A modified hydrophobic ion-pairing complex strategy for long-term peptide delivery with high drug encapsulation and reduced burst release from PLGA microspheres

Tetramethylpyrazine (TMP), isolated from the rhizome of the traditional Chinese medicinal plant Chuanxiong (Ligusticum wallichii Franchat) shows therapeutic efficacy against osteoarthritis. After intra-articular injection, the retention time of TMP in the joint cavity is short, which limits its treatment effect. To avoid this problem, the present study explored the preparation of a TMP nanosuspension (TMP-NS) based on hydrophobic ion pairing. TMP-NS showed a particle size of approximately 588 nm and, after intra-articular injection in rats, it had longer retention in the articular cavity, higher TMP concentrations in joints, and greater anti-osteoarthritic efficacy than TMP solution. TMP-NS didn’t cause significant inflammation at the joint. These results suggest that TMP-NS may strengthen and prolong the therapeutic efficacy of TMP against osteoarthritis without systemic toxicity.

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Thermosensitive Hydrogel Incorporating Microspheres for Injectable Implant Delivery of Naltrexone

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.647.71 ◽

2013 ◽

Vol 647 ◽

pp. 71-79 ◽

Cited By ~ 2

Author(s):

Guo Qiang Jiang ◽

Yu Jie Wang ◽

Fu Xin Ding

Keyword(s):

Sol Gel ◽

High Water ◽

The Body ◽

High Water Content ◽

Burst Release ◽

Thermosensitive Hydrogel ◽

Sol Gel Transition ◽

Gel Transition

Long-term drug delivery based on the injectable thermosensitive hydrogel is of great advantage to the administration of naltrexone, but the constant release is hard to reach due to the sol-gel transition and the high water content of the hydrogel. The aim of the present study is to develop an injectable implant delivery system by the incorporation of microspheres into thermosensitive hydrogel for the long-term constant release of naltrexone. Naltrexone was loaded in PLGA microsphere dispersed in the methylcellulose based thermosensitive sol, which formed the hydrogel containing the naltrexone-loaded microspheres at the body temperature. The presence of microsphere in the hydrogel delayed the sol-gel transition slightly but enhanced the mechanical strength of the hydrogel significantly. The microspheres degradation in water diffusion dominated phase was decelerated when they were embed in the hydrogel. The in vitro naltrexone release from the microsphere/hydrogel system showed an over 60 days constant release with no significant burst release, and the drug release rate was in proportion to the microsphere concentration in the hydrogel.

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Demineralized Bone Matrix as a Carrier for Bone Morphogenetic Protein-2: Burst Release Combined with Long-Term Binding and Osteoinductive Activity Evaluated In Vitro and In Vivo

Tissue Engineering Part A ◽

10.1089/ten.tea.2017.0005 ◽

2017 ◽

Vol 23 (23-24) ◽

pp. 1321-1330 ◽

Cited By ~ 18

Author(s):

Elisabeth Huber ◽

Anne-Marie Pobloth ◽

Nicole Bormann ◽

Nicolai Kolarczik ◽

Katharina Schmidt-Bleek ◽

...

Keyword(s):

Bone Morphogenetic Protein ◽

Demineralized Bone Matrix ◽

Bone Matrix ◽

Bone Morphogenetic Protein 2 ◽

Burst Release ◽

Morphogenetic Protein ◽

Demineralized Bone

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Novel skin penetrating berberine oleate complex capitalizing on hydrophobic ion pairing approach

International Journal of Pharmaceutics ◽

10.1016/j.ijpharm.2018.07.051 ◽

2018 ◽

Vol 549 (1-2) ◽

pp. 76-86 ◽

Cited By ~ 12

Author(s):

Abrar S. Torky ◽

May S. Freag ◽

Maha M.A. Nasra ◽

Ossama Y. Abdallah

Keyword(s):

Ion Pairing ◽

Hydrophobic Ion Pairing

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Development of an antimicrobial peptide-loaded mineralized collagen bone scaffold for infective bone defect repair

Regenerative Biomaterials ◽

10.1093/rb/rbaa015 ◽

2020 ◽

Vol 7 (5) ◽

pp. 515-525

Author(s):

Yuzhu He ◽

Yahui Jin ◽

Xiaoxia Ying ◽

Qiong Wu ◽

Shenglian Yao ◽

...

Keyword(s):

Antibacterial Properties ◽

Clinical Work ◽

Bone Defects ◽

Mechanical Tests ◽

Great Promise ◽

Plga Microspheres ◽

Bone Scaffold ◽

Defect Repair ◽

Mineralized Collagen

Abstract The repair of infective bone defects is a great challenge in clinical work. It is of vital importance to develop a kind of bone scaffold with good osteogenic properties and long-term antibacterial activity for local anti-infection and bone regeneration. A porous mineralized collagen (MC) scaffold containing poly(d,l-lactide-co-glycolic acid) (PLGA) microspheres loaded with two antibacterial synthetic peptides, Pac-525 or KSL-W was developed and characterized via scanning electron microscopy (SEM), porosity measurement, swelling and mechanical tests. The results showed that the MC scaffold embedded with smooth and compact PLGA microspheres had a positive effect on cell growth and also had antibacterial properties. Through toxicity analysis, cell morphology and proliferation analysis and alkaline phosphatase evaluation, the antibacterial scaffolds showed excellent biocompatibility and osteogenic activity. The antibacterial property evaluated with Staphylococcus aureus and Escherichia coli suggested that the sustained release of Pac-525 or KSL-W from the scaffolds could inhibit the bacterial growth aforementioned in the long term. Our results suggest that the antimicrobial peptides-loaded MC bone scaffold has good antibacterial and osteogenic activities, thus providing a great promise for the treatment of infective bone defects.

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Investigation of Various Cross-Linking Methods for the Immobilization of Cytosine Arabinoside on Bacterial Magnetosomes

Journal of Nanomaterials ◽

10.1155/2017/6738484 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Qinglei Dai ◽

Yiming Ma ◽

Shibin Wang ◽

Ranjith Kumar Kankala ◽

Yuangang Liu

Keyword(s):

Cytosine Arabinoside ◽

Iron Sulfide ◽

Lipid Membrane ◽

Drug Loading ◽

Burst Release ◽

Direct Absorption ◽

Drug Delivery Vehicles ◽

Delivery Vehicles ◽

Natural Lipid

Bacterial magnetosomes (BMs) have emerged as potential drug delivery vehicles, possessing an iron oxide or iron sulfide core surrounded by a natural lipid membrane shell. In this study, we immobilized cytosine arabinoside (Ara-C) effectively on BMs by using various methods such as direct absorption (ABMs), and others include different cross-linkers such as genipin (GP) and glutaraldehyde (G). A well-dispersed Ara-C coupled bacterial magnetosomes resulted in significantly higher negative charge than that of naked BMs (−11.5±0.3 mV) confirming the drug loading. Out of all methods, direct absorption process led to the highest encapsulation efficiency and drug loading of88.2±4.3% and46.9±1.2%, respectively. These designs have shown the long-term drug release behavior without an initial burst release. Our results indicate that BMs-based nanoconjugates will potentially find widespread applications in pharmaceutical field.

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