scholarly journals Controlled Release Fertilizer Encapsulated by Glutaraldehyde-Crosslinked Chitosan Using Freeze-Drying Method

2020 ◽  
Vol 20 (6) ◽  
pp. 1414
Author(s):  
Adhitasari Suratman ◽  
Dwi Ratih Purwaningsih ◽  
Eko Sri Kunarti ◽  
Agus Kuncaka
Keyword(s):  
Controlled Release ◽  
Environmental Pollution ◽  
Freeze Drying ◽  
Release Kinetics ◽  
Drying Method ◽  
Air Drying ◽  
Controlled Release Fertilizer ◽  
Npk Fertilizer ◽  
Crosslinked Chitosan ◽  
Kinetics Of

A new encapsulation of NPK fertilizer hydrogel granules made from glutaraldehyde crosslinked chitosan has been successfully fabricated. This designed fertilizer was aimed to maximize the fertilizing process in the soil, as the environmental pollution affected by the excess release of the nutrients can be prevented. The granule was prepared from biodegradable chitosan crosslinked with glutaraldehyde by applying a method of air and freeze-drying. The release test proved that this designed fertilizer showed a good performance as a Controlled Release Fertilizer (CRF) in which the hydrogel granules could absorb and deposit large amounts of NPK. Later on, they could also release large amounts of NPK as well, unlike several types of CRFs. The release percentage of NPK out of the granules tended to decrease with an increase of pH at a range close to the average pH of the soil, which is neutral to base. Comparing two methods, the freeze-drying technique, which yields a bigger pore size, showed a higher release percentage than air-drying. The release kinetics of the granules followed the Korsmeyer-Peppas model.

The effect of zeolite addition and freeze-drying method on alginat beads for controlled release fertilizer

2020 ◽  
Author(s):  
Adhitasari Suratman ◽  
Nurul Pramita ◽  
Pradiya Nadya Agasta ◽  
Dwi Ratih Purwaningsih ◽  
Agus Kuncaka ◽  
...  
Keyword(s):  
Controlled Release ◽  
Freeze Drying ◽  
Drying Method ◽  
Controlled Release Fertilizer

Mathematical Modeling of Controlled-Release Kinetics of Herbicides in a Dynamic-Water-Bath System

2001 ◽  
pp. 563-574
Author(s):  
Félix M. Pereira ◽  
Adilson R. Gonçalves ◽  
André Ferraz ◽  
Flávio T. Silva ◽  
Samuel C. Oliveira
Keyword(s):  
Mathematical Modeling ◽  
Controlled Release ◽  
Release Kinetics ◽  
Water Bath ◽  
Kinetics Of

scholarly journals Morphology and Release Kinetics of Protein-Loaded Porous Poly(L-Lactic Acid) Spheres Prepared by Freeze-Drying Technique

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Takashi Sasaki ◽  
Kazuki Tanaka ◽  
Daisuke Morino ◽  
Kensuke Sakurai
Keyword(s):  
Lactic Acid ◽  
Freeze Drying ◽  
Release Kinetics ◽  
Particle Surface ◽  
Spherical Particles ◽  
Freeze Dried ◽  
Model Drug ◽  
Drug Compound ◽  
Kinetics Of ◽  
Step Mechanism

Freeze-drying a biodegradable polymer, poly(L-lactic acid) (PLLA), from 1,4-dioxane solutions provided very porous spherical particles of ca. 3 mm in radius with specific surface area of 8–13 m2 g−1. The surface of the particle was found to be less porous compared with its interior. To apply the freeze-dried PLLA (FDPLLA) to drug delivery system, its morphology and drug releasing kinetics were investigated, bovine serum albumin (BSA) being used as a model drug compound. Immersion of FDPLLA into a BSA aqueous solution gave BSA-loaded FDPLLA, where mass fraction of the adsorbed BSA reached up to 79%. Time-dependent release profile of BSA in water suggested a two-step mechanism: (1) very rapid release of BSA deposited on and near the particle surface, which results in an initial burst, and (2) leaching of BSA from the interior of the particle by the diffusion process. It was suggested that the latter process is largely governed by the surface porosity. The porosity of both the interior and surface was found to decrease remarkably as the concentration of the original PLLA/1,4-dioxane solution increases, C0. Thus, C0 is a key parameter that controls the loading and releasing of BSA.

Compressed nanofibrous oral tablets: An ingenious way for controlled release kinetics of Amphotericin-B loaded gelatin nanofibers

2019 ◽  
Vol 19 ◽  
pp. 100367 ◽  
Author(s):  
Anindita Laha ◽  
Mrunalini K. Gaydhane ◽  
Chandra S. Sharma ◽  
Saptarshi Majumdar
Keyword(s):  
Controlled Release ◽  
Amphotericin B ◽  
Release Kinetics ◽  
Kinetics Of

Freeze-Drying Investigations of Antlers

2012 ◽  
Vol 195-196 ◽  
pp. 441-446
Author(s):  
Jun Liu ◽  
Shi Wei Zhang ◽  
Zhi Jun Zhang
Keyword(s):  
Freeze Drying ◽  
Eutectic Temperature ◽  
Tissue Structure ◽  
Chemical Compositions ◽  
Drying Method ◽  
Drying Process ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Freeze Dried

In this paper, the vacuum freeze-drying experiments of both antler slices and whole antlers are reported in details. The moisture content and the eutectic temperature of antler were measured. A 22 h process curve of antler slice freeze drying was obtained. The freeze drying process of whole antler was also investigated. The microscopic tissue structure was observed and chemical compositions were analyzed for those freeze-dried whole antlers in comparison with the traditional water boiling and hot air drying method. More nutrients were retained for freeze drying in addition to the better physical properties than traditional drying.

Ultrastructure of Epicuticular Wax in Canola

1989 ◽  
Vol 44 (7-8) ◽  
pp. 705-711 ◽  
Author(s):  
K. L. Conn ◽  
J. P. Tewari
Keyword(s):  
Freeze Drying ◽  
Brassica Campestris ◽  
Amorphous Layer ◽  
Epicuticular Wax ◽  
Drying Methods ◽  
Specimen Preparation ◽  
Drying Method ◽  
Air Drying ◽  
Species Specific ◽  
Wax Crystals

Ultrastructure of the epicuticular wax of four commercially grown Canadian cultivars of canola (Brassica campestris cvs. Tobin and Candle, B. napus cvs. Altex and Westar) was investigated. Freeze-drying and air-drying methods of specimen preparation for scanning electron microscopy were compared. The freeze-drying method resulted in disruption and possible washing away of wax crystals, whereas there was no visible damage with the air-drying method. The freeze-drying method provided evidence for an amorphous layer of wax beneath the wax crystals. Ultrastructure of wax in the four cultivars was generally similar. All cultivars had an evenly distributed layer of wax crystals superimposed on an amorphous layer of wax. Some trends such as density of wax on leaves and siliques appeared to be species-specific, whereas density of wax on stems did not. There appeared to be at least three types of wax crystals present. These included plate-like, filamentous, and rod-like crystals. The rods were present singly or in blocks.

Evaluation of Kollicoat SR 30D and Kollicoat EMM 30D as Matrix Former for Controlled Release Drug Delivery

1970 ◽  
Vol 4 (1) ◽  
Author(s):  
Mohammad Salim Hossain ◽  
Reza-ul Jalil ◽  
Selim Reza ◽  
Mohiuddin Abdul Quadir ◽  
CF Hossain
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Matrix Effects ◽  
Release Kinetics ◽  
Polymeric Systems ◽  
Release Drug ◽  
The Matrix ◽  
Kinetics Of ◽  
Order Pattern ◽  
Drug Liberation

Efficiency of kollicoat EMM 30 D and SR 30D as matrix forming material was investigated. It was found that, theophylline loaded granules prepared with these two polymers could not sustain drug release for a significant period of time. However, compression of these granules into tablets retarded drug release for up to 8 hours. Release was faster from EMM 30D polymeric system than that from SR 30D matrix. Effects of fillers and rate modifiers on drug liberation have been assessed. Incorporation of Avicel RC 591 and starch caused substantial release of theophylline from both the polymeric systems. Avicel PH 101 intensified the retardation effect of both EMM 30D and SR 30D on theophylline release. HPMC 50 cps, when added to the matrix, caused the release of theophylline to follow near zero order pattern. Increasing the content of HPMC in both EMM 30D and SR 30D compressed tablets decreased the rate and extent of theophylline release. In the presence of excipients, no significant differences between rate and extent of drug release from EMM 30D and SR 30D systems were found. Biexponential equation was applied to explore and explain drug release kinetics. It was found that drug release followed Fickian or case I kinetics from EMM 30D compressed tablet while anomalous or non-fickian kinetics of drug release was observed for SR 30D system. Key words: Kolliocoat SR 30D, Kollicoat EMM 30D, Theophylline, Matrix system, Controlled release Dhaka Univ. J. Pharm. Sci. Vol.4(1) 2005 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

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