Related Experiment Video
Updated: Jun 2, 2026
07:32
Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
Polymyxin B self-associated with phospholipid nanomicelles
Kenneth S Brandenburg1, Israel Rubinstein, Ruxana T Sadikot
1Department of Bioengineering, University of Illinois at Chicago, IL, USA.
Pharmaceutical Development and Technology
|April 14, 2011
Summary
Polymyxin B (PXB) antibiotic activity decreased when self-associated with PEGylated nanomicelles (SSM). This nanomedicine formation reduced PXB
Area of Science:
- Nanomedicine
- Pharmacology
- Microbiology
Background:
- Polymyxin B (PXB) is a crucial antibiotic for Gram-negative infections.
- Clinical use of PXB is limited by toxicity and protein binding.
- Nanocarrier delivery may overcome PXB limitations.
Purpose of the Study:
- To investigate PXB self-association with PEGylated phospholipid nanomicelles (SSM).
- To evaluate the in vitro bioactivity of PXB-loaded SSM.
Main Methods:
- PXB and SSM (15 nm) were prepared.
- Interactions were analyzed using dynamic light scattering and fluorescence spectroscopy.
- In vitro anti-infective effects were tested against Pseudomonas aeruginosa.
Main Results:
- Approximately four PXB molecules associated with each SSM.
- PXB-SSM showed significantly reduced killing of P. aeruginosa compared to PXB alone.
- Empty SSM did not affect bacterial growth.
Conclusions:
- PXB self-association with SSM mitigated in vitro antibacterial activity.
- PEGylation may hinder PXB's electrostatic interactions with bacterial cell walls.
- Further in vivo studies are needed to assess nanomedicine efficacy.
Related Concept Videos
01:23Inhibitors of Gram-positive Cell Wall Synthesis
Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...
01:24Site-Targeted Drug Delivery Systems: Polymeric Carriers
Polymeric carriers enhance targeted drug delivery by increasing efficacy while minimizing off-target effects. These carriers comprise a biodegradable polymeric backbone integrated with functional elements that enable targeting, improve physicochemical properties, and regulate drug release.Targeting MechanismsThe targeting ability of polymeric carriers is mediated by a homing device, which is a molecular recognition component designed to selectively bind to specific tissues or cells. Monoclonal...
01:30Micelles
Micelle formation is an intricate process that hinges on the properties of amphiphilic or amphipathic molecules and the conditions of the system in which they are found. Amphiphilic molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, play a critical role in this process.In aqueous environments, these molecules arrange themselves such that their hydrophilic heads are turned towards the water phase, while their hydrophobic tails are oriented away...