Effects of molecular weight on macropore sizes and characterization of porous hydroxyapatite ceramics fabricated using polyethylene glycol: mechanisms to generate macropores and tune their sizes

Hybrids of hydroxyapatite (HAp) and poly(L-lactic co glycolic) (PLGA) have been fabricated, which can be expected to be a novel ﬁller for bone grafting. The porous HAp ceramics with bimodal pore structure have been fabricated from apatite fibers synthesized by homogeneous precipitation method. Then, HAp/PLGA hybrids have been fabricated by introducing PLGA having high molecular-weight into the open pores of the porous HAp ceramics. Total porosities of the porous HAp ceramics slightly decreased from 71.5% down to 67.4% after infiltrating PLGA into the porous HAp ceramics. The bending strength of the HAp/PLGA hybrids was ~ 8.3 MPa. The value attained about 2 times that of the porous HAp ceramics.

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Synthesis and Characterization of 5-Fluorouracil and Polyethylene Glycol Esters as Prodrugs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.1509 ◽

2011 ◽

Vol 287-290 ◽

pp. 1509-1512 ◽

Cited By ~ 1

Author(s):

Cheng Wu Li ◽

Gang Li ◽

Ji Cheng Zuo

Keyword(s):

Molecular Weight ◽

Polyethylene Glycol ◽

Water Solubility ◽

Uv Spectroscopy ◽

Chloroacetic Acid ◽

Synthesis And Characterization ◽

Drug Release Rate ◽

H Nmr ◽

Ft Ir

A series of novel polyethylene glycol derivates was synthesized by esterification of chloroacetic acid with polyethylene glycol.The PEG-5-FU conjugates were characterized by FT-IR,1H-NMR and UV spectroscopy. The result showed that 5-FU was successfully connected to the ends of PEG ester. Drug content of PEG2000-5-FU conjugate achieved 17.4%. As the molecular weight of PEG increased, the water solubility of prodrugs improved. When the molecular weight of PEG reached 2000, the conjugate had the best water solubility and the highest drug release rate.

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Synthesis and Characterization of Lignin-Based Polyurethane as a Potential Compatibilizer

Indonesian Journal of Chemistry ◽

10.22146/ijc.27176 ◽

2018 ◽

Vol 18 (3) ◽

pp. 390 ◽

Cited By ~ 4

Author(s):

Salma Ilmiati ◽

Jana Hafiza ◽

Jaka Fajar Fatriansyah ◽

Elvi Kustiyah ◽

Mochamad Chalid

Keyword(s):

Molecular Weight ◽

Surface Tension ◽

Thermal Properties ◽

Polyethylene Glycol ◽

Thermal Degradation ◽

Molar Mass ◽

Sessile Drop ◽

Synthesis And Characterization ◽

Hyperbranched Structure

Lignin is one of the most abundant biopolymer on earth. It has polar and non-polar side due to its hyperbranched structure, but the polarity of lignin has a higher tendency than non-polarity. Lignin has potential to be compatibilizer if the portion of non-polar can be increased. This research is focused on investigate the synthesis of lignin-based polyurethane to enhance the portion of non-polarity in lignin. Lignin-based polyurethane was prepared by reacting variation 4,4'-Methylenebis(cyclohexyl isocyanate) (HMDI) and polyethylene glycol (PEG), then lignin was added to the reaction. In this study, the structure of lignin-based polyurethane was confirmed by NMR and FTIR. NMR and FTIR showed that lignin successfully grafted. NMR, also used to investigate the variation molar mass of PEG and isocyanate contents effects to polarity of lignin-based polyurethane. The polarity of lignin-based polyurethane decrease as the composition of HMDI and molecular weight of PEG increase. This result also occurs on the sessile drop test that used to determine surface tension of lignin-based polyurethane. The thermal properties of lignin-based polyurethane also investigate using STA. Based on STA, enhancement of composition of HMDI and PEG increase thermal degradation and resistance of lignin-based polyurethane.

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Isolation and Characterization of Plasminogen Activator from Pig Leucocytes

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649147 ◽

1974 ◽

Vol 31 (01) ◽

pp. 072-085 ◽

Cited By ~ 5

Author(s):

M Kopitar ◽

M Stegnar ◽

B Accetto ◽

D Lebez

Keyword(s):

Molecular Weight ◽

Plasminogen Activator ◽

Gel Electrophoresis ◽

Gel Filtration ◽

Ph Optimum ◽

Isolation And Characterization ◽

Ph Range ◽

Inhibition Studies ◽

Final Purification

SummaryPlasminogen activator was isolated from disrupted pig leucocytes by the aid of DEAE chromatography, gel filtration on Sephadex G-100 and final purification on CM cellulose, or by preparative gel electrophoresis.Isolated plasminogen activator corresponds No. 3 band of the starting sample of leucocyte cells (that is composed from 10 gel electrophoretic bands).pH optimum was found to be in pH range 8.0–8.5 and the highest pH stability is between pH range 5.0–8.0.Inhibition studies of isolated plasminogen activator were performed with EACA, AMCHA, PAMBA and Trasylol, using Anson and Astrup method. By Astrup method 100% inhibition was found with EACA and Trasylol and 30% with AMCHA. PAMBA gave 60% inhibition already at concentration 10–3 M/ml. Molecular weight of plasminogen activator was determined by gel filtration on Sephadex G-100. The value obtained from 4 different samples was found to be 28000–30500.

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Studies on the Characterization of Factor VIII and a Co-factor VIII

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649167 ◽

1974 ◽

Vol 31 (02) ◽

pp. 328-338

Author(s):

M. M. P Paulssen ◽

H. L. M. A Vandenbussche-Scheffers ◽

P. B Spaan ◽

T de Jong ◽

M. C Planje

Keyword(s):

Molecular Weight ◽

Factor Viii ◽

The Body ◽

Haemophilia A ◽

Von Willebrand's Disease ◽

Von Willebrand’S Disease ◽

Polysaccharide Content ◽

Plasma Factor ◽

Two Factors

SummaryFactor VIII occurs in the body in two different forms. In lymph factor VIII is bound to chylomicra. In plasma, factor VIII is bound to a protein.After delipidation of chylomicra we obtained a glycoprotein with a high polysaccharide content and a molecular weight of approx. 160,000.In plasma, factor VIII is attached to a protein which is present in normal concentrations in plasma of patients with haemophilia A and in serum (co-factor VIII).This factor is deficient in both the plasma and the serum of patients with von Willebrand’s disease.The binding between factor VIII and co-factor VIII is reversible.Some properties of these two factors are described.

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Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657167 ◽

1982 ◽

Vol 47 (03) ◽

pp. 197-202 ◽

Cited By ~ 23

Author(s):

Kurt Huber ◽

Johannes Kirchheimer ◽

Bernd R Binder

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Human Urine ◽

Gel Filtration ◽

Chain Structure ◽

The Other ◽

Single Chain ◽

Apparent Homogeneity ◽

Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

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Prothrombin Metz : Purification and Characterization of a Variant of Human Prothrombin

10.1055/s-0038-1665670 ◽

1979 ◽

Author(s):

M Ribieto ◽

J Elion ◽

D Labie ◽

F Josso

Keyword(s):

Molecular Weight ◽

Gel Electrophoresis ◽

Polyacrylamide Gel Electrophoresis ◽

Factor Xa ◽

Polyacrylamide Gel ◽

Cleavage Pattern ◽

Purification And Characterization ◽

Double Immunodiffusion ◽

The Family

For the purification of the abnormal prothrombin (Pt Metz), advantage has been taken of the existence in the family of three siblings who, being double heterozygotes for Pt Metz and a hypoprothrombinemia, have no normal Pt. Purification procedures included barium citrate adsorption and chromatography on DEAE Sephadex as for normal Pt. As opposed to some other variants (Pt Barcelona and Madrid), Pt Metz elutes as a single symetrical peak. By SDS polyacrylamide gel electrophoresis, this material is homogeneous and appears to have the same molecular weight as normal Pt. Comigration of normal and abnormal Pt in the absence of SDS, shows a double band suggesting an abnormal charge for the variant. Pt Metz exhibits an identity reaction with the control by double immunodiffusion. Upon activation by factor Xa, Pt Metz can generate amydolytic activity on Bz-Phe-Val-Arg-pNa (S2160), but only a very low clotting activity. Clear abnormalities are observed in the cleavage pattern of Pt Metz when monitored by SDS gel electrophoresis. The main feature are the accumulation of prethrombin l (Pl) and the appearance of abnormal intermediates migrating faster than Pl.

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