Injectable glycol chitosan thermogel formulation for efficient inner ear drug delivery

Hearing loss is one of the most common disabilities affecting both children and adults worldwide. However, traditional treatment of hearing loss has some limitations, particularly in terms of drug delivery system as well as diagnosis of ear imaging. The blood–labyrinth barrier (BLB), the barrier between the vasculature and fluids of the inner ear, restricts entry of most blood-borne compounds into inner ear tissues. Nanoparticles (NPs) have been demonstrated to have high biocompatibility, good degradation, and simple synthesis in the process of diagnosis and treatment, which are promising for medical applications in hearing loss. Although previous studies have shown that NPs have promising applications in the field of inner ear diseases, there is still a gap between biological research and clinical application. In this paper, we aim to summarize developments and challenges of NPs in diagnostics and treatment of hearing loss in recent years. This review may be useful to raise otology researchers’ awareness of effect of NPs on hearing diagnosis and treatment.

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A Totally Implantable Drug Delivery System for Local Therapy of the Middle and Inner Ear

Ear Nose & Throat Journal ◽

10.1177/014556139707600813 ◽

1997 ◽

Vol 76 (8) ◽

pp. 567-570 ◽

Cited By ~ 15

Author(s):

Rolf Lehner ◽

Heribert Brugger ◽

Marcus M. Maassen ◽

Hans-Peter Zenner

Keyword(s):

Drug Delivery ◽

Inner Ear ◽

Drug Delivery System ◽

Delivery System ◽

Drug Application ◽

Local Therapy ◽

Trophic Factors ◽

Mastoid Cavity ◽

Round Window Membrane ◽

Wide Range

Local therapy of middle and inner ear diseases is being used, but is restricted to cases of ear drum perforation or to repeated invasive intratympanic drug application by the physician. In accordance with the Medical Device Directive (class III), a bone-anchored, totally implantable drug delivery system (TI-DDS) has been developed. It includes a micropump for subcutaneous, patient-controlled activation, a drug reservoir and a septum port. A thin guide-wired catheter leads from the pump outlet to the point of application in the mastoid or middle ear cavities. Local inner ear therapy with suitable drugs is possible by positioning the catheter's end near the round window membrane. The system requires no battery and will offer a wide range of patient-controlled bolus applications (25 μl per activation). We first analyzed the three-dimensional implantation geometry of the mastoid cavity. Basic micromechanical problems have been solved in order to create several prototypes. The TI-DDS has already undergone extensive in vitro testing. Recent results of pump rate precision and digital pressure force testing are promising. Local drug treatment for conditions such as lidocaine-sensitive tinnitus, secretory otitis media, Meniere's disease, localized pain and intralesional cancer is under discussion. Furthermore, local application of future biotechnological trophic factors for inner ear treatment is anticipated. The basic engineering is completed and initial animal tests are in preparation.

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Mucoadhesive dexamethasone-glycol chitosan nanoparticles for ophthalmic drug delivery

International Journal of Pharmaceutics ◽

10.1016/j.ijpharm.2019.118943 ◽

2020 ◽

Vol 575 ◽

pp. 118943 ◽

Cited By ~ 10

Author(s):

Ailing Yu ◽

Hui Shi ◽

Hui Liu ◽

Zhishu Bao ◽

Mali Dai ◽

...

Keyword(s):

Drug Delivery ◽

Chitosan Nanoparticles ◽

Glycol Chitosan ◽

Ophthalmic Drug Delivery ◽

Ophthalmic Drug

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Polyethylene Glycol-Chitosan Oligosaccharide-Coated Superparamagnetic Iron Oxide Nanoparticles: A Novel Drug Delivery System for Curcumin Diglutaric Acid

Biomolecules ◽

10.3390/biom10010073 ◽

2020 ◽

Vol 10 (1) ◽

pp. 73 ◽

Cited By ~ 2

Author(s):

Feuangthit Niyamissara Sorasitthiyanukarn ◽

Chawanphat Muangnoi ◽

Wuttinont Thaweesest ◽

Pahweenvaj Ratnatilaka Na Bhuket ◽

Pongsakorn Jantaratana ◽

...

Keyword(s):

Drug Delivery ◽

Polyethylene Glycol ◽

Iron Oxide ◽

Zeta Potential ◽

Superparamagnetic Iron Oxide ◽

Oxide Nanoparticles ◽

Chitosan Oligosaccharide ◽

Glycol Chitosan ◽

Novel Drug Delivery System ◽

Novel Drug

Curcumin diglutaric acid-loaded polyethylene glycol-chitosan oligosaccharide-coated superparamagnetic iron oxide nanoparticles (CG-PEG-CSO-SPIONs) were fabricated by co-precipitation and optimized using a Box–Behnken statistical design in order to achieve the minimum size, optimal zeta potential (≥ ±20 mV), and maximum loading efficiency and capacity. The results demonstrated that CG-PEG-CSO-SPIONs prepared under the optimal condition were almost spherical in shape with a smooth surface, a diameter of 130 nm, zeta potential of 30.6 mV, loading efficiency of 83.3%, and loading capacity of 8.3%. The vibrating sample magnetometer results of the optimized CG-PEG-CSO-SPIONs showed a superparamagnetic behavior. Fourier transform infrared spectroscopy and X-ray diffraction analyses indicated that the CG physically interacted with PEG-CSO-SPIONs. In addition, the CG-PEG-CSO-SPIONs could be stored dry for up to 12 weeks or in aqueous solution for up to 4 days at either 4 °C or 25 °C with no loss of stability. The CG-PEG-CSO-SPIONs exhibited a sustained release profile up to 72 h under simulated physiological (pH 7.4) and tumor extracellular (pH 5.5) environments. Furthermore, the CG-PEG-CSO-SPIONs showed little non-specific protein binding in the simulated physiological environment. The CG-PEG-CSO-SPIONs enhanced the cellular uptake and cytotoxicity of CG against human colorectal adenocarcinoma HT-29 cells compared to free CG, and more CG was delivered to the cells after applying an external magnetic field. The overall results suggest that PEG-CSO-SPIONs have potential to be used as a novel drug delivery system for CG.

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