scholarly journals STABILITY OF KETOPROFEN COATED BY CHITOSAN-GUAR GUM GEL

2010 ◽  
Vol 9 (3) ◽  
pp. 391-397
Author(s):  
Purwantiningsih Sugita ◽  
Bambang Srijanto ◽  
Budi Arifin ◽  
Ellin Vina Setyowati
Keyword(s):  
Room Temperature ◽  
Degradation Rate ◽  
Guar Gum ◽  
Reaction Kinetic ◽  
Tween 80 ◽  
Chitosan Solution ◽  
Climatic Chamber ◽  
Fine Powders ◽  
Magnetic Stirrer ◽  
Degradation Rate Constant

The coating stability of ketoprofen by chitosan-guar gum gel has been studied. Into 228.6 mL of 1.75% (w/v) chitosan solution in 1% (v/v) acetic acid, 38.1 mL of guar gum (gg) solution was added with concentration variation of 0.35, 0.55, and 0.75% (w/v) for ketoprofen microcapsules, and stirred with magnetic stirrer until homogenous. Afterwards, 7.62 mL of glutaraldehyde (glu) was added slowly under stirring, with concentrations varied: 3, 3.5, and 4% (v/v). All mixtures were shaked for 20 min for homogenization. Into each microcapsule mixture for ketoprofen, a solution of 2 g of ketoprofen in 250 mL of 96% ethanol was added. Every mixture was then added with 5 mL of 2% Tween-80 and stirred with magnetic stirrer for an hour at room temperature. Conversion of suspension into fine powders/granules (microcapsules) was done by using spray dryer. Every microcapsule formula was packed into capsules, as much as 100 g per capsule. The capsules were contained in 100-mL dark bottles and the bottles were kept in climatic chamber at (40 ± 2) °C and RH (75 ± 5) % for 3 months. The microcapsule stabilities were tested chemically and physically. The result showed that formulation of ketoprofen preparation composed of 1.75% (w/v) chitosan, 0.35% (w/v) gg, and 3.50% (v/v) glu, was relatively the best, with ketoprofen percentage left in microcapsule after 3 months, degradation rate constant, and shelf life of 80.33%, 0.0351 % week-1, and 18.92 months, respectively. Reaction kinetic model for this formula followed Prout-Tompkins equation and the degradation of ketoprofen was seem to follow autocatalytic reaction mechanism controlled by the formation and growth of reaction core.   Keywords: Ketoprofen, chitosan-guar gum gel

PERILAKU DISOLUSI KETOPROFEN DAN INDOMETASIN FARNESIL TERSALUT GEL KITOSAN-GOM GUAR

2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Purwantiningsih Sugita ◽  
Bambang Srijanto ◽  
Budi Arifin ◽  
Fithri Amelia ◽  
Mahdi Mubarok
Keyword(s):  
Room Temperature ◽  
Guar Gum ◽  
Tween 80 ◽  
Chitosan Solution ◽  
In Vitro Dissolution ◽  
Dissolution Profile ◽  
Magnetic Stirrer ◽  
Dissolution Behaviour ◽  
Shrimp Shell Waste

Chitosan, a modification of shrimp-shell waste, has been utilized as microcapsule. However, it’s fragile gel property needs to be strengthened by adding glutaraldehyde (glu) and natural hydrocolloid guar gum (gg). This research’s purposes were to study dissolution behaviour of ketoprofen and infar through optimum chitosan-guar gum microcapsule. Into 228.6 mL of 1.75% (w/v) chitosan solution in 1% (v/v) acetic acid,38.1 mL of gg solution was added with concentration variation of 0.35, 0.55, and 0.75% (w/v) for ketoprofen microcapsules and 0.05, 0.19, and 0.33% (w/v) for infar microcapsules, and stirred with magnetic stirrer until homogenous. Afterwards, 7.62mL of glu was added slowly under stirring, with concentrations varied: 3, 3.5, and 4% (v/v) for ketoprofen microcapsules, and 4, 4.5, and 5% (v/v) for infar microcapsules. All mixtures were shaked for 20 minutes for homogenization. All mixtures wereshaked for 20 minutes for homogenization. Into each  microcapsule mixture for ketoprofen, a solution of 2 g of ketoprofen in 250 mL of 96% ethanol was added, whereas solution of 100 mg of in 250 mL of 96% ethanol was added into each microcapsule mixture for infar. Every mixture was then added with 5 mL of 2% Tween-80 and stirred with magnetic stirrer for an hour at room temperature. Everymixture was then added with 5 mL of 2% Tween-80 and stirred with magnetic stirrer for an hour at room temperature. Conversion of suspension into fine powders/granules (microcapsules) was done by using spray dryer. The data of [gg], [glu], and medicine’s content from each microcapsule were treated with Minitab 14 software to obtain optimum [gg] and [glu] for microencapsulation. The dissolution behaviour of optimum ketoprofen and infar microcapsules were investigated. The result of optimization by using Minitab Release 14 software showed that among the microcapsule compositions of [gg] and [glu] were 0.35% (w/v) and 3.75% (v/v), respectively, optimum to coat ketoprofen, whereas [gg] and [glu] of 0.05% (w/v) and4.00% (v/v), respectively, optimum to coat infar, at constant chitosan concentration (1.75% [w/v]). In vitro dissolution profile showed that chitosan-guar gum gel microcapsule was more resistant in intestinal pH condition (rather basic) compared with that in gastric pH (very acidic).

Effect of Cellulase Enzymes on Degradation Characteristics of Ensiled Rice Straw

1988 ◽  
Vol 1988 ◽  
pp. 83-83
Author(s):  
Y. Nakashima ◽  
E.R. Ørskov ◽  
K. Ambo ◽  
Y. Takase
Keyword(s):  
Rice Straw ◽  
Dry Matter ◽  
Room Temperature ◽  
Degradation Rate ◽  
Enzyme Preparation ◽  
Lower Content ◽  
Cellulase Enzymes ◽  
Cellulase Enzyme ◽  
Physical Form ◽  
Degradation Rate Constant

AbstractRice straw was ensiled in laboratory containers of 11 capacity. Three concentrations of moisture (50, 60 or 70%) 3 concentrations of a commercial cellulase enzyme preparation (0, 5 or 10g/kg dry matter (DM)) and 3 types of straw processing (2 cm, 5 mm or 2 mm length) were used. The preparations were stored at room temperature (approximately 20°C) for 30 days. The straw treated with cellulase had a lower final pH (5.21, 4.87, 4.82; P<0.05), higher concentrations of lactic acid (198, 383, 367 mg/100g; P<0.05), a lower content of neutral detergent fibre (689, 630, 620 g/kg DM; P<0.05) and a higher solubility, measured as washing losses from nylon bags (152, 196, 212 g/kg DM; P<0.05) for the 0, 5 and 10 g/kg cellulase treatments respectively. The samples were subsequently incubated in nylon bags in the rumen of 3 sheep for 8, 16, 24, 48 and 72 h to estimate degradation rate and potential degradability using the expression p+a+b(1-e-ct) where p is degradability at time t and a, b and c are constants. While there was no effect of moisture content or physical form of the straw, the degradation rate constant (c) was significantly increased (P<0.05) by the addition of cellulase. The maximum potential (a+b) however was unchanged. The values for c were 0.0496, 0.0677 and 0.0847/h-1 and the values for (a+b) were 624, 621 and 628 g/kg for the 0, 5 and 10 g/kg cellulase enzyme additions respectively. It is concluded that the use of cellulase enzymes can assist in the preservation of wet straw and can result in improved degradation characteristics.

scholarly journals Perilaku Disolusi Ketoprofen Tersalut Gel Kitosan-Karboksimetilselulosa (CMC)

2012 ◽  
Vol 13 (1) ◽  
pp. 21
Author(s):  
Purwantiningsih Sugita ◽  
Suminar Setiati Achmadi ◽  
Yuyu Yundhana
Keyword(s):  
Guar Gum ◽  
Tween 80 ◽  
Chitosan Solution ◽  
In Vitro Dissolution ◽  
Dissolution Profile ◽  
Drying Process ◽  
Dissolution Behaviour ◽  
Before And After ◽  
Sem Morphology

Study dissolution behaviour of ketoprofen through optimum chitosan-CMC microcapsule has been carried out. Into228.6 ml of 1.0% (w/v) chitosan solution in 1% (v/v) acetic acid, 38.1 ml of CMC solution was added with concentrationvariation of 0.075; 0.0875; and 0.10% (w/v). Afterwards, 7.62 mL of glu was added slowly under stirring, withconcentrations varied: 3; 4.5; and 6% (v/v). All mixtures were shaked for 20 minutes for homogenization. Into eachmicrocapsule mixture for ketoprofen, a solution of 2 g of ketoprofen in 250 mL of 96% ethanol was added. Everymixture was then added with 5 ml of 2% Tween-80 and stirred with magnetic stirrer for an hour at room temperature.Conversion of suspension into fine powders/granules (microcapsules) was done by using spray dryer. Thedissolution behaviour of optimum ketoprofen microcapsules were investigated in gastric and intestinal medium.Microcapsule morphology before and after dissolution as well as empty microcapsule (blank) were observed withSEM. Spray drying process had successfully coated ketoprofen in chitosan-CMC microcapsule. Optimization byusing Minitab Release 14 software showed that among the microcapsule compositions studied, CMC and glu of0.0925% (w/v) and 3.01% (v/v), respectively, optimum to coat ketoprofen at constant chitosan concentration 1.0%(w/v). Result of SEM morphology and In vitro dissolution profile showed that ketoprofen in chitosan-CMCmicrocapsule was relatively well than chitosan-guar gum microcapsule. Kinetically, dissolution of ketoprofen frommicrocapsule in intestinal pH condition was first order with release rate constant, k, of 7.285  10-4 % min-1 andrelease half-time, t1/2, of approximately 15 hours.

scholarly journals Long term conservation of DNA at ambient temperature. Implications for DNA data storage

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259868
Author(s):  
Delphine Coudy ◽  
Marthe Colotte ◽  
Aurélie Luis ◽  
Sophie Tuffet ◽  
Jacques Bonnet
Keyword(s):  
Data Storage ◽  
Room Temperature ◽  
Degradation Rate ◽  
White Blood Cells ◽  
High Capacity ◽  
Precise Determination ◽  
Buffy Coat ◽  
Degradation Rate Constant

DNA conservation is central to many applications. This leads to an ever-increasing number of samples which are more and more difficult and costly to store or transport. A way to alleviate this problem is to develop procedures for storing samples at room temperature while maintaining their stability. A variety of commercial systems have been proposed but they fail to completely protect DNA from deleterious factors, mainly water. On the other side, Imagene company has developed a procedure for long-term conservation of biospecimen at room temperature based on the confinement of the samples under an anhydrous and anoxic atmosphere maintained inside hermetic capsules. The procedure has been validated by us and others for purified RNA, and for DNA in buffy coat or white blood cells lysates, but a precise determination of purified DNA stability is still lacking. We used the Arrhenius law to determine the DNA degradation rate at room temperature. We found that extrapolation to 25°C gave a degradation rate constant equivalent to about 1 cut/century/100 000 nucleotides, a stability several orders of magnitude larger than the current commercialized processes. Such a stability is fundamental for many applications such as the preservation of very large DNA molecules (particularly interesting in the context of genome sequencing) or oligonucleotides for DNA data storage. Capsules are also well suited for this latter application because of their high capacity. One can calculate that the 64 zettabytes of data produced in 2020 could be stored, standalone, for centuries, in about 20 kg of capsules.

scholarly journals Long term conservation of DNA at ambient temperature. Implications for DNA data storage

2021 ◽  
Author(s):  
Delphine Coudy ◽  
Marthe Colotte ◽  
Aurelie Luis ◽  
Sophie Tuffet ◽  
Jacques Bonnet
Keyword(s):  
Data Storage ◽  
Room Temperature ◽  
Degradation Rate ◽  
White Blood Cells ◽  
High Capacity ◽  
Precise Determination ◽  
Buffy Coat ◽  
Degradation Rate Constant

DNA conservation is central to many applications. This leads to an ever-increasing number of samples which are more and more difficult and costly to store or transport. A way to alleviate this problem is to develop procedures for storing samples at room temperature while maintaining their stability. A variety of commercial systems have been proposed but they fail to completely protect DNA from deleterious factors, mainly water. On the other side, Imagene company has developed a procedure for long-term conservation of biospecimen at room temperature based on the confinement of the samples under an anhydrous and anoxic atmosphere maintained inside hermetic capsules. The procedure has been validated by us and others for purified RNA, and DNA in buffy coat or white blood cells lysates, but a precise determination of purified DNA stability is still lacking. We used the Arrhenius law to determine the DNA degradation rate at room temperature. We found that extrapolation to 25 degree C gave a degradation rate constant equivalent to about 1 cut per century per 100000 nucleotides, a stability several orders of magnitude larger than the current commercialized processes. Such a stability is fundamental for many applications such as the preservation of very large DNA molecules (particularly interesting in the context of genome sequencing) or oligonucleotides for DNA data storage. Capsules are also well suited for this latter application because of their high capacity. One can calculate that the 64 zettabytes of data produced in 2020 could be stored, standalone, for centuries, in about 20 kg of capsules.

scholarly journals A Facile and Efficient Bromination of Multi-Walled Carbon Nanotubes

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3161
Author(s):  
Sandra Zarska ◽  
Damian Kulawik ◽  
Volodymyr Pavlyuk ◽  
Piotr Tomasik ◽  
Alicja Bachmatiuk ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Room Temperature ◽  
Covalent Attachment ◽  
Closed Vessel ◽  
Dangling Bonds ◽  
Magnetic Stirrer ◽  
Defect Sites ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Covalently Bound

The bromination of multi-walled carbon nanotubes (MWCNT) was performed with vapor bromine in a closed vessel, and they were subjected to intensive stirring with a magnetic stirrer for up to 14 days. The efficiency of bromination was compared depending upon duration. The structure and surface of the crude and purified products were characterized by detailed physicochemical analyses, such as SEM/EDS, TEM, XRD, TGA, Raman, and XPS spectroscopies. The studies confirmed the presence of bromine covalently bound with nanotubes as well as the formation of inclusion MWCNT–Br2 complexes. It was confirmed that Br2 molecules are absorbed on the surface of nanotubes (forming the CNT-Br2 complex), while they can dissociate close to dangling bonds at CNT defect sites with the formation of covalent C−Br bonds. Thus, any covalent attachment of bromine to the graphitic surface achieved around room temperature is likely related to the defects in the MWCNTs. The best results, i.e., the highest amount of attached Br2, were obtained for brominated nanotubes brominated for 10 days, with the content of covalently bound bromine being 0.68 at% (by XPS).

scholarly journals Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 558
Author(s):  
Wenhui Zhu ◽  
Caiyun Zhang ◽  
Yali Chen ◽  
Qiliang Deng
Keyword(s):  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Degradation Rate ◽  
Model Compound ◽  
Vibrating Sample Magnetometer ◽  
Simulated Sunlight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

A bioprinted composite hydrogel with controlled shear stress on cells

2020 ◽  
pp. 095441192097668
Author(s):  
Amirhossein Bakhtiiari ◽  
Rezvan Khorshidi ◽  
Fatemeh Yazdian ◽  
Hamid Rashedi ◽  
Meisam Omidi
Keyword(s):  
Shear Stress ◽  
Cell Viability ◽  
Room Temperature ◽  
Degradation Rate ◽  
Diffusion Rate ◽  
Sol Gel ◽  
Three Dimensional ◽  
Simulation Software ◽  
Sol Gel Transition ◽  
Gel Transition

In recent decades, three dimensional (3D) bio-printing technology has found widespread use in tissue engineering applications. The aim of this study is to scrutinize different parameters of the bioprinter – with the help of simulation software – to print a hydrogel so much so that avoid high amounts of shear stress which is detrimental for cell viability and cell proliferation. Rheology analysis was done on several hydrogels composed of different percentages of components: alginate, collagen, and gelatin. The results have led to the combination of percentages collagen:alginate:gelatin (1:4:8)% as the best condition which makes sol-gel transition at room temperature possible. The results have shown the highest diffusion rate and cell viability for the cross-linked sample with 1.5% CaCl2 for the duration of 1 h. Finally, we have succeeded in printing the hydrogel that is mechanically strong with suitable degradation rate and cell viability.

Influence of Surfactants on Biodegradation of Chlordane by Wood-Rotting Fungus

2013 ◽  
Vol 361-363 ◽  
pp. 908-911
Author(s):  
Peng Fei Xiao ◽  
Tie Xue You ◽  
Yu Zhen Song ◽  
Shan Ying ◽  
Jian Qiao Wang
Keyword(s):  
Liquid Medium ◽  
Degradation Rate ◽  
Solid Medium ◽  
Fungal Growth ◽  
Tween 80 ◽  
Positive Effects ◽  
Lower Effect ◽  
Triton X

Wood-rotting fungus,Phlebia lindtneriGB 1027, was tested in toxicity assays with three surfactants in order to select surfactants for degradation assays of chlordane. Tween 80 and Triton X-100 appeared to have lower effect on the fungal growth on solid medium, while higher effect of fungal growth was observed in solid medium with SDS. Tween 80 had positive effects both on the chlordane degradation and the fungal growth. When fungus was incubated on PDB liquid medium with Tween 80 of 10 CMC after 20 d, 78.6% of chlordane was removed. In the treatments with Triton X-100, this strain showed comparatively greatest degradation rate (70.8%) of chlordane at a concentration of 2 CMC. However, when Triton X-100 concentration was higher than 2 CMC (5 and 10 CMC), the enhancement for the biodegradation of chlordane decreased.

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