scholarly journals Evaluation of the Adsorption and Desorption Dynamics of Beet Juice Red Dye on Alginate Microbeads

Gels ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 13
Author(s):  
Anamaria Birkić ◽  
Davor Valinger ◽  
Ana Jurinjak Jurinjak Tušek ◽  
Tamara Jurina ◽  
Jasenka Gajdoš Gajdoš Kljusurić ◽  
...  
Keyword(s):  
Food Industry ◽  
Diffusion Mechanism ◽  
Fickian Diffusion ◽  
Wall Material ◽  
Order Kinetic ◽  
Kinetic Rate Constant ◽  
Desorption Process ◽  
Adsorption And Desorption ◽  
Alginate Concentration ◽  
Red Dye

The use of alginate microcapsules has often been mentioned as one of the ways to remove dyes from waste solvents, water and materials from the food industry. In addition, alginate can be used as a wall material for the microencapsulation of food dyes and their further application in the food industry. The aims of this study were to: (i) determine the effect of the alginate concentration (1, 2, 3 and 4%) on the ability of the adsorption and desorption of natural beetroot red dye and (ii) evaluate the kinetic parameters of the adsorption and desorption process, as well as the factors affecting and limiting those processes. According to the obtained results, the viscosity of alginate solutions increased with an increase in the alginate concentration. Based on k2 values (the pseudo-second order kinetic rate constant), when a more concentrated solution of alginate was used in the adsorption process, the beads adsorbed a smaller amount of dye. Furthermore, based on the values for n derived from the Korsmeyer–Peppas model, the dye release rates (k) were higher for beads made with lower alginate concentrations, and this release was governed by a pseudo-Fickian diffusion mechanism (n values ranged from 0.2709 to 0.3053).

scholarly journals Synthesis of a Novel and Salt Sensitive Superabsorbent Hydrogel Using Soybean Dregs by UV-Irradiation

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2198 ◽  
Author(s):  
Yisa Fan ◽  
Mingyue Zhang ◽  
Linjian Shangguan
Keyword(s):  
Aqueous Solution ◽  
Water Retention ◽  
Agricultural Waste ◽  
Diffusion Mechanism ◽  
Fickian Diffusion ◽  
Distilled Water ◽  
Order Kinetic ◽  
Superabsorbent Hydrogel ◽  
Order Kinetic Model ◽  
Pseudo Second Order

A biomass based hydrogel soybean dregs-Poly(acrylic acid) (SD-PAA) was synthesized under UV radiation while using agricultural waste soybean dregs. Maximum absorption of SD-PAA is 3587 g·g−1 in distilled water and 302.0 g·g−1 in 150 mM NaCl aqueous solution. Moreover, the influence of granularity, salt solution, and ions in the solutions on water absorption is systematically studied. Sensitivity sequence of the hydrogel to cations was K+ < Na+ < NH4+ < Al3+ < Fe3+ < Mg2+ < Ca2+, and that to anions was PO43− > SO42− > Cl−. Moreover, the experimental results showed that SD-PAA water retention capability remained 37% after centrifugating for 60 min and 0.2% being dried at 60 °C for 70 h. Meanwhile, the swelling data agree well with the pseudo-second-order kinetic model and Fickian diffusion mechanism.

Development and Evaluation of Controlled Release Mucoadhesive Tablets of Captopril

1970 ◽  
Vol 9 (3) ◽  
pp. 3318-3329
Author(s):  
Kranthi Kumar Kotta ◽  
L. Srinivas
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Xanthan Gum ◽  
Diffusion Mechanism ◽  
Matrix Tablets ◽  
Fickian Diffusion ◽  
Content Uniformity ◽  
In Vitro Drug Release ◽  
Mucoadhesive Tablets

The present investigation focuses on the development of mucoadhesive tablets of captopril which are designed to prolong the gastric residence time after oral administration. Matrix tablets of captopril were formulated using four mucoadhesive polymers namely guar gum, xanthan gum, HPMC K4M and HPMC K15M and studied for parameters such as weight variation, thickness, hardness, content uniformity, swelling index, mucoadhesive force and in vitro drug release. Tablets formulated Xanthan gum or HPMC K4M with HPMC K15M provide slow release of captopril over period of 12 hr and were found suitable for maintenance portion of oral controlled release tablets. The cumulative % of drug release of formulation F9 and F10 were 90 and 92, respectively. In vitro release from these tablets was diffusion controlled and followed zero order kinetics. The ‘n’ values obtained from the pappas-karsemeyer equation suggested that all the formulation showed drug release by non-fickian diffusion mechanism. Tablets formulated Xanthan gum or HPMC K4M with HPMC K15M (1:1) were established to be the optimum formulation with optimum bioadhesive force, swelling index & desired invitro drug release. This product was further subjected to stability study, the results of which indicated no significant change with respect to Adhesive strength and in vitro drug release study.

scholarly journals Electrospun Janus Beads-On-A-String Structures for Different Types of Controlled Release Profiles of Double Drugs

Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 635
Author(s):  
Ding Li ◽  
Menglong Wang ◽  
Wen-Liang Song ◽  
Deng-Guang Yu ◽  
Sim Wan Annie Bligh
Keyword(s):  
Controlled Release ◽  
Combined Therapy ◽  
Diffusion Mechanism ◽  
Amorphous State ◽  
Electrospinning Process ◽  
Fickian Diffusion ◽  
In Vitro Dissolution ◽  
Sem Images ◽  
Release Profiles

A side-by-side electrospinning process characterized by a home-made eccentric spinneret was established to produce the Janus beads-on-a-string products. In this study, ketoprofen (KET) and methylene blue (MB) were used as model drugs, which loaded in Janus beads-on-a-string products, in which polyvinylpyrrolidone K90 (PVP K90) and ethyl cellulose (EC) were exploited as the polymer matrices. From SEM images, distinct nanofibers and microparticles in the Janus beads-on-a-string structures could be observed clearly. X-ray diffraction demonstrated that all crystalline drugs loaded in Janus beads-on-a-string products were transferred into the amorphous state. ATR-FTIR revealed that the components of prepared Janus nanostructures were compatibility. In vitro dissolution tests showed that Janus beads-on-a-string products could provide typical double drugs controlled-release profiles, which provided a faster immediate release of MB and a slower sustained release of KET than the electrospun Janus nanofibers. Drug releases from the Janus beads-on-a-string products were controlled through a combination of erosion mechanism (linear MB-PVP sides) and a typical Fickian diffusion mechanism (bead KET-EC sides). This work developed a brand-new approach for the preparation of the Janus beads-on-a-string nanostructures using side-by-side electrospinning, and also provided a fresh idea for double drugs controlled release and the potential combined therapy.

SUSTAINED RELEASE MATRIX TABLETS OF DICLOFENAC SODIUM EMPLOYING KOLLIDON SR, PEG 6000, LACTOSE MONO HYDRATE AND EUDRAGIT S100 IN COLON TARGET

INDIAN DRUGS ◽  
2017 ◽  
Vol 54 (10) ◽  
pp. 38-43
Author(s):  
Ch. Taraka Ramarao ◽  
◽  
B. Srinivasa Rao ◽  
J. Vijayaratana
Keyword(s):  
Drug Release ◽  
Diffusion Mechanism ◽  
Diclofenac Sodium ◽  
Zero Order ◽  
Matrix Tablets ◽  
Fickian Diffusion ◽  
Colon Targeting ◽  
Zero Order Kinetics ◽  
Eudragit S100 ◽  
Lag Period

Matrix Tablets, each containing 50 mg of diclofenac sodium, are prepared employing Kollidon SR by direct compression method. All the tablets were found to be non-disintegrating in acidic (pH1.2) and alkaline (pH 7.4) fluids. As such, the prepared tablets were of good quality with respect to drug content, hardness and friability. As the tablets formulated were non- disintegrating in acidic fluids, they are considered suitable for colon targeting. From the drug release study, it may be concluded that the (DK2) E2 formula of diclofenac sodium matrix tablets gives the desired release profile by showing a minimal release during the lag period of 5 h and complete release at the end of 12 h. The tablets having the optimised formula (DK2)E2, having 25% Kollidon SR with 5% of channelling agent (Eudragit S100 to that of Kollidon SR) showed minimal release of 27. 4% in the lag period of 5 hours and 99.3 % of the drug was released y the end of 12 h. The diclofenac sodium matrix tablets formulated by employing Kollidon SR and various channelling agents showed non-Fickian diffusion mechanism and followed zero order kinetics. The optimized formula (DK2) E2 follows Supercase II transport as mechanism for drug release and it follows zero order kinetics. Matrix tablets (DK2) E2 formulated employing 25% Kollidon SR and 5% Eudragit S100 are best suited to be used for colon targeting of diclofenac sodium.

Modeling of the Adsorption/Desorption Characteristics and Properties of Anthocyanins from Extruded Red Cabbage Juice by Macroporous Adsorbent Resin

2019 ◽  
Vol 15 (1-2) ◽  
Author(s):  
Pingjing Zhang ◽  
Liping Wang ◽  
Sheng Fang
Keyword(s):  
Adsorption Process ◽  
Fixed Bed ◽  
Order Kinetic ◽  
Adsorption And Desorption ◽  
Red Cabbage ◽  
Macroporous Resins ◽  
Freeze Dried ◽  
Order Kinetic Model ◽  
Color Density ◽  
Adsorption Desorption

AbstractThe adsorption/desorption characteristics, modeling and properties of anthocyanins from extruded red cabbage juice by macroporous resins were investigated. The static adsorption and desorption capacities of red cabbage anthocyanins on five macroporous resins were measured and compared. The X-5 resin showed the best capacities and was selected for the adsorption kinetics, isotherms and elution studies. The pseudo-second-order kinetic model and Langmuir isotherm model were used to describe the adsorption process and mechanism. Dynamic adsorption and desorption tests were performed on a fixed-bed column, and the loading and eluent conditions were optimized. The purity of anthocyanins in freeze-dried purified powder by the resin adsorption process is 21.3 ± 0.9 wt % and shows better stability in the air than the unpurified one. Finally, the antioxidant activity and color properties including color density, color intensity, color tonality and degradation index of the purified powders were measured.

scholarly journals Phenol Red Adsorption from Aqueous Solution on the Modified Bentonite

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Nguyen Le My Linh ◽  
Tran Duong ◽  
Hoang Van Duc ◽  
Nguyen Thi Anh Thu ◽  
Pham Khac Lieu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Cetyltrimethylammonium Bromide ◽  
Nitrogen Adsorption ◽  
Isotherm Models ◽  
Phenol Red ◽  
Order Kinetic ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Red Dye ◽  
Adsorption Desorption

In the present work, the modified bentonites were prepared by the modification of bentonite with cetyltrimethylammonium bromide (CTAB), both cetyltrimethylammonium bromide and hydroxy-Fe cations and both cetyltrimethylammonium bromide and hydroxy-Al cations. X-ray diffraction (XRD), thermal analysis (TG-DTA), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and nitrogen adsorption/desorption isotherms were utilized to characterize the resultant modified bentonites. The modified bentonites were employed for the removal of phenol red dye from aqueous solution. Phenol red adsorption agreed well with the pseudo-second-order kinetic model. The equilibrium data were analyzed on the basis of various adsorption isotherm models, namely, Langmuir, Freundlich, and Dubinin‒Radushkevich models. The highest monolayer adsorption capacity of phenol red at 30°C derived from the Langmuir equation was 166.7 mg·g−1, 125.0 mg·g−1, and 100.0 mg·g−1 for CTAB‒bentonite, Al‒CTAB‒bentonite, and Fe‒CTAB‒bentonite, respectively. Different thermodynamic parameters were calculated, and it was concluded that the adsorption was spontaneous (∆G° < 0) and endothermic (∆H° > 0), with increased entropy (∆S° > 0) in all the investigated temperature ranges.

Pyrite cinder as a cost-effective heterogeneous catalyst in heterogeneous Fenton reaction: decomposition of H2O2 and degradation of Acid Red B

2014 ◽  
Vol 70 (9) ◽  
pp. 1548-1554 ◽  
Author(s):  
Deli Wu ◽  
Yanxia Liu ◽  
Dong Duan ◽  
Luming Ma
Keyword(s):  
Catalytic Activity ◽  
Metal Ions ◽  
Cost Effective ◽  
High Catalytic Activity ◽  
Order Kinetic ◽  
Pyrite Cinder ◽  
Heterogeneous Fenton ◽  
Kinetic Rate Constant ◽  
Heterogeneous Fenton Reaction ◽  
Decomposition Of H2o2

Pyrite cinder (PyC) was employed as a heterogeneous Fenton-like catalyst, and its catalytic activity was evaluated in view of the effects of catalyst dosage, pH and leaching metal ions. PyC showed significant reactivity, and the pseudo-first-order kinetic rate constant for decomposition of H2O2 and degradation of Acid Red B (ARB) were 3.4 and 14.89 (10−3 min−1) respectively when pH = 5. When 20 g/L PyC was added into 10 mM H2O2 solution in neutral pH, H2O2 could be completely degraded within 4 h, and more than 90% ARB was removed. Leaching metal ions from PyC were found to have little effect on decomposition of H2O2 or on degradation of ARB. PyC still had high catalytic activity after five successive runs. The decomposition mechanism of H2O2 was analyzed and the Haber–Weiss mechanism was employed in this paper. The electron spin resonance image showed •OH was produced and increased between 3 and 5 min in the PyC catalyzing H2O2 reaction, which demonstrated that PyC had a durable ability to produce •OH.

scholarly journals Lignin reinforcement of urea-crosslinked starch films for reduction of starch biodegradability to improve slow nitrogen release properties under natural aerobic soil condition

e-Polymers ◽  
2016 ◽  
Vol 16 (2) ◽  
pp. 159-170 ◽  
Author(s):  
Zahid Majeed ◽  
Nurlidia Mansor ◽  
Zakaria Man ◽  
Samsuri Abd Wahid
Keyword(s):  
Diffusion Mechanism ◽  
Composite Films ◽  
Soil Condition ◽  
Reaction Rates ◽  
Order Reaction ◽  
Fickian Diffusion ◽  
Major Drawback ◽  
Study Results ◽  
Zero Order Reaction ◽  
Aerobic Soil

AbstractThe urea-crosslinked starch (UcS) film has a major drawback of very rapid biodegradability when applied as slow release fertilizer in soil. Lignin reinforcement of the UcS was used to prepare composite films, aimed to reduce the starch biodegradability and slow the release of nitrogen in aerobic soil condition. Study results revealed that mineralization of the composite films was delayed from 6.40 to 13.58% more than UcS film. Inhibition of composite films mixing with soil, the Michaelis-Menten reaction rates for α-amylase were inhibited ~1.72–2.03 times whereas the Michaelis-Menten reaction rates for manganese peroxidase were increased ~1.07–1.41 times compared to UcS film. Saccharides–glucose, maltose and maltotriose demonstrated that their rates of formation (zero-order reaction) and depletion (first-order reaction); both were slowed more in aerobic soil which received the composite films. Increasing of lignin in composite films, the acid to aldehyde ratios of vanillyl and syringyl phenols of the lignin declined from 1.18 to 1.17 (~0.76%) and 1.59–1.56 (~1.78%), respectively. The diffusivity of nitrogen was effectively slowed 0.66–0.94 times by the lignin in composite films and showed a “Fickian diffusion” mechanism (release exponent n=0.095–0.143).

Swelling Kinetic Study of Poly(Vinyl Alcohol)/Poly(γ-Glutamic Acid) Blend Hydrogel

2015 ◽  
Vol 1095 ◽  
pp. 423-426
Author(s):  
Mian Mian Zhang ◽  
Yu Xi Chen ◽  
Xia Ma
Keyword(s):  
Glutamic Acid ◽  
Kinetic Study ◽  
Vinyl Alcohol ◽  
Diffusion Mechanism ◽  
Fickian Diffusion ◽  
Poly Vinyl Alcohol ◽  
Swelling Kinetics ◽  
Swelling Mechanism ◽  
Swelling Kinetic ◽  
Sensitive Property

In this article, the swelling behavior and swelling kinetic of poly (vinyl alcohol)/poly (γ-glutamic acid) hydrogel were investigated. It was found that the PGA/PVA hydrogels revealed the pH-sensitive property and exhibited a faster swelling at pH7.4. The study of swelling kinetics revealed that the swelling mechanism followed the non-Fickian diffusion mechanism.

Sign in / Sign up

Export Citation Format

Share Document