to the cationic segment of the MPEG-PCL-PDMAEMA copolymers. The bioactivity of the released pDNA polyplexes at various durations was further investigated. Protein expression level of pDNA polyplexes released over the durations was comparable to that of freshly prepared PEI polyplexes. Being thixotropic and easily prepared without using organic solvent, this supramolecular in situ gelling system has immense potential as an injectable carrier for sustained gene delivery.
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