Peptides ; chemistry ; Polyethylene Glycols ; chemistry ; Proteins ; chemistry

Polyetheretherketone (PEEK) has been widely applied in orthopedics because of its excellent mechanical properties, radiolucency, and biocompatibility. However, the bioinertness and poor osteointegration of PEEK have greatly limited its further application. Growing evidence proves that physical factors of implants, including their architecture, surface morphology, stiffness, and mechanical stimulation, matter as much as the composition of their surface chemistry. This review focuses on the multiple strategies for the physical modification of PEEK implants through adjusting their architecture, surface morphology, and stiffness. Many research findings show that transforming the architecture and incorporating reinforcing fillers into PEEK can affect both its mechanical strength and cellular responses. Modified PEEK surfaces at the macro scale and micro/nano scale have positive effects on cell-substrate interactions. More investigations are necessary to reach consensus on the optimal design of PEEK implants and to explore the efficiency of various functional implant surfaces. Soft-tissue integration has been ignored, though evidence shows that physical modifications also improve the adhesion of soft tissue. In the future, ideal PEEK implants should have a desirable topological structure with better surface hydrophilicity and optimum surface chemistry.
Benzophenones ; Ketones/chemistry* ; Polyethylene Glycols/chemistry* ; Polymers/chemistry* ; Surface Properties

Polyetheretherketone (PEEK) is a polymer material composed of aromatic rings connected by ether and ketone groups. It has advantages of excellent biocompatibility, stable chemical properties, and appropriate elasticity modulus. Since PEEK are increasingly used in dentistry in recent years, the properties, modification methods, and research advances of them in oral implantology were discussed in this review.
Dental Implants ; Polymers ; Ketones/chemistry* ; Polyethylene Glycols/chemistry* ; Ethers

To investigate theological properties of common hydrophilic gel excipients such as Carbopol based on viscosity, the viscosity was determined by rotation method and falling-ball method. Linear regression was made between ln(eta) and concentration, the slope of which was used to explore the relation between viscosity and concentration of different excipients. The viscosity flow active energy (E(eta)) was calculated according to Arrhenius equation and was used to investigate the relation between viscosity and temperature of different excipients. The results showed that viscosities measured by two methods were consistent. Concentration of guargum (GG) and hydroxypropylmethyl cellulose (HPMC) solution had a great influence on the viscosity, k > 5; while concentration of polyvinylpyrrolidone-K30 (PVP-K30) and polyethylene glycol 6000 (PEG6000) exerted a less effect on viscosity, k < 0.2; viscosity flow active energy of different excipients were close, which ranged from 30 to 40 kJ x mol(-1). Therefore, theological properties study could provide the basis for application of excipients and establish a foundation for the research of relation between excipients structure, property and function.
Excipients ; chemistry ; Gels ; chemistry ; Polyethylene Glycols ; chemistry ; Polyvinyls ; chemistry ; Povidone ; chemistry ; Rheology ; Temperature ; Viscosity

Polyethylene glycol (PEG) lipid derivatives could increase the stability of liposomes in vivo and in vitro and prolong the circulation time of liposomes in vivo. However, the chemical bond between PEG and lipid was so stable that liposomes modified with traditional PEG-lipid derivatives could not release their contents at targeted tissue immediately and the pharmacodynamic effect was reduced. The concept of cleavable PEG-lipid was raised in recent years and these PEG-lipid derivatives could break under physiological or pathological condition. The cleavable PEG-lipid derivatives could prolong the circulation time of liposomes, and after arriving at targeted location, PEG fragment had cleaved from the surface of liposomes, so liposomes could bind with pathological cells and release contents into cells. Removal of the protective polymer layer is necessary once the liposome close to the tumour to allow to fuse and release drug. Attempts have been made to increase the circulation time and reconstitute the cellular affinity of liposomes by incorporating PEG-lipid derivatives. This review focused on the kinds of cleavable PEG-lipid derivatives, types of cleavage, the application feature to liposomes and the advantages and localizations.
Cholesterol ; analogs & derivatives ; chemistry ; Drug Delivery Systems ; methods ; Humans ; Liposomes ; chemistry ; Phosphatidylethanolamines ; chemistry ; Polyethylene Glycols ; chemistry

With the continuous exploration of microemulsions as solvents for traditional Chinese medicine extraction, polyoxyethy-lene(35) castor oil(CrEL), a commonly used surfactant, is being utilized by researchers. However, the problem of detecting residues of this surfactant in microemulsion extracts has greatly hampered the further development of microemulsion solvents. Based on the chemical structures of the components in CrEL and the content determination method of castor oil in the 2020 edition of the Chinese Pharmacopoeia(Vol. Ⅳ), this study employed gas chromatography(GC) and single-factor experiments to optimize the preparation method of methyl ricinoleate from CrEL. The conversion coefficient between the two was validated, and the optimal sample preparation method was used to process microemulsion extracts of Zexie Decoction from three batches. The content of methyl ricinoleate generated was determined, and the content of CrEL in the microemulsion extracts of Zexie Decoction was calculated using the above conversion coefficient. The results showed that the optimal preparation method for CrEL was determined. Specifically, 10 mL of 1 mol·L~(-1) KOH-methanol solution was heated at 60 ℃ for 15 min in a water bath. Subsequently, 10 mL of boron trifluoride etherate-methanol(1∶3) solution was heated at 60 ℃ for 15 min in a water bath, followed by extraction with n-hexane twice. CrEL could stably produce 20.84% methyl ricinoleate. According to this conversion coefficient, the average mass concentration of CrEL in the three batches of Zexie Decoction microemulsion extracts was 11.94 mg·mL~(-1), which was not significantly different from the CrEL mass concentration of 11.57 mg·mL~(-1) during microemulsion formulation, indicating that the established content determination method of this study was highly accurate, sensitive, and repeatable. It can be used for subsequent research on microemulsion extracts of Zexie Decoction and provide a reference for quality control of other drug formulations containing CrEL.
Polyethylene Glycols/chemistry* ; Castor Oil ; Methanol ; Surface-Active Agents/chemistry* ; Solvents ; Water/chemistry* ; Emulsions/chemistry*

A novel Cu-IUDs material, PU/PEG/Cu nanocomposite, was prepared by melt blending method with thermoplastic polyurethane (PU) as the matrix, with polyethylene glycol (PEG) as a hydrophilic modifier, and with nanometer particles of copper as active matter instead of copper wire or copper tube. The structure, morphology, mechanical properties, thermal stability and water absorption were investigated by using FT-IR, XRD, SEM and so on. The results indicated that the nanometer particles of copper were uniformly dispersed in the matrix in PU/PEG/ Cu nanocomposites. It can be seen that the water absorption ability of this nanocomposite was obviously improved while mechanical properties and thermal stability were at high levels. These results provided a good basis for the studies on the cupric ions release of the nanocomposites in future.
Biocompatible Materials ; chemistry ; Intrauterine Devices, Copper ; Nanocomposites ; chemistry ; Polyethylene Glycols ; chemistry ; Polyurethanes ; chemistry

Polyethylene glycol (PEG) is extensively used to increasing the in vivo and in vitro stability of liposomes. However, PEGylated liposomes also produce some negative effects with further research, such as low cellular uptake, poor "endosomal escape" of pH sensitive liposome (PSL) and accelerated blood clearance (ABC) phenomenon, and this situation is referred as the "PEG dilemma". "PEG dilemma" posed severe challenges for the targeted delivery of PEGylated liposomes-loaded anticancer drugs, effective intracellular release of PEGylated PSL-encapsulated gene and protein drugs, and repeated administration of PEGylated liposomes. Therefore, it is urgent to solve the "PEG dilemma". This review focused on the definition, classification of "PEG dilemma", and discussed several possible approaches to overcome "PEG dilemma".
Antineoplastic Agents ; chemistry ; Drug Carriers ; chemistry ; Liposomes ; chemistry ; Polyethylene Glycols ; chemistry

A novel oral delivery system that TPGS modified docetaxel proniosomes, DTX-TPGS-PN, was developed and the characterization after hydration was observed. Firstly, Doce-TPGS-PN was optimized by investing the factors, including the type of surfactant, methods of adding TPGS, content of TPGS and the molar ratio of span40/cholesterol, which may affecting the particle size, encapsulation efficiency and instantaneous release of drug in the formulation. Then, the morphology, particle size, Zeta potential, encapsulation efficiency and in vitro release of the formulation were evaluated. The result showed that hydrated nanoparticles of DTX-TPGS-PNs were (93 ± 6.5) nm in size,(-83.95 ± 3.69) mV in zeta potential, (97.31 ± 0.60)% in encapsulation efficiency, exhibiting spherical morphology and biphasic release process that a low burst effect within the first 0.5 hour and a relative-sustained release for the next several hours in PBS. These results indicate the oral delivery system of DTX-TPGS-PN was successfully built with good properties.
Chemistry, Pharmaceutical ; methods ; Particle Size ; Polyethylene Glycols ; chemistry ; Taxoids ; chemistry ; pharmacology ; Vitamin E ; analogs & derivatives ; chemistry

OBJECTIVETo prepare an effective and water-soluble lubricant.

METHODCo-sprayed lubricant (L-leucine and polyethylene glycol 6000 co-sprayed according to a certain proportion) and mixed lubricant (the physical mixture of spayed L-leucine and crushed polyethylene glycol 6000) were prepared and polyethylene glycol 6000, L-leucine, magnesium stearate, sodium stearyl fumarate and sodium chloride are crushed and sieved, respectively. Residual force, appearance of solution and disintegration time were considered as response variables of the lubrication effect to evaluate different lubricants. The changes of the co-sprayed lubricant were studied by differential scanning calorimetry, fourier infrared, electronic scanning microscope and X-ray diffraction.

RESULTThe efficacy of co-sprayed lubricant is better than other lubricants. Efficacy is improved by external form change without inner components and crystal changes.

CONCLUSIONCo-sprayed lubricant is a good water soluble tablet lubricant which has good efficacy.

Chemistry, Pharmaceutical ; Leucine ; chemistry ; Lubricants ; chemistry ; Polyethylene Glycols ; chemistry ; Solubility ; Tablets ; Water ; X-Ray Diffraction