Monthly Archives: March 2017

PLGA from PolySciTech used for development of NIR fluorescent dye delivery carrier to make tumors detectable through skin as a diagnostic aid

Near-infrared (NIR) is a frequency of light just outside of the range of human vision which can be seen through human flesh. The delivery of NIR fluorophores to cancer cells and other diseased tissues can provide for the opportunity to render cancer detectable through the skin by NIR fluorescent techniques. Recently, researchers at Wroclaw University (Poland) used PLGA from PolySciTech (PolyVivo AP062) to stabilize NIR active NaYF4:Er3+,Yb3 nanoparticles in a double emulsion along with nonionic surfactants. This research holds promise for allowing for improved cancer diagnostics by making tumors visible through the skin. Read more: Bazylińska, Urszula, and Dominika Wawrzyńczyk. “Encapsulation of TOPO stabilized NaYF 4: Er 3+, Yb 3+ nanoparticles in biocompatible nanocarriers: synthesis, optical properties and colloidal stability.” Colloids and Surfaces A: Physicochemical and Engineering Aspects (2017).

“Abstract: The emulsification process leading to up-converting NaYF4:Er3+,Yb3+ NPs encapsulation, was performed using a modified water/oil/water double emulsion evaporation method, where poly(lactic-co-glycolic acid) was used as biocompatible polymer. Span 80 and Cremophor A25 were applied as non-ionic surfactants and dichloromethane as oily phase. The use of trioctylphosphine oxide ligands for the synthesis of up-converting NaYF4:Er3+,Yb3+ NPs allowed to obtain spherical particles with sizes below 10 nm, what further facilitated the efficient encapsulation process. Those newly designed nanosystems were subjected to analysis of their morphology, colloidal stability and optical properties by: dynamic light scattering, ζ-potential, atomic force microscopy, transmission electron microscopy and measuring the up-conversion emission spectra of free and loaded NaYF4:Er3+,Yb3+ NPs. The encapsulated NaYF4:Er3+,Yb3+ NPs showed increased colloidal stability for a long period of 60 days of storage in different conditions. Simultaneously, the encapsulation process did not significantly influenced their optical properties and strong visible emission could be observed upon nearinfrared excitation. Highlights: NaYF4:Er,Yb NPs ∼5 nm in size were synthesized with TOPO used as a stabilizing ligands. The modified double emulsion evaporation method was successful in the up-converting NPs encapsulation. PLGA, Span 80 and Cremophor A25 act as the obtained nanosystems stabilizers. The encapsulation process retain the optical properties of NaYF4:Er3+,Yb3+ NPs. The obtained nanocarriers have potential applications as theranostic agents.”

mPEG-PCL from PolySciTech utilized in development of Chrysin-nanoparticle based therapy for lung-cancer

Lung cancer is among the leading causes of cancer-related death worldwide. Chrysin, a natural active flavone, acts to enhance the chemotherapeutic effectiveness of other chemoagents (cisplatin, docetaxel, etc.) against lung cancer. Chrysin’s usability, however, is limited by its very poor water solubility and low bioavailability. Recently, researchers at Duksung Women’s University (Korea) utilized mPEG-PCL from PolySciTech ( (PolyVivo #: AK001) to formulate chrysin-loaded nanoparticles which were found to delay tumor progression in a mouse model. This research holds promised for improved lung-cancer therapy. Read more: Kim, Kyoung Mee, Hyun Kyung Lim, Sang Hee Shim, and Joohee Jung. “Improved chemotherapeutic efficacy of injectable chrysin encapsulated by copolymer nanoparticles.” International Journal of Nanomedicine 12 (2017): 1917.

“Abstract: Chrysin is a flavone that is found in several plants and in honeycomb and possesses various biological activities. However, its low solubility means it has poor bioavailability, which must be resolved to enable its pharmaceutical applications. In the present study, chrysin was incorporated into methoxy poly(ethylene glycol)-β-polycaprolactone nanoparticles (chrysin-NPs) using the oil-in-water technique in order to overcome problems associated with chrysin. The properties of chrysin-NPs were analyzed, and their anticancer effects were investigated in vitro and in vivo. Chrysin-NPs were 77 nm sized (as determined by dynamic laser light scattering) and showed a monodisperse distribution. The zeta potential of chrysin-NPs was −2.22 mV, and they were spherically shaped by cryo-transmission electron microscopy (cryo-TEM). The loading efficiency of chrysin-NPs was 46.96%. Chrysin-NPs retained the cytotoxicity of chrysin in A549 cells. The therapeutic efficacies of chrysin-NPs were compared with those of chrysin in an A549-derived xenograft mouse model. Chrysin-NPs were intravenously injected at a 10 times lower dosage than chrysin 3 times per week (q2d×3/week). However, free chrysin was orally administrated 5 times per week (q1d×5/week). Chrysin-NP-treated group showed significant tumor growth delay, which was similar to that of chrysin-treated group, despite the considerably lower total dosage. These results suggest that the injectable chrysin-NPs enhance therapeutic efficacy in vivo and offer a beneficial formulation for chemotherapy. Keywords: chrysin, nanoparticle, chemotherapeutic efficacy, non-small-cell lung cancer, in vivo model. Nanoparticle preparation method: Chrysin (Sigma-Aldrich, St Louis, MO, USA) was incorporated into copolymer NPs using an oil-in-water technique (Figure 1). mPEG–β-polycaprolactone copolymer (mPEG-PCL, 50 mg; 2,000:5,200 Da; PolySciTech, West Lafayette, IN, USA) and 5 mg of chrysin were dissolved in a dichloromethane (Duksan reagent, Gyeonggi-do, Korea) and methanol mixture (Duksan reagent; v/v, 1.5:1). This solution (2.5 mL) was added to a 1% aqueous polyvinyl alcohol solution (6 mL) and was emulsified by sonification for 1 min. The solvent was removed by evaporation under stirring to produce NPs. To remove polyvinyl alcohol and surplus free chrysin, the supernatant was collected after centrifugation (14,000 rpm) twice at room temperature for 1 h.”

PLGA from PolySciTech used in optimizing 3D printing techniques for tissue engineering

A relatively recent and powerful tool for both manufacturing and research has been developed in 3D printing. Despite it’s advantages, 3D printing is restricted based on the polymeric material’s melt and processing properties. Recently, researchers working jointly at University of Maryland, Cornell University, and Rice University screened through a series of PLGA materials in order to define the optimal printing procedures for each. The utilized a series of PLGA’s from PolySciTech ( (PolyVivo AP039, AP137, AP076, and AP024) and optimized their printing configurations for bone-tissue engineering. This research holds promise for the capability to print biocompatible, biodegradable parts for tissue engineering and other applications. Read more at: Guo, Ting, Timothy Holzberg, Casey Lim, Feng Gao, Ankit Gargava, Jordan Trachtenberg, Antonios Mikos, and John Fisher. “3D printing PLGA: a quantitative examination of the effects of polymer composition and printing parameters on print resolution.” Biofabrication (2017).

“Abstract: In the past few decades, 3D printing has played a significant role in fabricating scaffolds with consistent, complex structure that meets patient-specific needs in future clinical applications. Although many studies have contributed to this emerging field of additive manufacturing, which includes material development and computer-aided scaffold design, current quantitative analyses do not correlate material properties, printing parameters, and printing outcomes to a great extent. A model that correlates these properties has tremendous potential to standardize 3D printing for tissue engineering and biomaterial science. In this study, we printed poly(lactic-co-glycolic acid) (PLGA) utilizing a direct melt extrusion technique without additional ingredients. We investigated PLGA with various lactic acid:glycolic acid (LA:GA) molecular weight ratios and end caps to demonstrate the dependence of the extrusion process on the polymer composition. Micro-computed tomography (microCT) was then used to evaluate printed scaffolds containing different LA:GA ratios, composed of different fiber patterns, and processed under different printing conditions. We built a statistical model to reveal the correlation and predominant factors that determine printing precision. Our model showed a strong linear relationship between the actual and predicted precision under different combinations of printing conditions and material compositions. This quantitative examination establishes a significant foreground to 3D print biomaterials following a systematic fabrication procedure. Additionally, our proposed statistical models can be applied to couple specific biomaterials and 3D printing applications for patient implants with particular requirements.”

PLGA-PEG-COOH from PolySciTech used in development of ultra-sound triggered breast cancer theranostic nanoparticles

One of the goals within controlled delivery is to provide for targeted medicinal delivery in which the medicine is guided to the site that it is needed in by natural processes. More specifically, in cancer, there is a need to delivery nanoparticles to the tumor site for both therapy (medicinal delivery) as well as diagnosis (contrast agent delivery). Recently, researchers at Chongqing Medical University (China) used PolySciTech ( product PLGA-PEG-COOH (PolyVivo AI056) and conjugated on Herceptin (antibody which conjugates to breast cancer tumors) to target it towards breast cancer cells. They formulated these with both contrast agents and chemotherapeutic paclitaxel. This research holds promise for improved breast-cancer therapy. Read more: Song, Weixiang, Yindeng Luo, Yajing Zhao, Xinjie Liu, Jiannong Zhao, Jie Luo, Qunxia Zhang, Haitao Ran, Zhigang Wang, and Dajing Guo. “Magnetic nanobubbles with potential for targeted drug delivery and trimodal imaging in breast cancer: an in vitro study.” Nanomedicine 0 (2017).

“Aim: The aim of this study was to improve tumor-targeted therapy for breast cancer by designing magnetic nanobubbles with the potential for targeted drug delivery and multimodal imaging. Materials & methods: Herceptin-decorated and ultrasmall superparamagnetic iron oxide (USPIO)/paclitaxel (PTX)-embedded nanobubbles (PTX-USPIO-HER-NBs) were manufactured by combining a modified double-emulsion evaporation process with carbodiimide technique. PTX-USPIO-HER-NBs were examined for characterization, specific cell-targeting ability and multimodal imaging. Results: PTX-USPIO-HER-NBs exhibited excellent entrapment efficiency of Herceptin/PTX/USPIO and showed greater cytotoxic effects than other delivery platforms. Low-frequency ultrasound triggered accelerated PTX release. Moreover, the magnetic nanobubbles were able to enhance ultrasound, magnetic resonance and photoacoustics trimodal imaging. Conclusion: These results suggest that PTX-USPIO-HER-NBs have potential as a multimodal contrast agent and as a system for ultrasound-triggered drug release in breast cancer.”

PolySciTech mPEG-PLGA and PLGA-Rhodamine products used in development of advanced chemoradiotherapy delivery system

Chemoradiotherapy is a cancer therapy technique in which a sensitizer molecule is administered to a patient prior to administration of a dose of radiation. Typically, such a technique is made difficult as the sensitizer molecule can affect both tumor tissue and normal tissue, causing more damage from radiation. However, with the application of localized-delivery to the tumor, this technique holds great potential for cancer therapy by allowing specific and selective destruction of tumor tissue at a relatively lower dose of radiation.  Recently, researchers at the University of North Carolina Chapel Hill utilized PolySciTech ( mPEG-PLGA’s (PolyVivo AK010, AK023) and fluorescently-tagged polymer PLGA-rhodamine B (PolyVivo AV011) for development of an advanced nanoparticle delivery system for Wortmannin (DNA-PK inhibitor) or novel KU60019 (ATM inhibitor) molecules. Both of these molecules act to increase local radiation damage to tumors by preventing DNA repair. The researchers found that smaller particles were more effective at avoiding hepatic clearance but medium sized particles showed more efficacy for sensitization. This research holds promise for enhanced cancer treatment techniques. Read more: Caster, Joseph M., K. Yu Stephanie, Artish N. Patel, Nicole J. Newman, Zachary J. Lee, Samuel B. Warner, Kyle T. Wagner et al. “Effect of particle size on the biodistribution, toxicity, and efficacy of drug-loaded polymeric nanoparticles in chemoradiotherapy.” Nanomedicine: Nanotechnology, Biology and Medicine (2017).

“Abstract: Nanoparticle (NP) therapeutics can improve the therapeutic index of chemoradiotherapy (CRT). However, the effect of NP physical properties, such particle size, on CRT is unknown. To address this, we examined the effects of NP size on biodistribution, efficacy and toxicity in CRT. PEG-PLGA NPs (50, 100, 150 nm mean diameters) encapsulating wotrmannin (wtmn) or KU50019 were formulated. These NP formulations were potent radiosensitizers in vitro in HT29, SW480, and lovo rectal cancer lines. In vivo, the smallest particles avoided hepatic and splenic accumulation while more homogeneously penetrating tumor xenografts than larger particles. However, smaller particles were no more effective in vivo. Instead, there was a trend towards enhanced efficacy with medium sized NPs. The smallest KU60019 particles caused more small bowel toxicity than larger particles. Our results showed that particle size significantly affects nanotherapeutics’ biodistrubtion and toxicity but does not support the conclusion that smaller particles are better for this clinical application. Graphical Abstract: Sub50 nm drug-loaded NPs avoid hepatic clearance and more homogeneously distribute within tumors. However, they are no more efficacious and are associated with more small bowel toxicity than larger particles. Keywords: Nanoparticle; Chemoradiotherapy; Nanoparticle radiosensitization; KU60019; Wortmannin”

Parkinson’s disease treatment developed using mPEG-PLGA block copolymer for neuroprotective agent delivery

Parkinson’s disease is a chronic, neural-degenerative which affects motor control and other operations of the nervous system eventually leading to death. Schisantherin A is a recently discovered neuroprotective agent which acts to inhibit damage to neural cells and can be used to slow the progression of Parkinson’s disease ( It has severe limitations, however, as it is poorly soluble in water and quickly cleared from the blood-stream.  Schisantherin A , like many neurological medicines, also faces the severe impediment of the blood-brain-barrier. This barrier which exists between circulating blood and brain tissue is intended to protect the brain from any toxic components that may be in the blood but also serves the unintentional purpose of preventing uptake of medicinal components into the brain tissue.  Recently, researchers at University of North Carolina at Chapel Hill and University of Macau utilized mPEG-PLGA to generate small-sized nanoparticles containing Schisantherin A. They found these nanoparticles to improve serum circulation longevity and uptake across the blood-brain-barrier. This research holds promise for enhanced therapy against this fatal disease. Similar block copolymers can be purchased from PolySciTech division of Akina, Inc. ( Read more about this exciting research here: Chen, Tongkai, Chuwen Li, Ye Li, Xiang Yi, Ruibing Wang, Simon Ming-Yuen Lee, and Ying Zheng. “Small-Sized mPEG–PLGA Nanoparticles of Schisantherin A with Sustained Release for Enhanced Brain Uptake and Anti-Parkinsonian Activity.” ACS Applied Materials & Interfaces (2017).

“Schisantherin A (SA) is a promising anti-Parkinsonism natural product. However, its poor water solubility and rapid serum clearance impose significant barriers to delivery of SA to the brain. This work aimed to develop SA in a nanoparticle formulation that extended SA circulation in the bloodstream and consequently an increased brain uptake and thus to be potentially efficacious for the treatment of Parkinson’s disease (PD). Spherical SA nanoparticles with a mean particle size of 70 nm were prepared by encapsulating SA into methoxy poly(ethylene glycol)-block-poly(d,l)-lactic-co-glycolic acid (mPEG–PLGA) nanoparticles (SA-NPs) with an encapsulation efficiency of ∼91% and drug loading of ∼28%. The in vitro release of the SA-NPs lasted for 48 h with a sustained-release pattern. Using the Madin–Darby canine kidney (MDCK) cell model, the results showed that first intact nanoparticles carrying hydrophobic dyes were internalized into cells, then the dyes were slowly released within the cells, and last both nanoparticles and free dyes were externalized to the basolateral side of the cell monolayer. Fluorescence resonance energy transfer (FRET) imaging in zebrafish suggested that nanoparticles were gradually dissociated in vivo with time, and nanoparticles maintained intact in the intestine and brain at 2 h post-treatment. When SA-NPs were orally administrated to rats, much higher Cmax and AUC0-t were observed in the plasma than those of the SA suspension. Furthermore, brain delivery of SA was much more effective with SA-NPs than with SA suspension. In addition, the SA-NPs exerted strong neuroprotective effects in zebrafish and cell culture models of PD. The protective effect was partially mediated by the activation of the protein kinase B (Akt)/glycogen synthase kinase-3β (Gsk3β) pathway. In summary, this study provides evidence that small-sized mPEG–PLGA nanoparticles may improve cross-barrier transportation, oral bioavailability, brain uptake, and bioactivity of this Biopharmaceutics Classification System (BCS) Class II compound, SA. Keywords: brain delivery; cellular uptake; fluorescence resonance energy transfer (FRET); mPEG−PLGA nanoparticles; oral bioavailability; Schisantherin A”

PLGA from PolySciTech investigated for use as adjuvant in Streptococcus vaccine development

Group A Strep is highly virulent and can be deadly without proper treatment. One means to reduce Strep infections is to apply nanoparticles presenting certain portions of the bacteria’s M-protein marker to elicit an immune response against Strep. Recently, researchers at The University of Queensland and Griffith University (Australia) utilized PolySciTech ( PLGA (PolyVivo AP041) to develop a nanoparticle vaccine against strep. They utilized PLGA as well as poly(lysine) and dextran to make these nanoparticles and found a substantially higher immune response against the PLGA likely due to its negative charge. This research holds promise for the development of an effective vaccine against Strep. Read more:  Marasini, Nirmal, Ashwini Kumar Giddam, Michael R. Batzloff, Michael F. Good, Mariusz Skwarczynski, and Istvan Toth. “Poly-L-lysine-coated nanoparticles are ineffective in inducing mucosal immunity against group a streptococcus.” (2017).

“Abstract Background: Group A Streptococcus (GAS) can cause a range of maladies, from simple throat infections to lethal complication, such as rheumatic heart disease. The M-protein, a bacterial cell surface protein, is the major virulence factor of GAS. Several attempts have been made over the past few decades to develop vaccines against GAS that employed peptides derived from the M-protein. One such approach used lipopeptides or lipid core peptide (LCP) systems that incorporated a B-cell epitope derived from the conserved region of the M-protein. Methods: In the present study, we prepared different biodegradable polymer [dextran, poly-(lactic- coglycolic-acid) (PLGA), and poly-L-lysine] nanoparticles (NPs)-based delivery systems for a lipopeptide vaccine candidate (LCP-1).The NPs were characterized by their size, charge, morphology, antigen-presenting cells (APCs) uptake and subsequent APCs maturations efficacy, followed by in vivo nasal immunization in mice. Results: All produced NPs ranged in size from 100-205 nm, and their charge varied depending upon the nature of polymer. A high APCs uptake efficacy for dextran and poly-L-lysine NPswere observed, compared to PLGA NPs. Despite the high uptake by APCs, dextran and poly-L-lysine NPs failed to improve APCs maturation that resulted in low antibody titres. In contrast, while LCP-1 encapsulated into PLGA showed low APCs uptake, it induced significant maturation of DCs and higher antibody titres compared to other NPs. Conclusions: Positively-charged poly-L-lysine NPs were non-immunogenic, while negatively charged PLGA NPs induced similar responses to antigens adjuvanted with cholera toxin B (CTB). Keywords: Mucosal delivery, lipopeptides, nanoparticles, nasal, vaccine, PLGA, Poly-L-lysine”

PLGA-PEG-Maleimide from PolySciTech used in development of macular degeneration treatment

One of the causes of ocular damage which can lead to blindness is choroidal neovascularization, effectively the over-growth of new blood vessels in the back of the eye. This condition is involved in the development of age-related macular degeneration which can lead to blindness. Recently, researchers at Yantai University (China) utilized Mal-PEG-PLGA (PolyVivo AI020) from PolySciTech ( to develop RGD and TAT peptide modified nanoparticles to deliver therapeutics to ocular tissues as part of treatment of macular degeneration. This research holds promise to provide treatment for a disease which causes blindness. Read more: Chu, Yongchao, Ning Chen, Huajun Yu, Hongjie Mu, Bin He, Hongchen Hua, Aiping Wang, and Kaoxiang Sun. “Topical ocular delivery to laser-induced choroidal neovascularization by dual internalizing RGD and TAT peptide-modified nanoparticles.” International Journal of Nanomedicine 12 (2017): 1353.

“Abstract: A nanoparticle (NP) was developed to target choroidal neovascularization (CNV) via topical ocular administration. The NPs were prepared through conjugation of internalizing arginine-glycine-aspartic acid RGD (iRGD; Ac-CCRGDKGPDC) and transactivated transcription (TAT) (RKKRRQRRRC) peptide to polymerized ethylene glycol and lactic-co-glycolic acid. The iRGD sequence can specifically bind with integrin αvβ3, while TAT facilitates penetration through the ocular barrier. 1H nuclear magnetic resonance and high-performance liquid chromatography demonstrated that up to 80% of iRGD and TAT were conjugated to poly(ethylene glycol)– poly(lactic-co-glycolic acid). The resulting particle size was 67.0±1.7 nm, and the zeta potential of the particles was −6.63±0.43 mV. The corneal permeation of iRGD and TAT NPs increased by 5.50- and 4.56-fold compared to that of bare and iRGD-modified NPs, respectively. Cellular uptake showed that the red fluorescence intensity of iRGD and TAT NPs was highest among primary NPs and iRGD- or TAT-modified NPs. CNV was fully formed 14 days after photocoagulation in Brown Norway (BN) rats as shown by optical coherence tomography and fundus fluorescein angiography analyses. Choroidal flat mounts in BN rats showed that the red fluorescence intensity of NPs followed the order of iRGD and TAT NPs > TAT-modified NPs > iRGD-modified NPs > primary NPs. iRGD and TAT dual-modified NPs thus displayed significant targeting and penetration ability both in vitro and in vivo, indicating that it is a promising drug delivery system for managing CNV via topical ocular administration. Keywords: nanoparticles, ocular drug delivery, choroidal neovascularization, RGD, cell-penetrating peptides. Method for iRGD Conjugation: Briefly, Mal–PEG–PLGA was dissolved in acetone and the organic solvent then evaporated, dispersing the solute evenly on the flask wall. The flask was replenished with 0.01 M phosphate-buffered saline (PBS, pH 7.4) and left overnight to react with iRGD. The iRGD was conjugated to Mal–PEG–PLGA (at 4°C, at a 1:1 molar ratio of peptide to Mal–PEG–PLGA).”

End-of-Grant promo, Gamma sterilization, and Carbonate buffer technical notes

The PolySciTech division of Akina, Inc. ( provides a wide array of biodegradable polymers and other research supplies. March ends the fiscal quarter for several institutions and grants which is why we are having a special end-of-quarter promotion. Orders between $100-250 receive a free drink-coozy, orders $250-500 receive a free string-backpack and orders >$500 receive a free PolySciTech T-shirt. As manager of Akina, I receive technical questions and sometimes I receive the same ones quite often. Often, I receive questions about gamma sterilizing our products. Our experience has been, however, that it is common for ionizing radiation techniques such as this to cause some degradation and cross-linking of polyesters which can change their mechanical properties (tend to become brittle) and their solubility properties (may become insoluble). This is similar to literature reports for the effects of radiation on polymers (, One way to reduce this damage is to perform the radiation dosing in an inert gas (argon or nitrogen). We’ve found this reduces some of the reactions which require the participation of atmospheric oxygen, humidity, or other gasses. Alternatively, depending on your application, it may be worthwhile to investigate alternate sterilization techniques such as ethylene oxide exposure. Another issue which has recently come up is the dissolution of thermogelling polymers (PLGA-PEG-PLGA, PLCL-PEG-PLCL) in specific buffers. Thermogel polymers of this category represent a balance between the hydrophilic attractions of the PEG block to water molecules and the hydrophobic attractions of the polyester blocks to each other. Species dissolved in the water which interfere with the water attractions can affect the performance of these thermogels. Although these work well in water, phosphate and several other buffers, they do not work well in carbonate buffers. Likely, this is due to the effects of carbonate species on water’s hydrogen bonding properties ( Poor solubility of these thermogels has been reported in carbonate buffers and avoidance of carbonate buffer is suggested for these materials.