Preparation of Temozolomide Nano SustainedRelease Microsphere Material and Its Application in Treatment of Glioma

2020 ◽  
Vol 12 (10) ◽  
pp. 1476-1484
Author(s):  
Jun Zhao ◽  
Longbiao Xu ◽  
Ming Zhao ◽  
Chao Wei
Keyword(s):  
Sustained Release ◽  
Glycolic Acid ◽  
Drug Loading ◽  
Cell Activity ◽  
Morphological Characteristics ◽  
Release Curve ◽  
Emulsification Solvent Evaporation ◽  
The Right ◽  
The Brain ◽  
Sustained Release Microspheres

The polylactic acid/glycolic acid (PLGA) sustained-release microspheres are used as the main material for local sustained-release in the study. Ultrasonic emulsification-solvent evaporation method is applied to combine the sustained-release microspheres material with temozolomide to form a composite sustained-release microsphere (TMZ-PLGA-W). The ratio of lactic acid (LA) and glycolic acid (GA) was adjusted so as to test the morphological characteristics of TMZ-PLGA-W at different ratios. The amount of drug released and the encapsulation rate of the material at different time periods were calculated. The C6 glioma system was implanted into the right caudate nucleus of Wistar rats to obtain a rat intracranial glioma model. The models were divided into 5 groups according to different sustained-release materials, and each group had 10 rats. The brain tumor at different times were compared and the survival time of rats was statistically calculated. The TMZ-PLGA-W sustained-release microsphere material with LA/GA ratio of 25%/75% was selected and placed in C6 cells culturing incubator according to different drug loadings. The cell activity according to the culture time was observed. The results showed that the TMZ-PLGA-W sustained-release microspheres prepared in the study were stable in structure, uniform in size, and free of cracks. At the same time, the sustained-release curve showed that the microsphere material conformed to the biodynamic law, which could reduce the burst effect and prolong the sustained release of the drug. The application of TMZ-PLGA-W sustained-release microspheres can effectively inhibit the increase in the area of brain tumors in rats, and at the same time improve the survival rate of rats. The increase in the drug loading of the microspheres can further inhibit the growth of glioma cells.

scholarly journals Molecularly Imprinting Polymers (MIP) Based on Nitrogen Doped Carbon Dots and MIL-101(Fe) for Doxorubicin Hydrochloride Delivery

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1655
Author(s):  
Yuqiong Shi ◽  
Yuxuan Wang ◽  
Jinhua Zhu ◽  
Wei Liu ◽  
Md. Zaved H. Khan ◽  
...  
Keyword(s):  
Drug Loading ◽  
Cell Activity ◽  
Doxorubicin Hydrochloride ◽  
Optimal Drug ◽  
Specific Selectivity ◽  
Release Curve ◽  
Molecularly Imprinting Polymers ◽  
Doped Carbon Dots ◽  
Nitrogen Doped Carbon

MIL-based molecularly imprinted polymer (MIP) nanocomposites were successfully synthesized through a simple and versatile stirring auxiliary encapsulation method. MIP as a carrier has been applied to the highly efficient selective recognition and sustained release of doxorubicin hydrochloride (DOX). The adsorption mechanism and release behavior of MIP@DOX in vitro were also discussed. Adsorption studies showed that MIP using DOX as template had specific selectivity to DOX, and its optimal drug loading efficiency reached 97.99%. The adsorption isotherm accorded with Freundlich models. The cumulative release curve showed that at the conditions of pH 5.5 and 7.4, the nanomaterials have a slow-release effect on the release of DOX. In addition, the cytotoxicity and bioactivity of MIP nanoparticles on HepG2 and HL-7702 cell lines measured by MTT assay also proved their low toxicity and biological activity. The cell activity of HepG2 and HL-7702 incubated with MIP for 24 h was 69.9% and 76.07%, respectively. These results collectively illustrated that the MIP nano-materials synthesized in this study can be efficiently employed to the drug delivery systems.

Formulation optimization and in vitro characterization of granisetron-loaded polylactic-co-glycolic acid microspheres prepared by a dropping-in-liquid emulsification technique

2021 ◽  
Vol 18 ◽  
Author(s):  
Atef Mohammed Qasem Ahmed ◽  
Li-Qing Chen ◽  
Huan-Huan Du ◽  
Wei Sun ◽  
Qing-Ri Cao
Keyword(s):  
Particle Size ◽  
Sustained Release ◽  
Molecular Interactions ◽  
Glycolic Acid ◽  
Drug Loading ◽  
Plga Microspheres ◽  
Scanning Calorimetry ◽  
Medium Ph ◽  
Hardening Process

Purpose: Traditional dosage forms of granisetron (GRN) decrease patient compliance associated with repeated drug administration because of the short half-life of the drug. Methods: In this study, novel GRN-loaded polylactic-co-glycolic acid (PLGA) sustained release microspheres were prepared for the first time via a dropping-in-liquid emulsification technique. The effect of various factors, such as pH of the outer phase, Tween80, polyvinyl alcohol (PVA) concentrations, and hardening process, on the encapsulation efficiency (EE), drug loading (DL), and particle size of microspheres were extensively studied. The physicochemical properties, including drug release, surface morphology, crystallinity, thermal changes, and molecular interactions, were also studied. Results: GRN has a pH-dependent solubility and showed a remarkably high solubility under an acidic condition. The EE of the alkaline medium (pH 8) was higher than that of the acidic medium (pH 4.0). EE and DL decreased in the presence of Tween80 in the outer phase, whereas EE significantly increased during hardening. The particle size of microspheres was not affected by PVA and Tween80 concentrations, but it was influenced by PVA volume and hardening. X-ray diffraction and differential scanning calorimetry results showed that the physical state of the drug changed from a crystalline form to an amorphous form, thereby confirming that the drug was encapsulated into the PLGA matrix. Fourier transform-infrared spectroscopy confirmed that some molecular interactions occurred between the drug and the polymer. GRN-loaded PLGA microspheres showed sustained release profiles of over 90% on week 3. Conclusion: GRN-loaded PLGA microspheres with sustained release were successfully prepared, and they exhibited a relatively high EE without Tween 80 as an emulsifier and with hardening process.

A review on designing Poly (lactic-co-glycolic acid) nanoparticles as drug delivery systems

2020 ◽  
Vol 08 ◽  
Author(s):  
Sweet Naskar ◽  
Sanjoy Kumar Das ◽  
Suraj Sharma ◽  
Ketousetuo Kuotsu
Keyword(s):  
Drug Delivery ◽  
Glycolic Acid ◽  
Drug Loading ◽  
Surface Modifications ◽  
General Study ◽  
Salting Out ◽  
Preparation Methods ◽  
Supercritical Fluid Technology ◽  
Emulsification Solvent Evaporation ◽  
Diffusion Dialysis

: Poly (lactic-co-glycolic acid) (PLGA) is one of the versatile synthetic polymer comprehensively used in the pharmaceutical sectorbecause of its biocompatibility and biodegradability.These benefits lead to its application in the area of nanoparticles (NPs) for the drug delivery over the thirty years. This article offers to climb a general study of the different poly (lactic-co-glycolic acid) nanoparticles (PNPs) preparation methods such as emulsification-solvent evaporation, coacervation, emulsification solvent diffusion, dialysis, emulsification reverse salting out, spray drying nanoprecipitation, and supercritical fluid technology, from the methodological point of view.The physicochemical behavior of PNPs including morphology, drug loading, particle size and its distribution, surface charge, drug release, stability as well as cytotoxicity study and cellular uptake are briefly discussed. This survey additionally coordinates to bring a layout of the significant uses of PNPs in different drug delivery system over the three decades. At last, surface modifications of PNPs and PLGA nanocomplexes (NCs) are additionally examined.

Microspheres scar formation glaucoma filtration surgery area therapeutic effect—Based on rapamycin-chitosan-calcium alginate sustained-release

2020 ◽  
Vol 10 (6) ◽  
pp. 848-855
Author(s):  
Shasha Wang ◽  
Feiping Xu ◽  
Jie He ◽  
Tingyi Cao ◽  
Rui Liu ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Sustained Release ◽  
Release Rate ◽  
Calcium Alginate ◽  
Filtration Surgery ◽  
Glaucoma Filtration Surgery ◽  
Group A ◽  
Group B ◽  
The Right ◽  
Sustained Release Microspheres

To study the efficacy of rapamycin (RAPA)-chitosan (CS)-calcium alginate (CA) sustained-release microspheres on scar formation in a rabbit model of glaucoma filtration surgery. Eighty New Zealand white rabbits were randomly divided into four groups and a glaucoma filtration model was established by scleral bite through the eyes. RAPA-CS-CA sustained-release microspheres were implanted in the right eye of 40 rabbits (Group A) and CS blank sustained-release microspheres were implanted in the left eye (Group B). Another 40 rabbits were treated with a 0.2 g·L-1 RAPA cotton sheet in the right eye (Group C) and the left eye underwent a simple sclerotomy (Group D). The intraocular pressure, filter bleb, anterior chamber inflammation, complications, and corneal endothelial cell density were observed after the operation. Rabbits were euthanized for pathological examination 7 days, 14 days, and 21 days after the operation. The drug loading rate of RAPA-CS-CA sustainedrelease microspheres was (34.58±1.47)% and the encapsulation rate was (56.23±1.55)%. The microsphere release in vitro was relatively stable. The release rate of the microspheres during the burst was only 16.54%. After 49 days, the cumulative release rate of the microspheres reached 94.07% and the sustained release effect was significant within 45 days. Group A maintained low-level intraocular pressure for the longest period of time, followed by Group C, and then Group B and D. The survival time of filter vesicles in Group A was longer than that in other groups. There were no postoperative complications in each group. The conjunctival epithelium of Group A had better integrity and fewer subconjunctival fibroblasts than other groups. There was no obvious inflammation or infiltration around the filtering mouth and there were fewer new collagen fibers. RAPA-CS-CA slow-release microspheres safely and effectively inhibited the proliferation of fibroblasts and neonatal collagen fibers in rabbit glaucoma filtration surgery and significantly improved the success rate of glaucoma filtration surgery.

Different pH-Values of Release Medium Influence the Drug Release from PTX-PCL Microspheres

2012 ◽  
Vol 482-484 ◽  
pp. 2605-2608 ◽  
Author(s):  
Li Li Ruan ◽  
Da Xin Wang ◽  
You Wei Zhang ◽  
Jiong Xin Zhao ◽  
Xiu Fang Zhang ◽  
...  
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
High Performance ◽  
Drug Loading ◽  
In Vitro Release ◽  
Buffer Solution ◽  
Ph Values ◽  
Sustained Release Microspheres

In this paper we study in vitro release of paclitaxel-loade polycaprolactone sustained-release microspheres. Different pH values release medium is used to simulate pH conditions in different parts of body, and determination the paclitaxel in Microspheres by High Performance Liquid Chromatography according Chinese Pharmacopoeia 2010. The experimental results indicate that the microspheres release rates of same drug loading content in buffer solution of pH 7.35 is the fastest, and in the pH 1.2 is the slowest. The drug release behavior according to the first-order model and it is not affected by drug loading rate of microspheres. The prepared paclitaxel-loade polycaprolactone sustained-release microspheres has good sustained release effect in different release media, and the results can provide references for further study of in vivo release.

scholarly journals Study of Ethyl Cellulose Based Sustained Release Microspheres of Naproxen Sodium

2012 ◽  
Vol 10 (2) ◽  
pp. 123-129 ◽  
Author(s):  
Kowshik Sarkar ◽  
Sams Mohammad Anowar Sadat ◽  
Md Saiful Islam ◽  
Reza-ul Jalil
Keyword(s):  
Surface Morphology ◽  
Sustained Release ◽  
Ethyl Cellulose ◽  
Naproxen Sodium ◽  
Drug Loading ◽  
Phosphate Buffer Solution ◽  
Buffer Solution ◽  
Peg 6000 ◽  
Peg 600 ◽  
Sustained Release Microspheres

The present study was conducted to prepare sustained release microspheres of naproxen sodium using ethyl cellulose (Ethocel 20 cps) polymer. Three different plasticizers namely polyethyleneglycol 600   (PEG 600), polyethyleneglycol 6000 (PEG 6000) and triethyl citrate (TEC) were used at 10% (wt/wt) and 40% (wt/wt) level of the drug content. Prepared microspheres were characterized with respect to drug loading,   microsphere particle size, microsphere surface morphology and release behavior. Surface morphology of the microspheres was examined in a scanning electron microscope. Drug release was observed in phosphate buffer   solution of pH 6.8 for 8 hours. At 10% level of the plasticizers, percent release was 93.36%, 93.02% and   92.67% for PEG 600, PEG 6000 and TEC respectively after 8 hours. On the other hand, at 40% level, percent   release was 81.12%, 70.06% and 51.12% for PEG 600, PEG 6000 and TEC respectively after the same   duration. Release mechanisms followed case I or fickian model   DOI: http://dx.doi.org/10.3329/dujps.v10i2.11792   Dhaka Univ. J. Pharm. Sci. 10(2): 123-129, 2011 (December)  

The brain structure and neurosecretory cells of noctuid moth Anadevidia peponis: Noctuidae

1990 ◽  
Vol 48 (3) ◽  
pp. 436-437
Author(s):  
M. Sato ◽  
Y. Ogawa ◽  
M. Sasaki ◽  
T. Matsuo
Keyword(s):  
Biological Clock ◽  
Virgin Female ◽  
Basic Structure ◽  
Fixed Time ◽  
Neurosecretory Cells ◽  
Nerve Cells ◽  
Noctuid Moth ◽  
The Right ◽  
20 Nm ◽  
The Brain

A virgin female of the noctuid moth, a kind of noctuidae that eats cucumis, etc. performs calling at a fixed time of each day, depending on the length of a day. The photoreceptors that induce this calling are located around the neurosecretory cells (NSC) in the central portion of the protocerebrum. Besides, it is considered that the female’s biological clock is located also in the cerebral lobe. In order to elucidate the calling and the function of the biological clock, it is necessary to clarify the basic structure of the brain. The observation results of 12 or 30 day-old noctuid moths showed that their brains are basically composed of an outer and an inner portion-neural lamella (about 2.5 μm) of collagen fibril and perineurium cells. Furthermore, nerve cells surround the cerebral lobes, in which NSCs, mushroom bodies, and central nerve cells, etc. are observed. The NSCs are large-sized (20 to 30 μm dia.) cells, which are located in the pons intercerebralis of the head section and at the rear of the mushroom body (two each on the right and left). Furthermore, the cells were classified into two types: one having many free ribosoms 15 to 20 nm in dia. and the other having granules 150 to 350 nm in dia. (Fig. 1).

Polymeric Nanoparticles for Brain Drug Delivery - A Review

2020 ◽  
Vol 21 (9) ◽  
pp. 649-660
Author(s):  
Subashini Raman ◽  
Syed Mahmood ◽  
Ayah R. Hilles ◽  
Md Noushad Javed ◽  
Motia Azmana ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Surface Modification ◽  
Polymeric Nanoparticles ◽  
Drug Loading ◽  
Preparation Methods ◽  
Brain Drug Delivery ◽  
Polymeric Nanoparticle ◽  
Relationship Of ◽  
The Relationship ◽  
The Brain

Background: Blood-brain barrier (BBB) plays a most hindering role in drug delivery to the brain. Recent research comes out with the nanoparticles approach, is continuously working towards improving the delivery to the brain. Currently, polymeric nanoparticle is extensively involved in many therapies for spatial and temporal targeted areas delivery. Methods: We did a non-systematic review, and the literature was searched in Google, Science Direct and PubMed. An overview is provided for the formulation of polymeric nanoparticles using different methods, effect of surface modification on the nanoparticle properties with types of polymeric nanoparticles and preparation methods. An account of different nanomedicine employed with therapeutic agent to cross the BBB alone with biodistribution of the drugs. Results: We found that various types of polymeric nanoparticle systems are available and they prosper in delivering the therapeutic amount of the drug to the targeted area. The effect of physicochemical properties on nanoformulation includes change in their size, shape, elasticity, surface charge and hydrophobicity. Surface modification of polymers or nanocarriers is also vital in the formulation of nanoparticles to enhance targeting efficiency to the brain. Conclusion: More standardized methods for the preparation of nanoparticles and to assess the relationship of surface modification on drug delivery. While the preparation and its output like drug loading, particle size, and charge, permeation is always conflicted, so it requires more attention for the acceptance of nanoparticles for brain delivery.

ASSESSMENT OF PHYSIOLOGICAL PARAMETERS OF THE TRIGEMINAL AND COCHLEOVESTIBULAR SYSTEMS IN TEMPOROMANDIBULAR JOINT PAIN DYSFUNCTION

2020 ◽  
Vol 17 (2) ◽  
pp. 110-120
Author(s):  
N.D. Sorokina ◽  
◽  
L.R. Shahalieva ◽  
S.S. Pertsov ◽  
L.V. Polma ◽  
...  
Keyword(s):  
Nervous System ◽  
Evoked Potentials ◽  
Temporomandibular Joint ◽  
Differential Diagnostics ◽  
Autonomous Nervous System ◽  
Dental Diseases ◽  
Grade Ii ◽  
The Right ◽  
Distal Occlusion ◽  
The Brain

One of the most common causes of chronic pain in the facial region, including in the trigeminal nerve link, which is not associated with dental diseases, is pain dysfunction of the temporomandibular joint. At the same time, there is evidence in the literature that there are relationships between pain dysfunction of the temporomandibular joint, abnormal occlusion, cervical-muscular tonic phenomena, postural disorders, dysfunction of the Autonomous nervous system and cochleovestibular manifestations. At the same time, neurophysiological indicators of functional disorders in the maxillofacial region and intersystem interactions in pain dysfunction of the temporomandibular joint are insufficiently studied.Goal. The aim of the work is to evaluate the neurophysiological features of trigeminal afferentation in terms of trigeminal somatosensory evoked potentials (TSWP) and the auditory conducting system of the brain in terms of acoustic stem evoked potentials (ASVP) in distal occlusion of the dentition with pain dysfunction of the temporomandibular joint (TMJ) in comparison with physiological occlusion in students 18-21 years old. Material and methods. The main study included 41 students with distal occlusion (21 girls and 20 boys), (grade II Engl, symmetrically right and left in 14 people, and grade II Engl on the left and grade I on the right in 12 people, grade I on the left and grade II on the right in 15 people). All respondents with distal occlusion and who were practically healthy signed an informed consent to participate in the study. We used complex orthodontic methods of examination, subjective degree of severity and intensity of pain in the TMJ, assessment of the Autonomous nervous system (samples and tests), and neurophysiological methods for assessing TSVP and ASVP. Results. Significant differences in ASEP parameters were found in the group of respondents with distal occlusion in the form of a decrease in the latency period of peak I, III, and V compared to physiological occlusion, that correlated with the subjective assessment (in points) of cochleovestibular disorders. According to the TSVP study, a decrease in the duration of latent periods was found, which indicates an increased excitability of non-specific brain stem structures at the medullo-ponto-mesencephalic level compared to the control group. Conclusions. The results obtained are supposed to be used for differential diagnostics, including such dental diseases as TMJ pain dysfunction, occlusion abnormalities accompanied by pain syndrome. Additional functional diagnostics of multi-modal VP of the brain (acoustic evoked potentials, trigeminal evoked potentials) can be performed in conjunction with indicators of autonomic nervous system dysfunction, with parameters of severity of clinical symptoms of cochleovestibular disorders, musculoskeletal dysfunction the maxillofacial area, with indicators of pain, which will determine the tactics and effectiveness of subsequent treatment.

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