Fabrication techniques and cutting performance of micro-textured self-lubricating ceramic cutting tools by in-situ forming of Al2O3-TiC

Background:: Doxycycline (DOX) is used in treating a bacterial infection, especially for periodontitis treatment. Objective: To reduce irritation of DOX for subgingival administration and increase the chemical stability and against enzy-matic, the complex of α-cyclodextrin with DOX was prepared and loaded into injectable in situ forming implant based on PLGA. Methods:: FTIR, molecular docking studies, X-ray diffraction, and differential scanning calorimetry was performed to char-acterize the DOX/α-cyclodextrin complex. Finally, the in-vitro drug release and modeling, morphological properties, and cellular cytotoxic effects were also evaluated. Results:: The stability of DOX was improved with complex than pure DOX. The main advantage of the complex is the al-most complete release (96.31 ± 2.56 %) of the drug within 14 days of the implant, whereas in the formulation containing the pure DOX and the physical mixture the DOX with α-cyclodextrin release is reached to 70.18 ± 3.61 % and 77.03 ± 3.56 %, respectively. This trend is due to elevate of DOX stability in the DOX/ α-cyclodextrin complex form within PLGA implant that confirmed by the results of stability. Conclusion:: Our results were indicative that the formulation containing DOX/α-cyclodextrin complex was biocompatible and sustained-release with minimum initial burst release.

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Enhanced drug loading of in situ forming gels for oral mucositis pain control

International Journal of Pharmaceutics ◽

10.1016/j.ijpharm.2021.120225 ◽

2021 ◽

Vol 595 ◽

pp. 120225

Author(s):

Tingting Li ◽

Rajesh V. Lalla ◽

Diane J. Burgess

Keyword(s):

Oral Mucositis ◽

Pain Control ◽

Drug Loading ◽

In Situ Forming

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Poly(ethylene glycol)-b-poly(1,3-trimethylene carbonate) Copolymers for the Formulation of In Situ Forming Depot Long-Acting Injectables

Pharmaceutics ◽

10.3390/pharmaceutics13050605 ◽

2021 ◽

Vol 13 (5) ◽

pp. 605

Author(s):

Marie-Emérentienne Cagnon ◽

Silvio Curia ◽

Juliette Serindoux ◽

Jean-Manuel Cros ◽

Feifei Ng ◽

...

Keyword(s):

Ethylene Glycol ◽

Surface Erosion ◽

Sustained Delivery ◽

Trimethylene Carbonate ◽

Poly Ethylene Glycol ◽

In Situ Forming ◽

Poly Ethylene ◽

Long Acting

This article describes the utilization of (methoxy)poly(ethylene glycol)-b-poly(1,3-trimethylene carbonate) ((m)PEG–PTMC) diblock and triblock copolymers for the formulation of in situ forming depot long-acting injectables by solvent exchange. The results shown in this manuscript demonstrate that it is possible to achieve long-term drug deliveries from suspension formulations prepared with these copolymers, with release durations up to several months in vitro. The utilization of copolymers with different PEG and PTMC molecular weights affords to modulate the release profile and duration. A pharmacokinetic study in rats with meloxicam confirmed the feasibility of achieving at least 28 days of sustained delivery by using this technology while showing good local tolerability in the subcutaneous environment. The characterization of the depots at the end of the in vivo study suggests that the rapid phase exchange upon administration and the surface erosion of the resulting depots are driving the delivery kinetics from suspension formulations. Due to the widely accepted utilization of meloxicam as an analgesic drug for animal care, the results shown in this article are of special interest for the development of veterinary products aiming at a very long-term sustained delivery of this therapeutic molecule.

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Regeneration of critical-sized defects, in a goat model, using a dextrin-based hydrogel associated with granular synthetic bone substitute

Regenerative Biomaterials ◽

10.1093/rb/rbaa036 ◽

2020 ◽

Author(s):

Isabel Pereira ◽

José Eduardo Pereira ◽

Luís Maltez ◽

Alexandra Rodrigues ◽

Catarina Rodrigues ◽

...

Keyword(s):

Bone Regeneration ◽

Bone Substitute ◽

Bone Substitutes ◽

Multipotent Mesenchymal Stromal Cells ◽

Micro Computed Tomography ◽

Synthetic Bone Substitute ◽

In Situ Forming ◽

Bioactive Agents ◽

In Situ Forming Hydrogels

Abstract The development of injectable bone substitutes (IBS) have obtained great importance in the bone regeneration field, as a strategy to reach hardly accessible defects using minimally invasive techniques and able to fit to irregular topographies. In this scenario, the association of injectable hydrogels and bone graft granules is emerging as a well-established trend. Particularly, in situ forming hydrogels have arisen as a new IBS generation. An in situ forming and injectable dextrin-based hydrogel (HG) was developed, aiming to act as a carrier of granular bone substitutes and bioactive agents. In this work, the HG was associated to a granular bone substitute (Bonelike®) and implanted in goat critical-sized calvarial defects (14 mm) for 3, 6 and 12 weeks. The results showed that HG improved the handling properties of the Bonelike® granules and did not affect its osteoconductive features, neither impairing the bone regeneration process. Human multipotent mesenchymal stromal cells from the umbilical cord, extracellular matrix hydrolysates and the pro-angiogenic peptide LLKKK18 were also combined with the IBS. These bioactive agents did not enhance the new bone formation significantly under the conditions tested, according to micro-computed tomography and histological analysis.

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Impact of octreotide counterion nature on the long-term stability and release kinetics from an in situ forming depot technology

Journal of Controlled Release ◽

10.1016/j.jconrel.2021.06.044 ◽

2021 ◽

Vol 336 ◽

pp. 457-468

Author(s):

Charlotte Molinier ◽

Marina Picot-Groz ◽

Océane Malval ◽

Sophie Le Lamer-Déchamps ◽

Joël Richard ◽

...

Keyword(s):

Release Kinetics ◽

Term Stability ◽

Long Term Stability ◽

In Situ Forming ◽

Counterion Nature

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Chip formation and the interaction of mesoscopic geometric features of cutter

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211028469 ◽

2021 ◽

pp. 095440542110284

Author(s):

Xin Tong ◽

Yanxiang Ren ◽

Jianing Shen ◽

Song Yu

Keyword(s):

Synergistic Effect ◽

Prediction Models ◽

Cutting Tools ◽

Chip Morphology ◽

Orthogonal Test ◽

Cutting Performance ◽

Geometric Features ◽

High Quality ◽

Milling Tool ◽

Interaction Test

Most of the researches on the properties of micro-textured tools are based on an orthogonal test, while the interaction between micro-textured parameters is ignored. Therefore, this thesis is based on an interaction test to study the cutting performance of cutting tools. According to the chip morphology obtained from the interactive test, the micro texture diameter of 60 μm is obtained when the cutting is stable. It was also found that the synergistic effect of multiple mesoscopic geometric features had a significant influence on cutting performance. By analysis, we found the optimized parameters for the milling tool were D = 60 μm, l = 100 μm, l1 = 150 μm, r = 60 μm. Furthermore, prediction models of the cutting performance were established by univariate linear regression and the validity of these models was verified. Thus, this thesis provides a reference for improving the performance of cutting tools and for achieving efficient and high-quality machining of titanium alloys.

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In situ forming pluronic® F127/chitosan hydrogel limits metronidazole transmucosal absorption

European Journal of Pharmaceutics and Biopharmaceutics ◽

10.1016/j.ejpb.2016.11.024 ◽

2017 ◽

Vol 112 ◽

pp. 143-147 ◽

Cited By ~ 20

Author(s):

Sophia Malli ◽

Christian Bories ◽

Bénédicte Pradines ◽

Philippe M. Loiseau ◽

Gilles Ponchel ◽

...

Keyword(s):

Chitosan Hydrogel ◽

In Situ Forming

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Cutting Performance and Wear Mechanism of Si3N4-Based Nanocomposite Ceramic Tool

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.443.324 ◽

2010 ◽

Vol 443 ◽

pp. 324-329 ◽

Cited By ~ 1

Author(s):

Bin Zou ◽

Chuan Zhen Huang ◽

Han Lian Liu ◽

Jin Peng Song

Keyword(s):

Wear Resistance ◽

Wear Mechanism ◽

Cutting Tools ◽

Cutting Speed ◽

Cutting Performance ◽

Nano Particles ◽

Ceramic Tool ◽

Tool Materials ◽

High Cutting Speed ◽

The Matrix

Si3N4/TiN nanocomposite tool and Si3N4/Ti(C7N3) nanocomposite tool were prepared. The cutting performance and wear mechanism of Si3N4-based nanocomposite ceramic tool was investigated by comparison with a commercial sialon ceramic tool in machining of 45 steel. Si3N4-based nanocomposite ceramic tool exhibits the better wear resistance than sialon at the relatively high cutting speed. The increased cutting performance of Si3N4-based nanocomposite ceramic tool is ascribed to the higher mechanical properties. Nano-particles can refine the matrix grains and improve the bonding strength among the matrix grains of Si3N4-based nanocomposite ceramic tool materials. It contributes to an improved wear resistance of the cutting tools during machining.

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