John Garner

PLGA from PolySciTech used for Herceptin targeted pH sensitive drug delivery to breast cancer

Blog Post created by John Garner on Aug 17, 2015

PolySciTech ( provides a wide array of the PLGA polymers including AP041 (PLGA 50:50 10-15kDa). A recent article by researchers at the University of Cincinnati used this PLGA as  a component to synthesize PLGA-pHis-PEG block copolymer for Herceptin mediated, pH sensitive drug delivery to breast cancer cells. Read more: Zhou, Zilan, Apurva Badkas, Max Stevenson, Joo-Youp Lee, and Yuet-Kin Leung. "Herceptin conjugated PLGA-PHis-PEG pH sensitive nanoparticles for targeted and controlled drug delivery." International journal of pharmaceutics 487, no. 1 (2015): 81-90.

“Abstract: A dual functional nano-scaled drug carrier, comprising of a targeting ligand and pH sensitivity, has been made in order to increase the specificity and efficacy of the drug delivery system. The nanoparticles are made of a tri-block copolymer, poly(d,l lactide-co-glycolide) (PLGA)-b-poly(l-histidine) (PHis)-b-polyethylene glycol (PEG), via nano-precipitation. To provide the nanoparticle feature of endolysosomal escape and pH sensitivity, poly(l-histidine) was chosen as a proton sponge polymer. Herceptin, which specifically binds to HER2 antigen, was conjugated to the nanoparticles through click chemistry. The nanoparticles were characterized via dynamic light scattering (DLS) and transmission electron microscopy (TEM). Both methods showed the sizes of about 100 nm with a uniform size distribution. The pH sensitivity was assessed by drug releases and size changes at different pH conditions. As pH decreased from 7.4 to 5.2, the drug release rate accelerated and the size significantly increased. During in vitro tests against human breast cancer cell lines, MCF-7 and SK-BR-3 showed significantly increased uptake for Herceptin-conjugated nanoparticles, as compared to non-targeted nanoparticles. Herceptin-conjugated pH-sensitive nanoparticles showed the highest therapeutic effect, and thus validated the efficacy of a combined approach of pH sensitivity and active targeting. Keywords: Polymeric nanoparticles; Breast cancer; Active targeting; pH sensitivity; Herceptin”



Zhou, 2015 Herceptin PLGA-pHis-PEG delivery.png