Enzyme responsive amphiphiles
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Transcript of Enzyme responsive amphiphiles
Bionano Chemistry Lab
Muhammad Ehsan (2013652616)
Literature meeting
Date: 2014-05-02
dx.doi.org/10.1021/ja413036q | J. Am. Chem. Soc. XXXX, XXX, XXX−XXX
dx.doi.org/10.1021/ja413036q | J. Am. Chem. Soc. XXXX, XXX, XXX−XXX
Introduction
Stimuli-responsive micelles have gained increasing attention due to their potential utilization as nanocarriers for drug delivery.
Responsive materials are inspired
changes in pH, temperature, irradiated light, or their combination
Enzymes as stimuli
Encapsulation and release of hydrophobic guests
Figure . Schematic representation of the encapsulation of hydrophobic guests in the hydrophobic core of a smart micel-lar nanocarrier. Upon enzymatic cleavage of the hydrophobic end groups, the nanocarrier disassembles and the guest molecules are released.
Synthesis of Amphiphilic PEG-Dendron Hybrids
Self-Assemble into Micelles
Self-Assembled Structures
Figure S26: TEM micrographs of micelles formed from PEG-dendron
hybrids 1a-c.
Selectivity of the Enzymatic Activation
Figure : Fluorescence emission intensity of compound 1b is unaffected in the absence of the activating enzyme penicilin G amidase (PGA ) after 12 hours in buffer
Figure : Fluorescence emission intensity of compound 1b is unaf-fected in the presence of 0.66μM of Esterase from porcine liver (PLE enzyme) , which is not capable of breaking amide bond .
Micelle Disassembly with Nile Red Fluorescence
Figure . Fluorescence spectra of Nile red (1.25 μM) in the presenceof PEG-dendron hybrid 1b (160 μM) as a function of time after theaddition of the activating enzyme, PGA (0.14 μM). Fluorescenceintensity decreased as Nile red was released into solution.
Enzymatic Degradation of the PEG-Dendron Hybrids
Disassembly and Hydrolysis Rate
Hypothetical Enzymatic Activation Pathways
Summary
• New family of amphiphilic PEG-dendron hybrids.
• Enzyme-responsive hybrids and their self assembled micelles have great potential in the field of drug delivery.
• Disassembly and release rates depended on the CMC.