Ocular pharmacoscintigraphic and aqueous humoral drug availability of ganciclovir-loaded mucoadhesive nanoparticles in rabbits

AbstractThe present report describes the improved ocular retention and aqueous humoral drug availability of ganciclovir (GCV) when administered via topical instillation of different kind of nanoparticles onto the rabbit eye. GCV was loaded into PLGA nanoparticles, chitosan-coated nanoparticles and chitosan-coated niosomal nanoparticles. All three formulations contained nanoparticles equally round in shape with a mean particle size in the range of 180–200 nm. The ocular corneal retention property was evaluated by gamma scintigraphy, revealing that the clearance was slowest in the case of the chitosan-containing formulations. GCV in chitosan-coated PLGA nanoparticles and chitosan-coated niosomal nanoparticles showed approx. 6-fold higher aqueous humor drug availability as compared to a GCV solution and nearly 2.5-fold higher as compared to the chitosan-lacking GCV-PLGA nanoparticles. The results indicate that the use of a mucoadhesive chitosan coating can improve the ocular residence time and aqueous humoral availability of GCV when administered topically in nanoparticles.

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Continuous citrate‐capped gold nanoparticle synthesis in a two‐phase flow reactor

Journal of Flow Chemistry ◽

10.1007/s41981-021-00172-3 ◽

2021 ◽

Author(s):

Spyridon Damilos ◽

Ioannis Alissandratos ◽

Luca Panariello ◽

Anand N. P. Radhakrishnan ◽

Enhong Cao ◽

...

Keyword(s):

Particle Size ◽

Gold Nanoparticles ◽

Residence Time ◽

Flow Reactor ◽

Phase Flow ◽

Continuous Manufacturing ◽

Two Phase ◽

Process Yield ◽

Au Nps ◽

Manufacturing Platform

AbstractA continuous manufacturing platform was developed for the synthesis of aqueous colloidal 10–20 nm gold nanoparticles (Au NPs) in a flow reactor using chloroauric acid, sodium citrate and citric acid at 95 oC and 2.3 bar(a) pressure. The use of a two-phase flow system – using heptane as the continuous phase – prevented fouling on the reactor walls, while improving the residence time distribution. Continuous syntheses for up to 2 h demonstrated its potential application for continuous manufacturing, while live quality control was established using online UV-Vis photospectrometry that monitored the particle size and process yield. The synthesis was stable and reproducible over time for gold precursor concentration above 0.23 mM (after mixing), resulting in average particle size between 12 and 15 nm. A hydrophobic membrane separator provided successful separation of the aqueous and organic phases and collection of colloidal Au NPs in flow. Process yield increased at higher inlet flow rates (from 70 % to almost 100 %), due to lower residence time of the colloidal solution in the separator resulting in less fouling in the PTFE membrane. This study addresses the challenges for the translation of the synthesis from batch to flow and provides tools for the development of a continuous manufacturing platform for gold nanoparticles.Graphical abstract

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Effect of Chitosan Coating on PLGA Nanoparticles for Oral Delivery of Thymoquinone: In Vitro, Ex Vivo, and Cancer Cell Line Assessments

Coatings ◽

10.3390/coatings11010006 ◽

2020 ◽

Vol 11 (1) ◽

pp. 6

Author(s):

Sultan Alshehri ◽

Syed Sarim Imam ◽

Md Rizwanullah ◽

Khalid Umar Fakhri ◽

Mohd Moshahid Alam Rizvi ◽

...

Keyword(s):

Breast Cancer ◽

Particle Size ◽

Oral Delivery ◽

Ex Vivo ◽

Cancer Cell Line ◽

Entrapment Efficiency ◽

Plga Nanoparticles ◽

Cancer Management ◽

Mcf 7

In the present study, thymoquinone (TQ)-encapsulated chitosan- (CS)-coated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles (NPs) were formulated using the emulsion evaporation method. NPs were optimized by using 33-QbD approach for improved efficacy against breast cancer. The optimized thymoquinone loaded chitosan coated Poly (d,l-lactide-co-glycolide) nanoparticles (TQ-CS-PLGA-NPs) were successfully characterized by different in vitro and ex vivo experiments as well as evaluated for cytotoxicity in MDA-MB-231 and MCF-7 cell lines. The surface coating of PLGA-NPs was completed by CS coating and there were no significant changes in particle size and entrapment efficiency (EE) observed. The developed TQ-CS-PLGA-NPs showed particle size, polydispersibility index (PDI), and %EE in the range between 126.03–196.71 nm, 0.118–0.205, and 62.75%–92.17%. The high and prolonged TQ release rate was achieved from TQ-PLGA-NPs and TQ-CS-PLGA-NPs. The optimized TQ-CS-PLGA-NPs showed significantly higher mucoadhesion and intestinal permeation compared to uncoated TQ-PLGA-NPs and TQ suspension. Furthermore, TQ-CS-PLGA-NPs showed statistically enhanced antioxidant potential and cytotoxicity against MDA-MB-231 and MCF-7 cells compared to uncoated TQ-PLGA-NPs and pure TQ. On the basis of the above findings, it may be stated that chitosan-coated TQ-PLGA-NPs represent a great potential for breast cancer management.

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The Arterially Perfused Enucleated Rabbit Eye as a Model for Studying Aqueous Humor Formation

Ophthalmic Research ◽

10.1159/000265264 ◽

1983 ◽

Vol 15 (5) ◽

pp. 225-233 ◽

Cited By ~ 5

Author(s):

T. Kodama ◽

V.N. Reddy ◽

F.J. Macri

Keyword(s):

Aqueous Humor ◽

Rabbit Eye

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Remote-Controllable Bone-Targeted Delivery of Estradiol For the Treatment of Ovariectomy-Induced Osteoporosis in Rats

10.21203/rs.3.rs-628262/v1 ◽

2021 ◽

Author(s):

Dehao Fu ◽

Yuanyuan Guo ◽

Yongwei Liu ◽

Chen Shi ◽

Tingting Wu ◽

...

Keyword(s):

Particle Size ◽

Bone Tissue ◽

Targeted Delivery ◽

Hormone Replacement ◽

Plga Nanoparticles ◽

Raw 264.7 Cells ◽

Diffusion Method ◽

Tissue Destruction ◽

Trap 5B ◽

Post Menopausal

Abstract BackgroundOsteoporosis (OP) is a systemic skeletal disease marked by bone mass reduction and bone tissue destruction. Hormone replacement therapy is an effective treatment for post-menopausal OP, but estrogen has poor tissue selectivity and severe side effects.ResultsIn this study, we constructed a poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs)-based drug delivery system to co-load 17β estradiol (E2) and iron oxide (Fe3O4) together, modified with alendronate (AL) to achieve bone targeting and realize a magnetically remote-controllable drug release. The NPs were fabricated through the emulsion solvent diffusion method. The particle size was approximately 200 nm while the encapsulation efficiency of E2 was 58.34 ± 9.21%. The NPs were found to be spherical with a homogenous distribution of particle size. The NPs showed good stability, good biocompatibility, high encapsulation ability of E2 and excellent magnetic properties. The NPs could be effectively taken up by Raw 264.7 cells and were effective in enriching drugs in bone tissue. The co-loaded NPs exposed to an external magnetic field ameliorated OVX-induced bone loss through increased BV/TV, decreased Tb.N and Tb.Sp, improved bone strength, increased PINP and OC, and downregulated CTX and TRAP-5b. The haematological index and histopathological analyses displayed the NPs had less side effects on non-skeletal tissues.ConclusionsThis study presented a remote-controlled release system based on bone-targeted multifunctional NPs and a new potential approach to bone-targeted therapy of OP.

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Effect of Prostaglandin E2 on aqueous humor flow in the rabbit eye

Graefe s Archive for Clinical and Experimental Ophthalmology ◽

10.1007/bf00407096 ◽

1974 ◽

Vol 190 (3) ◽

pp. 221-227 ◽

Cited By ~ 3

Author(s):

Stephen Tak�ts ◽

Casimir Jobst ◽

Hilda Szilv�ssy

Keyword(s):

Prostaglandin E2 ◽

Aqueous Humor ◽

Rabbit Eye ◽

Aqueous Humor Flow

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Use of Municipal Solid Waste Incineration Bottom Ash in Adsorption of Heavy Metals

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.474-476.1099 ◽

2011 ◽

Vol 474-476 ◽

pp. 1099-1102

Author(s):

Hai Ying Zhang ◽

Yi Zheng ◽

Hong Tao Hu ◽

Jing Yu Qi

Keyword(s):

Heavy Metals ◽

Particle Size ◽

Municipal Solid Waste ◽

Solid Waste ◽

Residence Time ◽

Bottom Ash ◽

Waste Incineration ◽

Synthetic Wastewater ◽

High Porosity ◽

Municipal Solid Waste Incineration

Bottom ash from municipal solid waste incineration (MSWI) has been previously suggested as an adsorbent for removing heavy metals from wastewater due to its high porosity and large surface area. In this study the adsorption characteristics of heavy metals were investigated using various particle sizes of MSWI bottom ash. The adsorption experiment was conducted using synthetic wastewater containing Cu, Zn, Pb and Cd as a function of residence time, initial pH, ash dosage and particle size, respectively. The adsorption rate increased with decreasing particle size and with increasing residence time. Through the above analysis, this work proved that bottom ash was effective in adsorbing the four heavy metals.

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greater the probability that the particles will miss the high shear zones on a single pass through the device. For this reason the discharge of many rotor/stator devices is re-stricted with a series of holes or bars, or with a grid, which performs two separate tasks. First, a discharge grid absolutely limits the maximum particle size that can exit the mixer. If the holes on the discharge grid are 2 mm, it is virtually impossible for par-ticles larger than that diameter to pass through the machine. Rotor/stator in-line mix-ers are made with restricting grids as small as 0.5 mm, and a wide range of larger sizes up to 50 mm or even unrestricted outlets. A sample of such grids is presented in Fig. 29. But even the smallest usable discharge grid does not necessarily provide abso-lute control of the required size distributions in the range of fine dispersion. This is the second reason for the restriction on the discharge. By putting a more limiting dis-charge on the outlet, the flow rate through the device for a given set of pumping cir-cumstances (viscosity, density, system suction, and discharge head) is reduced and the residence time in the machine for a given particle or droplet is increased. The longer residence time increases the probability that a particle has to travel through the highest shearing zones and, thereby, be reduced to the smallest size that the machine is capable of producing. • • • • " ' ; • " * * «L £ J- •-

Pharmaceutical Dosage Forms ◽

10.1201/9781420000955-51 ◽

1998 ◽

pp. 358-360

Keyword(s):

Particle Size ◽

Residence Time ◽

Flow Rate ◽

Shear Zones ◽

High Shear ◽

Single Pass ◽

Fine Dispersion ◽

Wide Range ◽

Maximum Particle ◽

Pass Through

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Growth factor-like phospholipids generated after corneal injury

AJP Cell Physiology ◽

10.1152/ajpcell.1998.274.4.c1065 ◽

1998 ◽

Vol 274 (4) ◽

pp. C1065-C1074 ◽

Cited By ~ 77

Author(s):

Károly Liliom ◽

Zhiwei Guan ◽

Jih-Lie Tseng ◽

Dominic M. Desiderio ◽

Gábor Tigyi ◽

...

Keyword(s):

Mass Spectrometry ◽

Growth Factor ◽

Phosphatidic Acid ◽

Aqueous Humor ◽

Lysophosphatidic Acid ◽

Xenopus Oocyte ◽

Two Dimensional ◽

Corneal Injury ◽

Rabbit Eye ◽

Cellular Regeneration

The present study provides evidence that growth factor-like glycerophosphate mediators of the lysophosphatidic acid (LPA) family are present in the aqueous humor and the lacrimal gland fluid of the rabbit eye. By use of a combination of HPLC, two-dimensional TLC, mass spectrometry, and the Xenopus oocyte bioassay, the LPA-like phospholipids LPA, cyclic PA, alkenyl-glycerophosphate (GP), lysophosphatidylserine, and phosphatidic acid were detected as physiological constituents of the fluids bathing the cornea. Corneal injury resulted in an increased production of some of these mediators. Alkenyl-GP, a novel member of the LPA family, has been identified in postinjury aqueous humor, establishing that it is generated endogenously. LPA and its homologues were found to be mitogenic in freshly dissociated keratocytes from uninjured corneas. There appears to be a link between the occurrence of LPA responsiveness in keratocytes activated by injury and the increase in LPA-like activity in aqueous humor. These data suggest that LPA and its homologues are involved in maintaining the integrity of the normal cornea and in promoting cellular regeneration of the injured cornea.

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Preparation of All-Trans-Retinoic Acid-Loaded mPEG-PLGA Nanoparticles Using Microfluidic Flow-Focusing Device for Controlled Drug Delivery

NANO ◽

10.1142/s1793292020501015 ◽

2020 ◽

Vol 15 (08) ◽

pp. 2050101

Author(s):

Mojdeh Safari ◽

Amir Amani ◽

Tajudeen Adebileje ◽

Jafar Ai ◽

Seyed Mahdi Rezayat ◽

...

Keyword(s):

Particle Size ◽

Retinoic Acid ◽

Plga Nanoparticles ◽

Process Conditions ◽

Flow Focusing ◽

Flow Rates ◽

Trans Retinoic Acid ◽

All Trans Retinoic Acid ◽

Microfluidic Flow ◽

Minimum Particle Size

In recent years, microfluidic devices present unique advantages for the development of a new generation of nanoparticle synthesis method compared to bulk methods. In this study, we report a microfluidic flow-focusing method for the production of all trans retinoic acid (ATRA)-loaded methoxy poly(ethylene glycol)-poly(lactide-coglycolide) (mPEG-PLGA) nanoparticles (NPs). Box–Behnken experimental design (BBD) was applied to optimize of formulation ingredients and process conditions with minimum particle size, maximum drug loading% (DL%) and encapsulation efficiency% (EE%). Polymer concentration, drug concentration and flow rates of solvent (S) and antisolvent (AS) were selected as independent variables. Based on optimization strategy, minimum particle size achieved shows average (SD) particle size of [Formula: see text][Formula: see text]nm with DL of [Formula: see text][Formula: see text]wt.% and EE of [Formula: see text][Formula: see text]wt.%, respectively. While maximum DL has been reported to be [Formula: see text][Formula: see text]wt.% with particle size of [Formula: see text][Formula: see text]nm and EE of [Formula: see text][Formula: see text]wt.%, respectively. Moreover, the results have shown that the AS/S ratio represents the most significant effect on particle size. Indeed, increasing the AS flow rate directly results in generating smaller particles. The AS/S ratio represents the least significant effect on DL%, such that, at fixed flow rates, higher DL was observed at high concentration of drug and lower concentration of polymer. In conclusion, optimization of the ATRA-loaded mPEG-PLGA NPs by BBD yielded in a favorable drug carrier for ATRA that could provide a new treatment modality for different malignancies.

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Patterned nanofiber air filters with high optical transparency, robust mechanical strength, and effective PM2.5 capture capability

RSC Advances ◽

10.1039/d0ra01967d ◽

2020 ◽

Vol 10 (34) ◽

pp. 20155-20161 ◽

Cited By ~ 3

Author(s):

Jinshan Cao ◽

Zhiqiang Cheng ◽

Lijuan Kang ◽

Meng Lin ◽

Lihao Han

Keyword(s):

Particle Size ◽

Mechanical Strength ◽

Human Health ◽

Residence Time ◽

Small Particle ◽

Toxic Substances ◽

Small Particle Size ◽

Daily Production ◽

Air Filters ◽

Strong Activity

PM2.5, due to its small particle size, strong activity, ease of the attachment of toxic substances and long residence time in the atmosphere, has a great impact on human health and daily production.

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