Crosslinking-Dependent Drug Kinetics in Hydrogels for Ophthalmic Delivery

Drug-diffusion kinetics in 2-hydroxyethyl methacrylate hydrogels were studied as a function of the crosslinking density and porosity. By varying the concentration of the crosslinker, tetraethylene glycol dimethacrylate, we demonstrated how the release of Timolol maleate could be optimized to allow for efficient drug delivery. FTIR and spectrophotometry supplied optical inferences into the functional groups present. By studying the swelling and degradation of hydrogels, supplemented with drug-release kinetics studies, the relationship between these two tenets could be formulated.

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Controlled release and release kinetics studies of boron through the functional formulation of carboxymethyl tamarind kernel gum-based superabsorbent hydrogel

Polymer Bulletin ◽

10.1007/s00289-021-03634-9 ◽

2021 ◽

Author(s):

Khushbu ◽

Sudhir G. Warkar ◽

Nandkishore Thombare

Keyword(s):

Controlled Release ◽

Release Kinetics ◽

Superabsorbent Hydrogel ◽

Kinetics Studies ◽

Functional Formulation ◽

Tamarind Kernel

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FORMULATION AND CHARACTERIZATION OF TIMOLOL MALEATE-LOADED NANOPARTICLES GEL BY IONIC GELATION METHOD USING CHITOSAN AND SODIUM ALGINATE

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2019v11i6.34983 ◽

2019 ◽

pp. 48-54 ◽

Cited By ~ 1

Author(s):

RISA AHDYANI ◽

LARAS NOVITASARI ◽

RONNY MARTIEN

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Sodium Alginate ◽

Release Kinetics ◽

In Vitro Release ◽

Entrapment Efficiency ◽

Polydispersity Index ◽

Ionic Gelation ◽

Timolol Maleate ◽

Optimum Formula

Objective: The objectives of this study were to formulate and characterize nanoparticles gel of timolol maleate (TM) by ionic gelation method using chitosan (CS) and sodium alginate (SA). Methods: Optimization was carried out by factorial design using Design Expert®10.0.1 software to obtain the concentration of CS, SA, and calcium chloride (CaCl2) to produce the optimum formula of TM nanoparticles. The optimum formula was characterized for particle size, polydispersity index, entrapment efficiency, Zeta potential, and molecular structure. Hydroxy Propyl Methyl Cellulose (HPMC) K15 was incorporated into optimum formula to form nanoparticles gel of TM and carried out in vivo release study using the Franz Diffusion Cell. Results: TM nanoparticles was successfully prepared with concentration of CS, SA, and CaCl2 of 0.01 % (w/v), 0.1 % (w/v), and 0.25 % (w/v), respectively. The particle size, polydispersity index, entrapment efficiency, and Zeta potential were found to be 200.47±4.20 nm, 0.27±0.0154, 35.23±4.55 %, and-5.68±1.80 mV, respectively. The result of FTIR spectra indicated TM-loaded in the nanoparticles system. In vitro release profile of TM-loaded nanoparticles gel showed controlled release and the Korsmeyer-Peppas model was found to be the best fit for drug release kinetics. Conclusion: TM-loaded CS/SA nanoparticles gel was successfully prepared and could be considered as a promising candidate for controlled TM delivery of infantile hemangioma treatment.

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

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i1.15199 ◽

2016 ◽

Vol 9 (1) ◽

pp. 79 ◽

Cited By ~ 2

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

Objective: 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.Methods: 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 in vitro release profile of the ocuserts. Finally, accelerated stability studies and the release kinetics were performed on the optimised formulation.Results: 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. Conclusion: 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, in vitro drug release and stability.

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In vitro bioactivity and drug release kinetics studies of mesoporous silica-biopolymer composites

Journal of Porous Materials ◽

10.1007/s10934-015-0027-5 ◽

2015 ◽

Vol 22 (6) ◽

pp. 1465-1472 ◽

Cited By ~ 5

Author(s):

M. Narasimha Reddy ◽

K. K. Cheralathan ◽

S. Sasikumar

Keyword(s):

Drug Release ◽

Mesoporous Silica ◽

Release Kinetics ◽

In Vitro Bioactivity ◽

Drug Release Kinetics ◽

Kinetics Studies ◽

Biopolymer Composites

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Synthesis of poly(2-hydroxyethyl methacrylate)-based molecularly imprinted polymer nanoparticles containing timolol maleate: morphological, thermal, and drug release along with cell biocompatibility studies

Polymers for Advanced Technologies ◽

10.1002/pat.3986 ◽

2016 ◽

Vol 28 (7) ◽

pp. 828-841 ◽

Cited By ~ 9

Author(s):

Robabeh Aeinehvand ◽

Payam Zahedi ◽

Shahab Kashani-Rahimi ◽

Mahshid Fallah-Darrehchi ◽

Mohammad Shamsi

Keyword(s):

Drug Release ◽

Molecularly Imprinted Polymer ◽

Polymer Nanoparticles ◽

Hydroxyethyl Methacrylate ◽

Timolol Maleate ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Cell Biocompatibility

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Temperature-responsive hydrogels containing new LCST methacrylate macromonomers

e-Polymers ◽

10.1515/epoly.2007.7.1.998 ◽

2007 ◽

Vol 7 (1) ◽

Author(s):

Anna Korytkowska-Wałach ◽

Anna Porwoł ◽

Mirosław Gibas

Keyword(s):

Phase Transition ◽

Biomedical Applications ◽

Tetraethylene Glycol ◽

Temperature Sensitive ◽

Hydroxyethyl Methacrylate ◽

Temperature Responsive ◽

Michael Type Addition ◽

Responsive Hydrogels ◽

Ether Ester ◽

Gel Transition

AbstractA series of hydrogels were synthesized: homopolymers of new temperature-sensitive methacrylate macromonomers of ether-ester structure, derived from monomethacrylate of tetraethylene glycol via Michael-type addition - oligo(TTEGMMA), and copolymers of oligo(TTEGMMA) with N-isopropylacrylamide (NIPAAm) or 2-hydroxyethyl methacrylate (HEMA). Hydrogels based on oligo(TTEGMMA) demonstrate broad volume phase transition. Combination of oligo(TTEGMMA) with NIPAAm or HEMA yielded hydrogels having narrower phase transition and lower gel transition temperature (LGTT) up to 43 °C at the most, which is in the range of interest for most biomedical applications.

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Bio-Based Hydrogels Composed of Humic Matter and Pectins of Different Degree of Methyl-Esterification

Molecules ◽

10.3390/molecules25122936 ◽

2020 ◽

Vol 25 (12) ◽

pp. 2936

Author(s):

Assunta Nuzzo ◽

Pierluigi Mazzei ◽

Davide Savy ◽

Vincenzo Di Meo ◽

Alessandro Piccolo

Keyword(s):

Release Kinetics ◽

Morphological Structure ◽

13C Nmr Spectroscopy ◽

Crosslinking Density ◽

Resonance Imaging ◽

Ability To Work ◽

Methyl Esterification ◽

Manure Compost ◽

Kinetics Of ◽

Solid State 13C Nmr

We prepared humo-pectic hydrogels through ionotropic gelation by crosslinking natural pectins of different degree of methyl-esterification with either humic substances (HS) extracted from cow manure compost or humic-like substances (HULIS) from depolymerized lignocellulose biorefinery waste. The hydrogels were characterized by solid-state 13C-NMR spectroscopy, scanning electron microscopy, spectroscopic magnetic resonance imaging and rheological analyses. Their ability to work as controlled release systems was tested by following the release kinetics of a previously incorporated model phenolic compound, like phloroglucinol. Our results indicated that the release properties of hydrogels were influenced by the molecular composition of HS and HULIS and by the different degrees of methyl-esterification of pectins. The hydrogel made by the high methoxyl pectin and HS showed the fastest rate of phloroglucinol release, and this was attributed not only to its morphological structure and crosslinking density but also to the least formation of ionic interactions between phloroglucinol and the polysaccharidic chains. Our study suggests that the efficiency of novel humo-pectic hydrogels as sustainable carriers of agroproducts to crops is related to a careful choice of the characteristics of their components.

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Release Kinetics of Phosphorus in Sediments from Baihua Lake

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.599.91 ◽

2012 ◽

Vol 599 ◽

pp. 91-95 ◽

Cited By ~ 1

Author(s):

Jin Mei ◽

Ji Wei Hu ◽

Xian Fei Huang ◽

Li Ya Fu ◽

Jin Luo ◽

...

Keyword(s):

Organic Phosphorus ◽

Release Kinetics ◽

Phosphorus Release ◽

Release Kinetic ◽

Iron Aluminum ◽

P Content ◽

Elovich Equation ◽

Release Data ◽

The Relationship ◽

Kinetics Of

Release kinetics of phosphorus in 17 sediments samples collected from Baihua Lake were determined, and the relationship between the phosphorus release kinetic parameters and the sediment composition was also investigated. The results showed that both the Elovich equation and power function equation were valid models for describing the phosphorus release data in the 17 sediments. Within the beginning 12 h, the rate of phosphorus release was high, and then decreased. Our correlation analysis demonstrates that there were no significant correlations between the maximum capacity of phosphorus release (Qmax) and the content of total nitrogen (TN), organic matter (OM), calcium-bound phosphorus (Ca-P), and organic phosphorus (OP). But the correlation between Qmax and iron/aluminum-bound phosphorus (Fe/Al-P) content was positive (R2 = 0.6064, P < 0.01), suggesting that Fe/Al-P might be the main contributor to the released phosphorus in the sediments.

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