This study aims to investigate the preparation process and in vitro release behavior of artesunate polylactic acid microspheres, in order to prepare an artesunate polylactic acid (PLA) administration method suitable for hepatic arterial embolization. With PLA as the material and polyvinyl alcohol (PVA) as the emulsifier, O/W emulsion/solvent evaporation method was adopted to prepare artesunate polylactic acid microspheres, and optimize the preparation process. With drug loading capacity, encapsulation efficiency and particle size as indexes, a single factor analysis was made on PLA concentration, PVA concentration, drug loading ratio and stirring velocity. Through an orthogonal experiment, the optimal processing conditions were determined as follows: PLA concentration was 9. 0% , PVA concentration was 0. 9% , drug loading ratio was 1:2 and stirring velocity was 1 000 r x min(-1). According to the verification of the optimal process, microsphere size, drug loading and entrapment rate of artesunate polylactic acid microspheres were (101.7 +/- 0.37) microm, (30.8 +/- 0.84)%, (53.6 +/- 0.62)%, respectively. The results showed that the optimal process was so reasonable and stable that it could lay foundation for further studies.
Artemisinins ; chemistry ; Calibration ; Drug Compounding ; methods ; Lactic Acid ; chemistry ; Microspheres ; Polyesters ; Polymers ; chemistry ; Polyvinyl Alcohol ; chemistry

OBJECTIVETo investigate the structure and degradation property of the polyvinyl alcohol (PVA)-collagen complex drug membrane.

METHODSDrug collagen membrane was complexed with PVA. The physical and chemical properties of the membrane were characterized by transmission electron microscopy, scanning electron microscope, forier transform-infrared spectroscopy and differential scanning calorimetry. Degradation experiment was performed to determine the degradation property of membrane and a degradation curve was therefor drawn.

RESULTSThe thermodynamic stability of collagen membrane was not destroyed by adding PVA. Collagen had good compatibility with PVA. Compared with collagen membrane, collagen-PVA complex membrane had smaller and evener pores. Adding PVA decreased the degradation rate of membrane.

CONCLUSIONSPVA-collagen membrane has better microstructure and antidegradation property than collagen membrane.

Biocompatible Materials ; chemistry ; Collagen ; chemistry ; ultrastructure ; Humans ; Membranes ; Polyvinyl Alcohol ; chemistry ; Spectroscopy, Fourier Transform Infrared

This study sought to explore a new compound polyvinyl alcohol-collagen as a wound dressing. To make the polymer, Polyvinyl alcohol (PVA) and collagen type I were put together in the ratio of 3:1, at the same time, polyethlene glycol as porogen was added, and the material was dried by air to be a membrane in shape. Then the ultimate tensile load, the hole diameter, porosity, and water absorption were measured. The cell biocompatibility was tested as well. The results showed the PVA-collagen blend had the average hole 100-150 microm in diameter, and the porosity about 90%. The ultimate tensile load reached 8.10 +/- 0.28 MPa, and water absorption was up to 185.42% +/- 6.93%. 3T3 cells grew well on the PVA-collagen member. Therefore, the PVA-collagen memberane is characterized not only by its ideal biomechanical ability and biocompability, but also by its ideal hole diameter, porosity and water absorption. It may have the potential for use as a wound dressing in vivo.
Biocompatible Materials ; chemical synthesis ; chemistry ; Collagen ; chemistry ; Humans ; Occlusive Dressings ; Polyvinyl Alcohol ; chemistry

OBJECTIVE: To explore the feasibility of preparing different doses of tablets for personalized treatment by fused deposition modeling (FDM) 3D printing technology, and to evaluate the in vitro quality of the FDM 3D printed tablets. METHODS: Three different sizes of hollow tablets were prepared by fused deposition modeling 3D printing technology with polyvinyl alcohol (PVA) filaments. Theophylline was chosen as the model drug. In the study, 20 mg, 50 mg and 100 mg of theophylline was filled into the cavity of the tablets, respectively. The microscopic morphology of the tablets was observed by scanning electron microscopy (SEM). The weight variation of the tablets was investigated by weighing method. The hardness of the tablets was measured by tablet hardness tester. The contents of the drugs in the tablets were determined by ultraviolet and visible spectrophotometry (UV-Vis), and the dissolution apparatus was used to assay the in vitro drug release of the tablets. RESULTS: The prepared FDM 3D printed tablets were all in good shape without printing defects. And there was no leakage phenomenon. The diameter and thickness of the tablets were consistent with the design. The layers were tightly connected, and the fine structure of the formulation could be clearly observed without printing defects by scanning electron microscopy. The average weight of the three sizes of tablets was (150.5±2.3) mg, (293.6±2.6) mg and (456.2±5.6) mg, respectively. The weight variation of the three sizes of tablets were boss less than 5%, which met the requirements; The hardness of the tablets all exceeded 200 N; The contents of theophylline in the three tablets were 98.0%, 97.2% and 97.9% of the dosage (20 mg, 50 mg and 100 mg), and the relative standard deviation (RSD) was 1.06%, 1.15% and 0.63% respectively; The time for 80% drug released from the three dosage of tablets was within 30 min. CONCLUSION Three different dosages of theophylline tablets were successfully prepared by FDM 3D printing technology in this study. The exploration may bring beneficial for the preparation of personalized dose preparations. We expect that with the development of 3D printing technology, FDM 3D printed personalized tablets can be used in the clinic as soon as possible to provide personalized treatment for patients.
Humans ; Theophylline/chemistry* ; Tablets/chemistry* ; Drug Liberation ; Printing, Three-Dimensional ; Polyvinyl Alcohol/chemistry* ; Technology, Pharmaceutical/methods*

Gelatin and hydroxyapatite were introduced to polyvinyl alcohol (PVA) hydrogel with an attempt to enhance the performances of PVA hydrogel. Through a reiterative freezing-thawing methods, three kinds of PVA composite hydrogels were prepared. The mechanical performances of these composite hydrogels with the same PVA and HA content but varying gelatin content, such as tensile strength, elasticity modulus, creep curve, relaxation curve and friction coefficient were evaluated by using a computer-controlled universal electronic mechanical testing machine and a UMT-II frictional testing machine. The additional effects of hydroxylapatite and varying gelatin on the performances of composite PVA hydro-gels were analyzed. It was found that the gelatin content directly influenced the physical performances of PVA composite hydrogels; but no linear relationship was recorded. PVA composite hydrogel containing 2wt-% gelatin gave optimal results, i.e. tensile strength of 5.5MPa, compressive elastical modulus of 1.48MPa, creeping rate of 31% in 45 minutes, stress relaxing rate of 40.3%, and the starting friction coefficient of 0.332.
Elastic Modulus ; Friction ; Hydrogels ; chemical synthesis ; chemistry ; Mechanical Phenomena ; Polyvinyl Alcohol ; chemical synthesis ; chemistry ; Tensile Strength

Based on casting and solvent evaporation method, the degradable PLA/PVA blend film was prepared with polylactic acid (PLA) and polyvinyl alcohol (PVA) as raw material. The moisture absorbability, water absorbability and degradability of the polylactic acid/polyvinyl alcohol (PLA/PVA) blend film were studied; also the degradation mechanism of blend film was investigated. The results showed that the moisture absorption and water absorption of blend film decreased as the concentration of PLA increased. The degradation process of blend film in the normal saline is conducted by stepwise. At the forepart, the degradation of PLA played an important role, while PVA was the main degradation substance later. The solvent acidity could catalyze the degradation of PLA, and degradation of PLA was always turning from noncrystalline region to crystalline region. PVA had abilities to accelerate the degradation of PLA by increasing the hydrophilicity of the blend film and by breaking the crystallinity of PLA. Therefore, the hydrophilicity and degradability of PLA/PVA blend film can be controlled in a certain range by adjusting the proportion of PLA and PVA.
Biocompatible Materials ; chemistry ; Biodegradation, Environmental ; Hydrophobic and Hydrophilic Interactions ; Lactic Acid ; chemistry ; Polyesters ; chemistry ; Polymers ; chemistry ; Polyvinyl Alcohol ; chemistry ; Water ; chemistry

Porous HA ceramics were prepared by using NH4 HCO3/PVA as pore-formed material along with biological glass as intensifier, and these ceramics were immersed in Locke's Physiological Saline and Simulate Body Fluid (SBF). The changes of phase composition, grain size and crystallinity of porous HA ceramics before and after immersion were investigated by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The biological activity was evaluated. The porous HA ceramics showed various degrees of decomposition after immersion in the two solution systems, but there was no evident change in respect to crystallinity. Besides, the impact of different degrees of solution systems on the change of grain size and planar preferred orientation was observed. The TCP phase of the ceramics immersed in Locke's Physiological Saline decomposed and there was no crystal growth on the surface of ceramics; however, the grain size of ceramics immersed in SBF became refined in certain degree and the surface of ceramics took on the new crystal growth.
Bicarbonates ; chemistry ; Biomimetic Materials ; chemical synthesis ; chemistry ; Ceramics ; chemical synthesis ; chemistry ; Durapatite ; chemical synthesis ; chemistry ; Polyvinyl Alcohol ; chemistry ; Porosity

This paper explicated the present application of poly- vinyl alcohol (PVA) in the field of biomedical engineering, such as artificial cartilage, drug delivery systems, microorganism enwrapping, cell micro-capsulation, anti-thrombin materials, and biomedical sponges. And a preliminary study of the good dispersion of PVA as a surfactant on nano-particles of hydroxyapatite was presented.
Artificial Organs ; Biocompatible Materials ; Biomedical Engineering ; Drug Compounding ; Drug Delivery Systems ; Durapatite ; chemistry ; Materials Testing ; Nanoparticles ; chemistry ; Polyvinyl Alcohol ; chemistry

In this study the poly(vinyl alcohol)(PVA) hydrogel elastomer was prepared by freezing-thawing method. The influences of percentage of poly (vinyl alcohol) in hydrogel, pH of solution and swelling temperature upon the swelling characteristic of PVA-hydrogel prosthetic nucleus material were studied. Its micropores were observed using SEM, and the swelling dynamics was further discussed. The experimental results showed that the poly (vinyl alcohol) hydrogel was a kind of network with a lot of micropores, the pore size was related with the PVA content. The maximum swelling ratio decreases when the percentage of PVA in hydrogel, the pH of solution and the swelling temperature were enhanced. The swelling process was described by the equation of swelling dynamics equation. The swelling rate was greatly influenced by the PVA content, the pH of solution and the dimension of hydrogel sample.
Biocompatible Materials ; chemistry ; Hydrogels ; Hydrogen-Ion Concentration ; Implants, Experimental ; Intervertebral Disc ; Polyvinyl Alcohol ; chemistry ; Prostheses and Implants ; standards

As a drug additive, polyvinyl alcohol(PVA) has merits of solubility, easy forming, strong conglutination, high thermal stability, low toxicity and no irritation. In these years, PVA has been applied wider and wider in medicine industry. In the study of modem preparations of TCM PVA, as film material of membrane and pellicles, is very promising owing to its easy forming and excellent toughness. PVA is good polymer matrix for suppositories and gel, because it can not only carry drug but also improve the properties of preparations on application and technology. It can be said that PVA is an excellent carrier. At the present, PVA is mainly applied in vitro preparations of TCM, but its applications will be spread with further research. The prospective applications of PVA in osmotic pump controlled release preparations, drug carried microspheres and swelling controlled release system are foreseen.
Delayed-Action Preparations ; Drug Carriers ; Drug Delivery Systems ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; Plants, Medicinal ; chemistry ; Polyvinyl Alcohol