CONTROLLED RELEASE OF IMIDACLOPRID FROM POLY (STYRENE–DIACETONE CRYLAMIDE)-BASED NANOFORMULATION

Imidacloprid is a neonicotinoids insecticide, which is important for the cash crops such as tomato, rape and so on. The conventional formulation does not only increase the loss of pesticide but also leads to environmental pollution. Controlled-release formulations of pesticide are highly desirable not only for attaining the most effective utilization of the pesticide, but also for reducing environmental pollution. Pesticide imidacloprid was incorporated in poly (styrene–diacetone crylamide)-based formulation to obtain controlled release properties, and the imidacloprid nanocontrolled release formulation was characterized by infrared (IR) and field emission scanning electron microscope (FESEM). Factors related to loading efficiency, swelling and release behaviors of the formulation were investigated. It showed that the loading efficiency could reach about 40% (w/w). The values for the diffusion exponent "n" were in the range of 0.31–0.58, which indicated that the release of imidacloprid was diffusion-controlled. The time taken for 50% of the active ingredient to be released into water, T50, was also calculated for the comparison of formulations in different conditions. The results showed that the formulation with higher temperature and more diacetone crylamide had lower value of T50, which means a quicker release of the active ingredient. This study highlighted some pieces of evidence that improved pesticide incorporation and slower release were linked to potential interactions between the pesticide and the polymer.

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Controlled-release Formulations of Trifluralin Herbicide by Interfacial Polymerization as a Tool for Environmental Hazards

Biointerface Research in Applied Chemistry ◽

10.33263/briac116.1386613877 ◽

2021 ◽

Vol 11 (6) ◽

pp. 13866-13877

Keyword(s):

Controlled Release ◽

Active Ingredient ◽

Interfacial Polymerization ◽

Uv Light ◽

Environmental Hazards ◽

Environmental Hazard ◽

Uv Exposure ◽

Controlled Release Formulations ◽

1Hnmr Spectroscopy ◽

Herbicide Exposure

Trifluralin is a widely used herbicide that can be an environmental hazard due to its sensitivity to photodegradation and volatilization to the atmosphere. Using modern techniques, such as microencapsulation, may help maintain trifluralin activity for an appropriate period and reduce applications' quantity and frequency. This work aimed to develop controlled-release formulations of trifluralin by microencapsulation of the active ingredient using interfacial polymerization. The successful encapsulation of trifluralin in the polyurethane network was confirmed by IR and 1HNMR spectroscopy, showing the two compounds' corresponding signals. Dissipation of trifluralin in the microencapsulation and EC formulations were tested with the herbicide exposure to UV light in a reactor for 0, 2, 4, 6, and 8 h. The results showed that the formulation significantly affected herbicide dissipation (P≤0.01). With increasing UV exposure, the active ingredient in the EC formulation decreased linearly and reached 43% after 8 h. In comparison, only 0.9% of the initial herbicide level in the microencapsulation was lost during the same time. Our results indicated that an effective herbicide such as trifluralin can be protected from volatilization and photodegradation by developing a microencapsulation formulation.

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Atrazine persistence applied as commercial and xerogel formulations in oxisol

Planta Daninha ◽

10.1590/s0100-83582013000300018 ◽

2013 ◽

Vol 31 (3) ◽

pp. 667-675

Author(s):

M.M. Trezzi ◽

E.D. Marchesan ◽

R.A. Vidal ◽

E. Xavier ◽

D.P. Dick

Keyword(s):

Controlled Release ◽

Experimental Design ◽

Environmental Damage ◽

Herbicide Application ◽

Release Formulation ◽

Commercial Formulation ◽

Dissipation Kinetics ◽

Intensive Use ◽

Herbicide Atrazine ◽

Controlled Release Formulations

The intensive use of pesticides have contaminated the soil and groundwater. The application of herbicides as controlled release formulations may reduce the environmental damage related to their use because it may optimize the efficiency of the active ingredient and reducing thus the recommended dose. The objective of this study was to evaluate the persistence of the herbicide atrazine applied as commercial formulation (COM) and as controlled release formulation (xerogel - XER) in Oxisol. The experimental design used was split-plot randomized-blocks with four replications, in a (2 x 6) + 1 arrangement. The two formulations (COM and XER) were assigned to main plots and different atrazine concentrations (0, 3.200, 3.600, 4.200, 5.400 and 8.000 g atrazine ha-1) were assigned to sub-plots. Persistence was determined by means of dissipation kinetics and bioavailability tests. The methodology of bioassays to assess the atrazine availability is efficient and enables to distinguish the tested formulations. The availability of atrazine XER is higher than the commercial in two different periods: up to 5 days after herbicide application and at the 35th day after application. The XER formulation tends to be more persistent in relation to COM formulation.

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Simultaneous Intercalation of 1-Naphthylacetic Acid and Indole-3-butyric Acid into Layered Double Hydroxides and Controlled Release Properties

Journal of Nanomaterials ◽

10.1155/2014/862491 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Shifeng Li ◽

Yanming Shen ◽

Min Xiao ◽

Dongbin Liu ◽

Lihui Fan ◽

...

Keyword(s):

Controlled Release ◽

Butyric Acid ◽

Layered Double Hydroxides ◽

Ph Value ◽

Release Kinetics ◽

Release Formulation ◽

Pseudo Second Order ◽

Controlled Release Formulations ◽

Naphthylacetic Acid ◽

Double Hydroxides

Controlled release formulations have been shown to have potential in overcoming the drawbacks of conventional plant growth regulators formulations. A controlled-release formulation of 1-naphthylacetic acid (NAA) and indole-3-butyric acid (IBA) simultaneous intercalated MgAl-layered double hydroxides (LDHs) was prepared. The synthetic nanohybrid material was characterized by various techniques, and release kinetics was studied. NAA and IBA anions located in the gallery of MgAl-LDHs with bilayer arrangement, and the nanohybrids particles were of typical plate-like shape with the lateral size of 50–100 nm. The results revealed that NAA and IBA have been intercalated into the interlayer spaces of MgAl-LDHs. The release of NAA and IBA fits pseudo-second-order model and is dependent on temperature, pH value, and release medium. The nanohybrids of NAA and IBA simultaneously intercalated in LDHs possessed good controlled release properties.

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Oral Controlled-Release Formulation in Veterinary Medicine

Critical Reviews in Therapeutic Drug Carrier Systems ◽

10.1615/critrevtherdrugcarriersyst.v23.i3.10 ◽

2006 ◽

Vol 23 (3) ◽

pp. 167-204 ◽

Cited By ~ 4

Author(s):

Eran Lavy ◽

Amir Steinman ◽

Stefan Soback

Keyword(s):

Veterinary Medicine ◽

Controlled Release ◽

Release Formulation ◽

Controlled Release Formulation

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Formulation and Evaluation of Nelfinavir Extended Release Trilayer Matrix Tablets by Design of Experiment

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2018.11.5.6 ◽

2018 ◽

Vol 11 (5) ◽

pp. 4259-4268

Author(s):

Nirmala Rangu ◽

Gande Suresh

Keyword(s):

Controlled Release ◽

Drug Release ◽

Hydroxypropyl Methylcellulose ◽

Magnesium Stearate ◽

Zero Order ◽

Matrix Tablets ◽

Drug Dissolution ◽

Crystalline Cellulose ◽

Dissolution Profile ◽

Release Formulation

The present study was aimed to develop once-daily controlled release trilayer matrix tablets of nelfinavir to achieve zero-order drug release for sustained plasma concentration. Nelfinavir trilayer matrix tablets were prepared by direct compression method and consisted of middle active layer with different grades of hydroxypropyl methylcellulose (HPMC), PVP (Polyvinyl Pyrrolidine) K-30 and MCC (Micro Crystalline Cellulose). Barrier layers were prepared with Polyox WSR-303, Xanthan gum, microcrystalline cellulose and magnesium stearate. Based on the evaluation parameters, drug dissolution profile and release drug kinetics DF8 were found to be optimized formulation. The developed drug delivery system provided prolonged drug release rates over a period of 24 h. The release profile of the optimized formulation (DF8) was described by the zero-order and best fitted to Higuchi model. FT-IR studies confirmed that there were no chemical interactions between drug and excipients used in the formulation. These results indicate that the approach used could lead to a successful development of a controlled release formulation of nelfinavir in the management of AIDS.

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Optimization Study to Develop Once-a-day Controlled Release Formulation of Metoclopramide with Predictable Design Space

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/10.37285/ijpsn.2008.1.1.6 ◽

1970 ◽

Vol 1 (1) ◽

pp. 71-76

Author(s):

Rajesh Dubey ◽

Udaya K. Chowdary ◽

Venkateswarlu V.

Keyword(s):

Controlled Release ◽

Drug Release ◽

Design Space ◽

Release Kinetics ◽

Release Profile ◽

Release Formulation ◽

Linear Effect ◽

Controlled Release Formulation ◽

The Difference ◽

Face Centered

A controlled release formulation of metoclopramide was developed using a combination of hypromellose (HPMC) and hydrogenated castor oil (HCO). Developed formulations released the drug over 20 hr with release kinetics following Higuchi model. Compared to HCO, HPMC showed significantly higher influence in controlling the drug release at initial as well as later phase. The difference in the influence can be explained by the different swelling and erosion behaviour of the polymers. Effect of the polymers on release was optimized using a face-centered central composite design to generate a predictable design space. Statistical analysis of the drug release at various levels indicated a linear effect of the polymers’ levels on the drug release. The release profile of formulations containing the polymer levels at extremes of their ranges in design space was found to be similar to the predicted release profile

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High Loading Efficiency and Controlled Release of Bioactive Immunotherapeutic Proteins Using Vaterite Nanoparticles (Part. Part. Syst. Charact. 7/2021)

Particle & Particle Systems Characterization ◽

10.1002/ppsc.202170013 ◽

2021 ◽

Vol 38 (7) ◽

pp. 2170013

Author(s):

Ghizlane Choukrani ◽

Jimena Álvarez Freile ◽

Natasha Ustyanovska Avtenyuk ◽

Wei Wan ◽

Kerstin Zimmermann ◽

...

Keyword(s):

Controlled Release ◽

High Loading ◽

Loading Efficiency

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A New Approach to Developing Long-Acting Injectable Formulations of Anti-HIV Drugs: Poly(Ethylene Phosphoric Acid) Block Copolymers Increase the Efficiency of Tenofovir against HIV-1 in MT-4 Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22010340 ◽

2020 ◽

Vol 22 (1) ◽

pp. 340

Author(s):

Ilya Nifant’ev ◽

Andrei Siniavin ◽

Eduard Karamov ◽

Maxim Kosarev ◽

Sergey Kovalchuk ◽

...

Keyword(s):

Controlled Release ◽

Block Copolymers ◽

Phosphoric Acid ◽

Hiv Infection ◽

Targeted Delivery ◽

Release Formulation ◽

Poly Ethylene ◽

Long Acting ◽

Hiv Drugs ◽

Anti Hiv

Despite the world’s combined efforts, human immunodeficiency virus (HIV), the causative agent of AIDS, remains one of the world’s most serious public health challenges. High genetic variability of HIV complicates the development of anti-HIV vaccine, and there is an actual clinical need for increasing the efficiency of anti-HIV drugs in terms of targeted delivery and controlled release. Tenofovir (TFV), a nucleotide-analog reverse transcriptase inhibitor, has gained wide acceptance as a drug for pre-exposure prophylaxis or treatment of HIV infection. In our study, we explored the potential of tenofovir disoproxil (TFD) adducts with block copolymers of poly(ethylene glycol) monomethyl ether and poly(ethylene phosphoric acid) (mPEG-b-PEPA) as candidates for developing a long-acting/controlled-release formulation of TFV. Two types of mPEG-b-PEPA with numbers of ethylene phosphoric acid (EPA) fragments of 13 and 49 were synthesized by catalytic ring-opening polymerization, and used for preparing four types of adducts with TFD. Antiviral activity of [mPEG-b-PEPA]TFD or tenofovir disoproxil fumarate (TDF) was evaluated using the model of experimental HIV infection in vitro (MT-4/HIV-1IIIB). Judging by the values of the selectivity index (SI), TFD exhibited an up to 14-fold higher anti-HIV activity in the form of mPEG-b-PEPA adducts, thus demonstrating significant promise for further development of long-acting/controlled-release injectable TFV formulations.

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