Thermosensitive Interfacial Migration of 5-FU in the Microenvironment of Pluronic Block Copolymers

Chemotherapy is one of the most important ways to treat cancer. At present, chemotherapy medicines are mainly administered by intravenous injection or oral administration. However, systemic medical care requires the dosage of high concentrations of drugs to defeat the malignant tumor growth. In recent years, the use of polymer composites for local and sustained drug release has become an important field of research to minimize side effects due to high-concentration chemotherapy drugs. Here, 19F-{1H} heteronuclear Overhauser enhancement spectroscopy (HOESY) was used to study the micellular environment of the F-containing chemotherapeutic drug 5-FU in Pluronic F127, Pluronic L121, and F127/L121 binary blending composites. The distribution of 5-FU in micelles is related to the PEO and PPO segment length of Pluronic polymers and the environmental temperature. The drug release tests further confirm that if 5-FU medicines were loaded in the PPO segment inside the micelles, the purpose of the prolonged drug release carrier is achieved.

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Diffusion of lidocaine hydrochloride from lipid microparticles

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq0901033p ◽

2009 ◽

Vol 15 (1) ◽

pp. 33-35 ◽

Cited By ~ 4

Author(s):

Rada Pjanovic ◽

Radoslava Stojanovic ◽

Milana Sajber ◽

Jelena Veljkovic ◽

Nevenka Boskovic-Vragolovic ◽

...

Keyword(s):

Drug Release ◽

Diffusion Rate ◽

Drug Carriers ◽

Lidocaine Hydrochloride ◽

Diffusion Cell ◽

Sustained Drug Release ◽

Franz Diffusion Cell ◽

Diffusion Rates ◽

Hydrochloride Solution ◽

Prolonged Drug Release

Lipid particles, as drug carriers, are of increasing research interest, because a sustained drug release and avoidance of side effects could be achieved by using them. Lidocaine hydrochloride is a very efficient local anesthetic, but it has a short effect. The objective was to prolong the effect of the drug by encapsulating lidocaine hydrochloride in phospholipids microparticles. Two different procedures were used for the preparation of phospholipids microparticles. In both cases, phosphatidylcholine and lysophosphatidylcholine were used for the preparation of microparticles in which 5 % w/w lidocaine hydrochloride solution was encapsulated. The standard Franz diffusion cell was used for the experimental diffusion rate determination. The obtained results show that diffusion rate from microparticles is significantly lower than from the lidocaine hydrochloride solution, which means that this kind of microparticles could be used for the prolonged drug release. There was no much difference in diffusion rates from microparticles obtained by different procedures. That indicates that only the composition of the particles membrane has an influence on the lidocaine hydrochloride release rate.

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Formulation, Characterization and Release Behaviour of Metformin Hydrochloride Modified Release Tablet by Using Hydrophilic Polymers

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2021/v33i59b34395 ◽

2021 ◽

pp. 397-405

Author(s):

J. Thirumaran ◽

S. Tamilarasi ◽

S. Punitha ◽

T. Sivakumar ◽

C. N. Marimuthu ◽

...

Keyword(s):

Drug Release ◽

Sustained Release ◽

Methyl Cellulose ◽

High Viscosity ◽

Metformin Hydrochloride ◽

Modified Release ◽

High Concentration ◽

Release Property ◽

The Many ◽

Prolonged Drug Release

Amongst the many public health problems, the diabetes mellitus is considered as a chronic life-style related disease which is now growing as an epidemic in both developed as well as developing countries. The current study is about formulation of metformin hydrochloride tablet to confirm their sustained release property by using various polymers. The tablets are prepared by granulation techniques using binding solution containing polyvinyl pyrolline K30. The possible interaction between the pure metformin hydrochloride and polymers are identified by Fourier transform-infrared spectroscopy. Tablets were formulated with different polymers like Hydroxy propyl methyl cellulose K100 and sodium carboxymethyl cellulose. Matrix prepared with high concentration of HPMC K100 polymer retards the drug release up to 6 h at 59 %, but the formulation 2 (F2) showed 72.72% of drug release in 6 h. The release of drug from the F2 formulation was found to be prolonged drug release when compared to other formulations. Hence our study conclude that the HPMC K100 polymer containing formulation showed good sustained release property owing to the high gel strength and well high viscosity nature of the polymer.

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Synthesis, Characterization and in-vitro drug release studies of a macromolecular prodrug of Didanosine.

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v2i2.8845 ◽

2010 ◽

Vol 2 (2) ◽

Author(s):

Neeraj Agrawal ◽

M.J. Chandrasekar ◽

U.V. Sara ◽

Rohini A.

Keyword(s):

Drug Release ◽

Drug Level ◽

Drug Release Profile ◽

Sustained Drug Release ◽

In Vitro Drug Release ◽

Alkaline Environment ◽

Stomach Acid ◽

Release Studies ◽

Macromolecular Prodrug

A macromolecular prodrug of didanosine (ddI) for oral administration was synthesized and evaluated for in-vitro drug release profile. Didanosine was first coupled to 2-hydroxy ethyl methacrylate (HEMA) through a succinic spacer to form HEMA-Suc-ddI monomeric conjugate which was subsequently polymerized to yield Poly(HEMA-Suc-ddI) conjugate. The structures of the synthesized compounds were characterized by FT-IR, Mass and 1H-NMR spectroscopy. The prodrug was subjected for in-vitro drug release studies in buffers of pH 1.2 and 7.4 mimicking the upper and lower GIT. The results showed that the drug release from the polymeric backbone takes place in a sustained manner over a period of 24 h and the amount of drug released was comparatively higher at pH 7.4 indicating that the drug release takes place predominantly at the alkaline environment of the lower GIT rather than at the acidic environment of the upper GIT. This pH dependent sustained drug release behavior of the prodrug may be capable of reducing the dose limiting toxicities by maintaining the plasma drug level within the therapeutic range and increasing t1/2 of ddI. Moreover, the bioavailability of the drug should be improved as the prodrug releases ddI predominantly in the alkaline environment which will reduce the degradation of ddI in the stomach acid.

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The Toxicity of Castor Beans and its Treatment with Doxycycline in Local Rabbits

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.v9i2.13649 ◽

2018 ◽

Vol 9 (2) ◽

Cited By ~ 1

Author(s):

Nael Mohammed Sarheed ◽

Osamah Faisal Kokas ◽

Doaa Abd Alabas Muhammed Ridh

Keyword(s):

Castor Bean ◽

The Body ◽

Control Group ◽

High Concentration ◽

Biochemical Tests ◽

Doxycycline Treatment ◽

High Concentrations ◽

Physiological Tests ◽

Animal House ◽

Physiological And Biochemical

The plant of castor is widely spread in the Iraqi land, and characterized with containing ricin toxin, which has a very serious effects, and because the seeds of this plant scattered in the agricultural soil and rivers water, which increases the exposure of humans and animals to these beans. Objective: This experiment was designed to study the effect of high concentration of castor bean powder in some physiological and biochemical parameters and changes in some tissues of the body, as well as trying to use doxycycline to reduce the effects of ingestion of these seeds. Materials and Methods: In the experiment, 24 local rabbits were raised and fed in the Animal House of the Faculty of Medicine / Al-Muthanna University, then divided into four groups and treated for three weeks (21 days), Control group: treated with normal saline solution (0.9) orally throughout the experiment, G1: was treated orally with a concentration of 25 mg / kg of castor bean powder daily during the experiment, G2 : orally treated 25 mg / kg of castor bean and 25 mg / kg of doxycycline, G3: orally treated 25 mg / kg of castor powder with 50 mg / kg of doxycycline daily throughout the trial period. Results: The results of the experiment showed significant changes (P less than 0.05) in all physiological and biochemical blood tests when compared with control group. There was a significant decrease in PCV, Hb, RBC, T.protein and body weights, while demonstrated a significant increase in WBC, Urea, Creatinine, ALT, AST and ALP, with distortions in liver and kidney of animals that treated with Castor beans. In contrast, the treatment with doxycycline and caster beans showed significant improvement reflected by a normal proportion in physiological tests and biochemical tests with improvement in the tissues when compared to control group. Conclusions: It can be concluded from this study that castor bean has high toxic and pathogenic effects that may be dangerous to the life of the organism. Therefore, it is advisable to be cautious of these pills and avoid exposure to them, also recommended to take high concentrations of doxycycline treatment when infected with castor bean poisoning.

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Formulation and Evaluation of Chitosan-Polyaniline Nanocomposites for Controlled Release of Anticancer Drug Doxorubicin

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v8i2.13874 ◽

2018 ◽

Vol 8 (2) ◽

Author(s):

Dillip Kumar Behera ◽

Kampal Mishra ◽

Padmolochan Nayak

Keyword(s):

Tensile Strength ◽

Drug Release ◽

Nanocomposite Films ◽

Casting Method ◽

Sustained Drug Release ◽

In Vitro Drug Release ◽

Clay Particles ◽

Solution Casting Method ◽

Nanoclay Content

In this present work, chitosan (CS) crosslink with polyaniline (PANI) with montmorilonite (MMT) called as (CSPANI/MMT) and CS crosslink with PANI without MMT called as (CS-PANI) were prepared by employing the solution casting method. Further the formation of nanocomposites CS-PANI/MMT and CS-PANI were investigated using XRD, FTIR, SEM and tensile strength. Water uptake and swelling ratio of the CS-PANI and CS-PANI/MMT were found to decrease with increase in concentration of clay. Mechanical properties of the CS-PANI and CS-PANI/MMT were assessed in terms of tensile strength and extensibility using texture analyzer. Increase in tensile strength and reduction in extensibility was reported with increase in the nanoclay content. In vitro drug release study on CS-PANI and CS-PANI/MMT indicated pronounced sustained release of doxorubicin by the incorporation of clay particles in the CS polymer matrix. Overall CSPANI/MMT nanocomposite films exhibited improved mechanical and sustained drug release properties than CS-PANI.

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The Effects of Shock Vancomycin Concentrations on the Formation of Heteroresistance in Staphylococcus aureus

Antibiotics and Chemotherapy ◽

10.37489/0235-2990-2020-65-9-10-3-7 ◽

2020 ◽

Vol 65 (9-10) ◽

pp. 3-7

Author(s):

V. V. Gostev ◽

Yu. V. Sopova ◽

O. S. Kalinogorskaya ◽

M. E. Velizhanina ◽

I. V. Lazareva ◽

...

Keyword(s):

Staphylococcus Aureus ◽

In Vitro Selection ◽

Methicillin Resistant Staphylococcus Aureus ◽

High Concentration ◽

Short Term ◽

High Concentrations ◽

Selection Of ◽

Selection Of Resistance ◽

Test Cultures

Glycopeptides are the basis of the treatment of infections caused by MRSA (Methicillin-Resistant Staphylococcus aureus). Previously, it was demonstrated that antibiotic tolerant phenotypes are formed during selection of resistance under the influence of high concentrations of antibiotics. The present study uses a similar in vitro selection model with vancomycin. Clinical isolates of MRSA belonging to genetic lines ST8 and ST239, as well as the MSSA (ATCC29213) strain, were included in the experiment. Test isolates were incubated for five hours in a medium with a high concentration of vancomycin (50 μg/ml). Test cultures were grown on the medium without antibiotic for 18 hours after each exposure. A total of ten exposure cycles were performed. Vancomycin was characterized by bacteriostatic action; the proportion of surviving cells after exposure was 70–100%. After selection, there was a slight increase in the MIC to vancomycin (MIC 2 μg/ml), teicoplanin (MIC 1.5–3 μg/ml) and daptomycin (MIC 0.25–2 μg/ml). According to the results of PAP analysis, all strains showed an increase in the area under curve depending on the concentration of vancomycin after selection, while a heteroresistant phenotype (with PAP/AUC 0.9) was detected in three isolates. All isolates showed walK mutations (T188S, D235N, E261V, V380I, and G223D). Exposure to short-term shock concentrations of vancomycin promotes the formation of heteroresistance in both MRSA and MSSA. Formation of VISA phenotypes is possible during therapy with vancomycin.

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Growth responses of periphyton and chironomids exposed to biologically treated bleached kraft pulp mill effluent

Water Science & Technology ◽

10.2166/wst.1997.0553 ◽

1997 ◽

Vol 35 (2-3) ◽

pp. 339-345 ◽

Cited By ~ 1

Author(s):

M. G. Dubé ◽

J. M. Culp

Keyword(s):

Kraft Pulp ◽

Pulp Mill ◽

Pulp Mill Effluent ◽

Growth Responses ◽

High Concentration ◽

Wood Extractives ◽

Kraft Pulp Mill ◽

Bleached Kraft Pulp ◽

Low Levels ◽

High Concentrations

Experiments were conducted in artificial streams to determine the effects of increasing concentrations of biologically treated bleached kraft pulp mill effluent (BKPME) on periphyton and chironomid growth in the Thompson River, British Columbia. Periphyton growth, as determined by increases in chlorophyll a, was significantly stimulated at all effluent concentrations tested (0.25%, 0.5%, 1.0%, 5.0% and, 10.0%). Chironomid growth (individual weight) was also significantly stimulated at low effluent concentrations (≤1.0%). At higher concentrations (5.0% and 10.0%), chironomid growth was inhibited relative to the 1.0% treatment streams. Increases in growth were attributed to the effects of nutrient and organic enrichment from BKPME. The effluent contained high concentrations of phosphorus and appears to be an important source of carbon for benthic insects grazing on the biofilm. In high concentration effluent streams, chironomid growth decreased despite low levels of typical pulp mill contaminants. This suggests that other compounds in the effluent, such as wood extractives, may be inhibiting chironomid growth. These results support findings of field monitoring studies conducted in the Thompson River where changes in periphyton and chironomid abundance occurred downstream of the bleached kraft pulp mill.

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The Smart Dual-Stimuli Responsive Nanoparticles for Controlled AntiTumor Drug Release and Cancer Therapy

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200924110418 ◽

2020 ◽

Vol 20 ◽

Author(s):

Feng Wu ◽

Fei Qiu ◽

Siew Anthony Wai-Keong ◽

Yong Diao

Keyword(s):

Drug Delivery ◽

Cancer Therapy ◽

Drug Release ◽

Targeted Delivery ◽

Relevant Information ◽

Therapeutic Effects ◽

Stimuli Responsive ◽

Control Effect ◽

Chemotherapy Drugs ◽

Excellent Control

Background: In recent years, the emergence of stimuli-responsive nanoparticles makes drug delivery more efficient. As an intelligent and effective targeted delivery platform, it can reduce the side effects generated during drug transportation while enhancing the treatment efficacy. The stimuli-responsive nanoparticles can respond to different stimuli at corresponding times and locations to deliver and release their drugs and associated therapeutic effects. Objective: This review aims to inform researchers on the latest advances in the application of dual-stimuli responsive nanoparticles in precise drug delivery, with special attention to their design, drug release properties, and therapeutic effects. Syntheses of nanoparticles with simultaneous or sequential responses to two or more stimuli (pH-redox, pH-light, redoxlight, temperature-magnetic, pH-redox-temperature, redox-enzyme-light, etc.) and the applications of such responsivity properties for drugs control and release have become a hot topic of recent research. Methods: A database of relevant information for the production of this review was sourced, screened and analyzed from Pubmed, Web of Science, SciFinder by searching for the following keywords: “dual-stimuli responsive”, “controlled release”, “cancer therapy”, “synergistic treatment”. Results: Notably, the nanoparticles with dual-stimuli responsive function have an excellent control effect on drug delivery and release, playing a crucial part in the treatment of tumors. They can improve the encapsulation and delivery efficiency of hydrophobic chemotherapy drugs, combine chemo-photothermal therapies, apply imaging function in the diagnosis of tumors and even conduct multi-drugs delivery to overcome multi-drugs resistance (MDR). Conclusion: With the development of smart dual-stimuli responsive nanoparticles, cancer treatment methods will become more diverse and effective. All the stimuli-responsive nanoparticles functionalities exhibited their characteristics individually within the single nanosystem.

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Development and Optimization of Sustained Release Moxifloxacin Hydrochloride Loaded Nanoemulsion for Ophthalmic Drug Delivery: A 32 Factorial Design Approach

Micro and Nanosystems ◽

10.2174/1876402912999200826111031 ◽

2020 ◽

Vol 12 ◽

Author(s):

Sagar R. Pardeshi ◽

Harshal A. Mistari ◽

Rakhi S. Jain ◽

Pankaj R. Pardeshi ◽

Rahul L. Rajput ◽

...

Keyword(s):

Drug Release ◽

Sustained Release ◽

Factorial Design ◽

Water Solubility ◽

Tween 80 ◽

Drug Release Profile ◽

Sustained Drug Release ◽

Bacterial Conjunctivitis ◽

Promising Alternative

Background: Moxifloxacin is a BCS class I drug used in the treatment of bacterial conjunctivitis and keratitis. Despite its high water solubility, it possesses limited bioavailability due to anatomical and physiological constraints associated with the eyes which required multiple administrations to achieve a therapeutic effect. Objective: In order to prolong drug release and to improve antibacterial efficacy for the treatment of bacterial keratitis and conjunctivitis, moxifloxacin loaded nanoemulsion was developed. Methods: The concentration of oil (oleic acid), surfactant (tween 80), and cosurfactant (propylene glycol) were optimized by employing a 3-level 2-factorial design of experiment for the development of nanoemulsion. The developed nanoemulsion was characterized by particle size distribution, viscosity, refractive index, pH, drug content and release, transmission electron microscopy (TEM), and antibacterial study. The compatibility of the drug with the excipients was accessed by Fourier transform infrared spectroscopy (FTIR). Result: The average globule size was found to be 198.20 nm. The TEM study reveals the globules were nearly spherical and are well distributed. In vitro drug release profile for nanoemulsion shown sustained drug release (60.12% at the end of 6 h) compared to drug solution, where complete drug released within 2 h. The antibacterial effectiveness of the drug-loaded nanoemulsion was improved against S. aureus compared with the marketed formulation. Conclusion: The formulated sustained release nanoemulsion could be a promising alternative to eye drop with improved patient compliance by minimizing dosing frequency with improved antibacterial activity.

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