A Multi‐crosslinking Nanocapsule‐Based Serial‐Stimuli‐Responsive Leakage‐Free Drug‐Delivery System In Vitro

2019 ◽  
Vol 25 (56) ◽  
pp. 13017-13024
Author(s):  
Yazhou Liu ◽  
Tianjiao Shen ◽  
Congcong Gao ◽  
H. A. Abdulhadi El‐Ali ◽  
Na Gao ◽  
...  
2018 ◽  
Vol 33 (2) ◽  
pp. 170-181 ◽  
Author(s):  
Hongying Su ◽  
Wen Zhang ◽  
Yayun Wu ◽  
Xiaodong Han ◽  
Gang Liu ◽  
...  

Stimuli-responsive hydrogels have been widely researched as carrier systems, due to their excellent biocompatibility and responsiveness to external physiologic environment factors. In this study, dextran-based nanogel with covalently conjugated doxorubicin (DOX) was developed via Schiff base formation using the inverse microemulsion technique. Since the Schiff base linkages are acid-sensitive, drug release profile of the DOX-loaded nanogel would be pH-dependent. In vitro drug release studies confirmed that DOX was released much faster under acidic condition (pH 2.0, 5.0) than that at pH 7.4. Approximately 66, 28, and 9% of drug was released in 72 h at pH 2.0, 5.0, and 7.4, respectively. Cell uptake by the human breast cancer cell (MCF-7) demonstrated that the DOX-loaded dextran nanogel could be internalized through endocytosis and distributed in endocytic compartments inside tumor cells. These results indicated that the Schiff base-containing nanogel can serve as a pH-sensitive drug delivery system. And the presence of multiple aldehyde groups on the nanogel are available for further conjugations of targeting ligands or imaging probes.


Biosensors ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 306
Author(s):  
Xin Xing ◽  
Zhijun Guo ◽  
Yue Su ◽  
Zhen Yang ◽  
Jiwen Qian ◽  
...  

Owing to poor aqueous solubility and low delivery efficiency, most of anti-cancer chemodrugs depend on various smart drug delivery platforms to enhance the treatment efficacy. Herein, a stimuli-responsive supramolecular drug delivery system (SDDS) is developed based on polymeric cyclodextrins (PCD) which crosslinked by stimuli-cleavable drug dimers via host-guest interaction. PEGylated PCD was precisely controlled synthesized by ring-opening polymerization and azide-alkyne click chemistry, and two doxorubicins (DOX) were linked with a disulfide bond to form a drug dimer (ss-DOX). They then co-assembled into supramolecular micelles. Drug dimers were utilized as cross-linkers to stabilize the micelles. The drug loading efficiency was very high that could be up to 98%. The size and morphology were measured by DLS and TEM. Owing to the disulfide bonds of drug dimers, these supramolecular micelles were dissociated by treating with dithiothreitol (DTT). In the meanwhile, the free DOXs were recovered and released from cavities of cyclodextrins because of dynamic equilibrium and hydrophilicity changes. The release profile was studied under mimic physiological conditions. Furthermore, in vitro cytotoxicity study showed excellent anti-cancer efficacy of reduced-responsive supramolecular polymeric micelles. Therefore, it can be served as a safe and stimuli-responsive SDDS for cancer therapy.


2015 ◽  
Vol 7 (1-2) ◽  
pp. 65-74
Author(s):  
K. Latha ◽  
V. V. Srikanth ◽  
S. A. Sunil ◽  
N. R. Srinivasa ◽  
M. U. Uhumwangho ◽  
...  

The objective of this investigation is to study the applicability of gum karaya, the natural gum for the preparation and in vitro evaluation of losartan potassium, as Chronotherapeutic Drug Delivery System (ChDDS). The compression-coated timed-release tablets (CCT) containing losartan potassium in the core tablet were prepared by dry coating technique with different ratios of gum karaya as the outer coat. The parameters investigated were tensile strength, friability, in vitro dissolution studies and drug concentration. The optimized formulation was further characterized by powder XRD and FTIR to investigate interactions and no interactions observed. The tensile strength and friability of all the CCT were between 1.06-1.23 MN/m2 and < 0.3% respectively.  All the CCT showed a clear lag time before a burst release of drug. However, the lag time of drug release increased as the amount of gum karaya in the outer layer increased. For instance, the lag time of LGK1, LGK2, LGK3, LGK4, LGK5, LGK6 and LGK7 were 16, 10.5, 5.5, 3, 2, 1.5 and 0.5 hrs respectively.  The drug content of all the CCT was >98%. Formulation LGK3 was taken as an optimized formulation which can be exploited to achieve ChDDS of losartan potassium for the treatment of hypertension. 


2003 ◽  
Vol 92 (12) ◽  
pp. 2411-2418 ◽  
Author(s):  
Neslihan Gursoy ◽  
Jean‐Sebastien Garrigue ◽  
Alain Razafindratsita ◽  
Gregory Lambert ◽  
Simon Benita ◽  
...  

2007 ◽  
Vol 25 (6) ◽  
pp. 1347-1354 ◽  
Author(s):  
Heiko Kranz ◽  
Erol Yilmaz ◽  
Gayle A. Brazeau ◽  
Roland Bodmeier

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