scholarly journals Controlled Release of TBH Herbicide Encapsulated on Ca-ALG Microparticles: Leaching and Phytointoxication Plants

2019 ◽  
Vol 37 ◽  
Author(s):  
D.F. MACEDO ◽  
S.M. DOURADO JR. ◽  
E.S. NUNES ◽  
R.P. MARQUES ◽  
J.A. MORETO
Keyword(s):  
Aqueous Solution ◽  
Controlled Release ◽  
Soil Contamination ◽  
Sodium Alginate ◽  
Calcium Chloride ◽  
Calcium Alginate ◽  
Dry Mass ◽  
Leaching Process ◽  
The One

ABSTRACT: The aim of this work was to demonstrate a detailed study of the controlled release of the herbicide Tebuthiuron (TBH) encapsulated in microparticles of calcium alginate (Ca-ALG), to evaluate the phytotoxicity in different concentrations of herbicide (4, 6 and 8 g L-1), and their correlation with the depth of leaching using bioindicator plants. The Ca-ALG microparticles were prepared from the crosslinking of sodium alginate by Ca++ containing varied amounts of TBH supplied in calcium chloride (CaCl2) aqueous solution. The results showed that TBH herbicide, when encapsulated, leached to shallow depths relative to the conventional, non-encapsulated herbicide (which moved to a depth of 40-50 cm). The concentration of 4 g L-1 was the one that leached most in the PVC columns, but its mobility did not exceed 30 cm of depth. The results of the dry mass corroborated with the phytotoxicity results of the bioindicator plants, evidencing the mobility of the conventional herbicide in the soil at depths around 40 and 50 cm, while the herbicide encapsulated in the Ca-ALG microparticles did not show leaching beyond 20 -30 cm deep. The encapsulation of TBH in Ca-ALG microparticles can thus be considered as a more eco-friendly technology, reducing the leaching process and consequently soil contamination.

scholarly journals DESIGN AND EVALUATION OF CONTROLLED-RELEASE OCULAR INSERTS OF BRIMONIDINE-TARTRATE AND TIMOLOL MALEATE

2016 ◽  
Vol 9 (1) ◽  
pp. 79 ◽  
Author(s):  
Preethi G. B. ◽  
Prashanth Kunal
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Sodium Alginate ◽  
Calcium Chloride ◽  
Release Kinetics ◽  
Water Soluble ◽  
Moisture Loss ◽  
Timolol Maleate ◽  
Brimonidine Tartrate

<p><strong>Objective: </strong>The current work was attempted to formulate and evaluate a controlled-release matrix-type ocular inserts containing a combination of brimonidine tartrate and timolol maleate, with a view to sustain the drug release in the cul-de-sac of the eye.<strong></strong></p><p><strong>Methods: </strong>Initially, the infrared studies were done to determine the drug–polymer interactions. Sodium alginate-loaded ocuserts were prepared by solvent casting technique. Varying the concentrations of polymer—sodium alginate, plasticizer—glycerine, and cross-linking agent—calcium chloride by keeping the drug concentration constant, made a total of nine formulations. These formulations were evaluated for its appearance, drug content, weight uniformity, thickness uniformity, percentage moisture loss, percentage moisture absorption, and <em>in vitro </em>release profile of the ocuserts. Finally, accelerated stability studies and the release kinetics were performed on the optimised formulation.<strong></strong></p><p><strong>Results: </strong>It was perceived that polymer, plasticizer, and calcium chloride had a significant influence on the drug release. The data obtained from the formulations showed that formulation—F9 was the optimised formulation, which exhibited better drug release. The release data of the optimised formulation tested on the kinetic models revealed that it exhibited first-order release kinetics. <strong></strong></p><p><strong>Conclusion: </strong>It can be concluded that a natural bioadhesive hydrophilic polymer such as sodium alginate can be used as a film former to load water soluble and hydrophilic drugs like brimonidine tartrate and timolol maleate. Among all formulations, F9 with 400 mg sodium alginate, 2% calcium chloride and 60 mg glycerin were found to be the most suitable insert in terms of appearance, ease of handling, thickness, <em>in vitro</em> drug release and stability.</p>

scholarly journals MICROENCAPSULATION of grapefruit oil with sodium alginate by gelation and ionic extrusion: optimization and modeling of crosslinking and study of controlled release kinetics.

2020 ◽  
pp. 41-61
Author(s):  
Liliana Mariel Cáceres ◽  
Gustavo Adolfo Velasco ◽  
Eliana Paola Dagnino ◽  
Ester R Chamorro
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Calcium Chloride ◽  
Release Kinetics ◽  
Antimicrobial Properties ◽  
Chloride Concentration ◽  
Crosslinking Process ◽  
Elovich Equation ◽  
Pharmaceutical Industries ◽  
High Concentrations

Essential grapefruit oil with high concentrations of limonene is used in food, cosmetic and pharmaceutical industries due to its antimicrobial properties, fragrance, and flavor. To facilitate its manipulation and protect it from adverse environmental factors, the microencapsulation is used. The objective of this work was to optimize the microencapsulation process of grapefruit oil using external ionic gelation coupled to extrusion with sodium alginate and calcium chloride. We achieved the best encapsulation conditions with calcium chloride concentration at 7.4% w/v and a crosslinking time of 58 minutes, obtaining a yield of 62% and an efficiency of 100% with an oil loading capacity of 10% w/w. The chemical adsorption of calcium as well during the crosslinking process was studied, observing a significant fit with the Elovich equation. And an adjustment of the controlled release of the oil was obtained to the empirical kinetic model of Korsmeyer and Peppas.

scholarly journals Optimization of Immobilization Condition of Protease Extracted from Silver Catfish (Pangasius Sutchi) Viscera in Calcium Alginate by using Response Surface Methodology (RSM)

2021 ◽  
Vol 18 (1) ◽  
pp. 179
Author(s):  
Normah Ismail ◽  
Siti Noorsyarafana Sahimi
Keyword(s):  
Optimum Condition ◽  
Sodium Alginate ◽  
Calcium Chloride ◽  
Calcium Alginate ◽  
Chloride Solution ◽  
Alginate Beads ◽  
Calcium Chloride Solution ◽  
Silver Catfish ◽  
Significant Difference ◽  
Proteolytic Activities

The term of immobilized enzymes refers to enzymes that physically entrapped within pores of synthetic or natural polymeric network with no alteration in the enzyme catalytic activities. In this study, protease from silver catfish viscera have been extracted, partially purified by acetone precipitation method and immobilised in the calcium alginate beads. Various range of sodium alginate (1–5% w/v) and calcium chloride (0.1–0.5 M) concentrations were used for the optimization purpose. Proteolytic activity of the protease in the alginate beads was measured as a response to the independent variables by using casein as a substrate. The highest actual and predicted proteolytic activities were at run 12 with 674.77 CDU/mg and 639.26 CDU/mg, respectively, under predetermined factors, in which the sodium alginate and calcium chloride solution concentrations were at 3.00% (w/v) and 0.30 M, respectively. The lowest actual and predicted proteolytic activities were at run 2 with the values of 77.35 CDU/mg and 71.53 CDU/mg, respectively, whereby factors include were a sodium alginate of 4.00% (w/v) and 0.20 M of calcium chloride solution. For the experimental feasibilities, the optimum conditions that was feasible to be carried out was with a sodium alginate of 2.99% (w/v) and 0.30 M calcium chloride solution. Verification for the optimum condition was performed and there was no significant difference (p > 0.05) between the predicted (638.19 CDU/mg) and verified (699.82 CDU/mg) values. Thus, indicating that the model was significant and can be used to produce the immobilize protease under the optimum condition.

scholarly journals Alginate-pomegranate peels' polyphenols beads: effects of formulation parameters on loading efficiency

2014 ◽  
Vol 50 (4) ◽  
pp. 741-748 ◽  
Author(s):  
Wissam Zam ◽  
Ghada Bashour ◽  
Wassim Abdelwahed ◽  
Warid Khayata
Keyword(s):  
Sodium Alginate ◽  
Calcium Chloride ◽  
Calcium Alginate ◽  
Chloride Concentration ◽  
Natural Antioxidants ◽  
Alginate Beads ◽  
Food Supplementation ◽  
Calcium Alginate Beads ◽  
Loading Efficiency ◽  
Alginate Concentration

Calcium alginate beads containing pomegranate peels' polyphenol extract were encapsulated by ionic gelation method. The effects of various formulation factors (sodium alginate concentration, calcium chloride concentration, calcium chloride exposure time, gelling bath time maintaining, and extract concentration) on the efficiency of extract loading were investigated. The formulation containing an extract of 1 g pomegranate peels in 100 mL distilled water encapsulated with 3 % of sodium alginate cured in 0.05 M calcium chloride for 20 minutes and kept in a gelling bath for 15 minutes was chosen as the best formula regarding the loading efficiency. These optimized conditions allowed the encapsulation of 43.90% of total extracted polyphenols and 46.34 % of total extracted proanthocyanidins. Microencapsulation of pomegranate peels' extract in calcium alginate beads is a promising technique for pharmaceutical and food supplementation with natural antioxidants.

Understanding Release Kinetics of Calcium Alginate Microcapsules Using Drop on Demand Inkjet Printing

2009 ◽  
Author(s):  
Jessica L. Perkins ◽  
Salil Desai ◽  
Benjamin Harrison ◽  
Jagannathan Sankar
Keyword(s):  
Sodium Alginate ◽  
Calcium Chloride ◽  
Calcium Alginate ◽  
Rhodamine 6G ◽  
Release Kinetics ◽  
Release Behavior ◽  
On Demand ◽  
Drop On Demand ◽  
Kinetics Of ◽  
Rhodamine 6G Dye

This paper investigates the use of calcium alginate microcapsules to transport biomaterials for drug delivery. Rhodamine 6G dye was encapsulated in microcapsules for different formulations of the hydrogels using drop-on-demand printing. An experimental design was constructed to compare the effect of different concentrations of calcium chloride (M) and sodium alginate (% w/v) solutions in addition to the microcapsule diameter on the release kinetics profiles of the microcapsules. The results of these findings provide a basis to identify favorable sizes of microcapsules and concentrations of sodium alginate and calcium chloride solutions for controlled release behavior of microcapsules.

scholarly journals NOVEL PHARMACEUTICAL DOSAGE FORM

2018 ◽  
Vol 8 (5) ◽  
pp. 1-2
Author(s):  
A Padiyar ◽  
RK Maheshwari
Keyword(s):  
Sodium Alginate ◽  
Calcium Chloride ◽  
Calcium Alginate ◽  
Dosage Form ◽  
Dosage Forms ◽  
Pharmaceutical Dosage Form ◽  
Oral Liquid

Objective of the proposed idea is to introduce novel pharmaceutical dosage form prepared of biodegradable polymeric balls. These polymeric balls will encircle oral liquid dosage forms within an edible membrane which can be flavoured, coloured, and can be used as unit dosage form. It will be prepared by reaction between sodium alginate and calcium chloride resulting in spherical, flexible ball of calcium alginate. Current research will eliminate the use of plastics as syrups or other liquid dosage forms will be provided in these balls which will be more economic and eco-friendly. Keywords: novel pharmaceutical dosage, polymeric balls, sodium alginate, eco-friendly

Evaluation of Aceclofenac Loaded Alginate Mucoadhesive Spheres Prepared by Ionic Gelation

2013 ◽  
Vol 5 (4) ◽  
pp. 1847-1857
Author(s):  
M. Mohan Varma ◽  
H.L.N Rao
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Calcium Chloride ◽  
Zero Order ◽  
Fickian Diffusion ◽  
Content Uniformity ◽  
Drug Content ◽  
Mucoadhesive Property ◽  
Drug Polymer Interaction ◽  
Polymer Interaction

Controlled release aceclofenac spheres were prepared in a cross-linked alginate matrix using ionotropic gelation technique. A suspension of aceclofenac in sodium alginate solution was added drop wise into 10% w/v calcium chloride solution and the resulting spheres were evaluated for their drug content, flow properties, mucoadhesive property and the dissolution rate. The aceclofenac loaded alginate spheres were prepared using various mucoadhesive polymers: sodium alginate, HPMC, sodium CMC, guar gum, methyl cellulose and carbopol. The calcium chloride was used as the crosslinking agent. Fourier transform infrared spectroscopy (FTIR) was used to evaluate the drug-polymer interaction. The alginate spheres showed good rheological properties, drug content uniformity and high entrapment efficiency. The aceclofenac release from the spheres was slow and extended up to 10 hours. The drug loaded spheres exhibited good mucoadhesive property in the in vitro wash off test. The drug release from the optimized formulation (drug-sodium alginate-HPMC K15M; 1:0.9: 0.1 ratio) followed zero order kinetics and exhibited non-Fickian diffusion. The rate of release of aceclofenac decreased with increasing concentration of sodium alginate due to slow penetration of dissolution fluid in the spheres. The results suggest that alginate spheres can potentially deliver aceclofenac at zero-order controlled release following oral administration. The FTIR studies indicated the absence of the drug-polymer interaction in the solid state.

scholarly journals Adsorption of tetracycline antibiotics from an aqueous solution onto graphene oxide/calcium alginate composite fibers

RSC Advances ◽  
2018 ◽  
Vol 8 (5) ◽  
pp. 2616-2621 ◽  
Author(s):  
Haotian Zhu ◽  
Tao Chen ◽  
Jingquan Liu ◽  
Da Li
Keyword(s):  
Aqueous Solution ◽  
Graphene Oxide ◽  
Sodium Alginate ◽  
Calcium Alginate ◽  
Freeze Drying ◽  
Cross Linking ◽  
Composite Fibers ◽  
Drying Method ◽  
Tetracycline Antibiotics ◽  
Efficient Adsorbent

In this study, we report the preparation of a novel environmentally friendly and highly efficient adsorbent, graphene oxide/calcium alginate (GO/CA) composite fibers, via a freeze-drying method using calcium chloride as a cross-linking reagent between graphene oxide and sodium alginate.

scholarly journals Optimasi Pembuatan Mikrokapsul Kalsium-Alginat-EDTA Sebagai Adsorben Untuk Logam Kadmium

2020 ◽  
Vol 15 (4) ◽  
pp. 384
Author(s):  
Sani Widyastuti Pratiwi ◽  
Ayu Triastuti ◽  
Ratna Nurmalasari ◽  
Inggis Pinarti
Keyword(s):  
Sodium Alginate ◽  
Calcium Chloride ◽  
Functional Groups ◽  
Calcium Alginate ◽  
Chloride Concentration ◽  
Wave Number ◽  
Optimum Conditions ◽  
Retention Capacity ◽  
Alginate Concentration ◽  
Cadmium Metal

Cadmium was one of the metals classified in the type of nonessential heavy metal that classified as carcinogenic and is one of the pollutants in the environment, especially water. The content of cadmium in water tends to have very low levels, so certain techniques are needed to determine the level of pre concentration. In the pre concentration technique adsorbents were needed which could absorb cadmium, one of which is calcium-alginate microcapsule modified with EDTA. Calcium-alginate was  modified with EDTA to increase the ability of the microcapsule to absorb cadmium metal. The purpose of this study was to determine the optimum conditions for making Calcium-alginate-EDTA microcapsule in adsorbing cadmium. The stages of this research were optimization of Calcium-alginate-EDTA resin with variable in the form of Calcium chloride concentration (0.05 M; 0.1 M; 0.5 M; 1 M; and 2 M), EDTA mass (0.50 g ; 0.75 g; 1 g; 2 g and 2.5 g) and the concentration of sodium-alginate (0.5%; 1%, 1.5%; 2%, and 3%); Characterization of microcapsule functional groups by infrared spectrophotometry and determination of the retention capacity of Calcium-Alginate-EDTA microcapsule for cadmium absorption by atomic absorption spectrophotometry. The results of infrared characterization showed a change in transmittance in the functional groups C-O dan C-N that occurred in the microcapsule after binding to cadmium metal at wave number 1436.97 cm-1. The optimum conditions for making Calcium-alginate-EDTA resins were in conditions of 0.1 M Calcium chloride concentration, 1% sodium-alginate concentration and EDTA mass 0.75 g EDTA with retention capacity of  Cd was 0.0301 mg/g.

Investigation on Temperature-Sensitive Poly (N-Vinylcaprolactam) Modified Calcium Alginate Microspheres

2013 ◽  
Vol 631-632 ◽  
pp. 145-149
Author(s):  
Wen Chao Wang ◽  
Xiao Mei Ma ◽  
Wei Huan Xu ◽  
Yin Yin Li ◽  
Quan Ji ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Sodium Alginate ◽  
Temperature Sensitivity ◽  
Calcium Alginate ◽  
Temperature Sensitive ◽  
Release Behavior ◽  
Composite Microspheres ◽  
Mixed Aqueous Solution ◽  
Model Drug ◽  
Turbidity Method

Temperature-sensitive calcium alginate-based microspheres were prepared in two steps. Firstly, free-radical polymerization of temperature-sensitive N-vinylcaprolactam monomer was performed in aqueous solution of sodium alginate, yielding a mixed aqueous solution bearing temperature-sensitivity composed of poly(N-vinylcaprolactam), sodium alginate-graft- poly(N-vinylcaprolactam) and sodium alginate. Then temperature-sensitive composite microspheres were prepared by inverse emulsification-crosslinking using the as-prepared solution as water phase, n-hexane as oil phase, Span-85 and Tween-85 as emulsifiers and calcium chloride as crosslinker respectively. The morphology and temperature-sensitivity of the composite microspheres were investigated by scanning electron microscope and turbidity method respectively. The controlled release behavior of the microspheres towards temperature was investigated preliminarily using berberine as a model drug.

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