mPEG-PLGA MRSA polyscitech 2017.jpg

MRSA is a bacterial infection that is highly resistant to conventional antibiotic treatments or other therapies. It is still affected by vancomycin, but the bacterial spores have the capability to ‘hide’ inside of cells making it very difficult to treat. One means around this is to use nanoparticles for delivery of the antibiotic to the cells to ensure suitable vancomycin in a local concentration to kill off the bacteria. Recently, researchers at Purdue University used mPEG-PLGA (Polyvivo AK030) and rhodamine-B labelled PLGA (PolyVivo AV011) from PolySciTech ( to create pH sensitive nanoparticles designed for intracellular delivery of vancomycin. This research holds promise to improve treatments of this deadly bacterial infection. Read more: Pei, Yihua, Mohamed F. Mohamed, Mohamed N. Seleem, and Yoon Yeo. "Particle engineering for intracellular delivery of vancomycin to methicillin-resistant Staphylococcus aureus (MRSA)-infected macrophages." Journal of Controlled Release (2017).


“Abstract: Methicillin-resistant Staphylococcus aureus (MRSA) infection is a serious threat to the public health. MRSA is particularly difficult to treat when it invades host cells and survive inside the cells. Although vancomycin is active against MRSA, it does not effectively kill intracellular MRSA due to the molecular size and polarity that limit its cellular uptake. To overcome poor intracellular delivery of vancomycin, we developed a particle formulation (PpZEV) based on a blend of polymers with distinct functions: poly(lactic-co-glycolic acid) (PLGA, P) serving as the main delivery platform, (ii) polyethylene glycol-PLGA conjugate (PEG-PLGA, p) to help maintain an appropriate level of polarity for timely release of vancomycin, (iii) Eudragit E100 (a copolymer based on dimethylaminoethyl methacrylate, butyl methacrylate and methyl methacrylate, E) to enhance vancomycin encapsulation, and (iv) a chitosan derivative called ZWC (Z) to trigger pH-sensitive drug release. PpZEV NPs were preferentially taken up by the macrophages due to its size (500–1000 nm) and facilitated vancomycin delivery to the intracellular pathogens. Accordingly, PpZEV NPs showed better antimicrobial activity than free vancomycin against intracellular MRSA and other intracellular pathogens. When administered intravenously, PpZEV NPs rapidly accumulated in the liver and spleen, the target organs of intracellular infection. Therefore, PpZEV NPs is a promising carrier of vancomycin for the treatment of intracellular MRSA infection. Keywords: Nanoparticles, Intracellular drug delivery, pH-sensitive, Macrophages, Intracellular MRSA, Vancomycin”