Monday, September 26, 2016

PLGA from PolySciTech used as part of intranasal vaccine delivery system against group A streptococcus research

PolySciTech division of Akina, Inc (www.polyscitech.com) provides a wide array of biodegradable copolymers for research applications. Group A streptococcus is one cause of lethal rheumatic heart disease as well as other diseases. Intranasal delivery of LCP-1 vaccine is optimal for eliciting an effective immune response. Recently, researchers from The University of Queensland in Australia utilized PLGA from PolySciTech (PolyVivo cat# AP041) to generate vaccine loaded nanoparticles for nasal delivery. This research holds promise for improved vaccine effectiveness. Read more here: Marasini, Nirmal, Zeinab G. Khalil, Ashwini Kumar Giddam, Khairunnisa Abdul Ghaffar, Waleed M. Hussein, Robert J. Capon, Michael R. Batzloff, Michael F. Good, Mariusz Skwarczynski, and Istvan Toth. "Lipid core peptide/poly (lactic-co-glycolic acid) as a highly potent intranasal vaccine delivery system against Group A streptococcus." International Journal of Pharmaceutics (2016). http://www.sciencedirect.com/science/article/pii/S0378517316308870


“Abstract: Rheumatic heart disease represents a leading cause of mortality caused by Group A Streptococcus (GAS) infections transmitted through the respiratory route. Although GAS infections can be treated with antibiotics these are often inadequate. An efficacious GAS vaccine holds more promise, with intranasal vaccination especially attractive, as it mimics the natural route of infections and should be able to induce mucosal IgA and systemic IgG immunity. Nanoparticles were prepared by either encapsulating or coating lipopeptide-based vaccine candidate (LCP-1) on the surface of poly(lactic-co-glycolic acid) (PLGA). In vitro study showed that encapsulation of LCP-1 vaccine into nanoparticles improved uptake and maturations of antigen-presenting cells. The immunogenicity of lipopeptide incorporated PLGA-based nanoparticles was compared with peptides co-administered with mucosal adjuvant cholera toxin B in mice upon intranasal administration. Higher levels of J14-specific salivary mucosal IgA and systemic antibody IgG titres were observed for groups immunized with encapsulated LCP-1 compared to LCP-1 coated nanoparticles or free LCP-1. Systemic antibodies obtained from LCP-1 encapsulated PLGA NPs inhibited the growth of bacteria in six different GAS strains. Our results show that PLGA-based lipopeptide delivery is a promising approach for rational design of a simple, effective and patient friendly intranasal GAS vaccine resulting in mucosal IgA response. Keywords: Nanoparticles; Lipopeptides; PLGA; Vaccine; Mucosal immunology”


Friday, September 23, 2016

mPEG-PCL used for targeted dexamethasone delivery to inflamed joints as part of arthritis treatment research.

PolySciTech division of Akina, Inc. (www.polyscitech.com) provides a wide array of biodegradable block copolymers including mPEG-PCL. Arthritis is a highly prevalent immune disorder which leads to joint destruction. It can be treated with anti-inflammatory agents, such as dexamethasone (a steroidal anti-inflammatory), but systemic application of this drug can lead to side-effects. Injecting the drug locally into joints is problematic as more than one joint may be affected by arthritis. Recently, mPEG-PCL was utilized to generate dexamethasone micelles and injected into an arthritic rat model intravenously. As part of inflammatory process, the vasculature around inflamed tissue becomes very ‘leaky’ and allows for easy passage of nanoparticles into inflamed tissue. This process allowed for preferential uptake of the mPEG-PCL nanoparticles into the inflamed arthritic tissue where the dexamethasone served to reduce inflammation and tissue damage. This targeted delivery allows for treatment of multiple joints from one injection and prevents side effects. This research holds promise for improved arthritis treatment. Read more: Wang, Qin, Jiayu Jiang, Wenfei Chen, Hao Jiang, Zhirong Zhang, and Xun Sun. "Targeted delivery of low-dose dexamethasone using PCL–PEG micelles for effective treatment of rheumatoid arthritis." Journal of Controlled Release 230 (2016): 64-72. http://www.sciencedirect.com/science/article/pii/S0168365916301821.


“Abstract: Glucocorticoid (GC) is the cornerstone therapy of rheumatoid arthritis, but high doses are associated with serious adverse effects. In an effort to improve the efficacy of low-dose GC therapy, we developed a micelle system for targeted delivery to inflamed joints and validated the approach in a rat model of arthritis. Micelles loaded with dexamethasone (Dex) self-assembled from the amphipathic poly (ethylene glycol)-block–poly (ε­caprolactone) (PCL–PEG) polymer via film dispersion, and they were injected intravenously at a dose of only 0.8 mg/kg into rats with adjuvant-induced arthritis. The micelles persisted for a relatively long time in the circulation, and they accumulated preferentially in inflamed joints. Micelle-delivered Dex potently reduced joint swelling, bone erosion, and inflammatory cytokine expression in both joint tissue and serum. PCL–PEG micelles caused only moderate adverse effects on body weight, lymphocyte count and blood glucose concentration, and they weakly activated the host complement system. These results suggest that encapsulating Dex in PCL–PEG micelles may allow for safe and effective low-dose GC therapy targeting inflammatory disorders. Keywords: rheumatoid arthritis; PCL–PEG; Dexamethasone; Side effect”


Tuesday, September 20, 2016

Thermogel applications of PolySciTech products

PolySciTech division of Akina, Inc. (www.polyscitech.com) provides a wide variety of biodegradable polymers some of which exhibit reverse thermal gelation. This process occurs for polymers that have a mixture of hydrophilic and hydrophobic regions. In cold conditions, the water molecules preferentially affiliate with the hydrophilic portions of the polymer and the material dissolves into micelles. At higher temperatures, the water molecules transition to a free state and the polymer micelles form bridges between each other to form a gel held together by weak hydrophobic interactions (e.g. London dispersion forces).  There are many practical applications for these materials. Here’s a few, recently published applications of note:

Prostate cancer treatment/vaccine adjuvant: Auburn University researchers utilized PolyVivo AK097 (PLGA-PEG-PLGA) as a delivery agent for vaccines against the sex hormone GnRH. Such a system holds promise for both fertility control as well as prostate cancer treatment. (http://www.sciencedirect.com/science/article/pii/S0168165615301498)

Gel-Printing: Collaborators at Purdue University and KITECH utilized PolyVivo AO023 (PNIPAM-co-AM) as a gel printing system in which an inkjet-printer was modified so as to print the cold polymer solution onto a warmed surface. This system holds promise for controlled printing of living cells or tissues. (http://www.sciencedirect.com/science/article/pii/S0017931015310565)

Wound disinfection: Researchers at the University of Toronto utilized PolyVivo AO031 (PNVCL) as a carrier of gold nanorods into an infected wound model. By applying a carefully defined laser to the system, they were able to rapidly raise the temperature of the wound surface without increasing temperature underneath allowing for extremely precise, localized heating. This system kills bacteria regardless of antibiotic resistance. This system holds promise for treatment of MRSA or other localized infections where conventional antibiotics are ineffective. (http://www.sciencedirect.com/science/article/pii/S0142961216301144)

These are just a few examples. For all PST research products, you can see research articles and other literature regarding their usage at our site here https://akinainc.com/polyscitech/products/polyvivo/referenced_by.php

Tuesday, September 13, 2016

PolySciTech Poly(caprolactone) used as part of development of a theranostic nanoparticle system as a potential treatment for cancer

PolySciTech division of Akina, Inc. (www.polyscitech.com) provides a wide array of biodegradable polymers. Recently, PCL from PolySciTech (PolyVivo catalog AP113) was used as part of development of an NIR sensitive nanoparticle system for delivery of paclitaxel. This research holds promise for improved therapeutic strategies. Read more: Su, Jinghan, Huiping Sun, Qingshuo Meng, Qi Yin, Pengcheng Zhang, Zhiwen Zhang, Haijun Yu, and Yaping Li. "Bioinspired Nanoparticles with NIRControlled Drug Release for Synergetic Chemophotothermal Therapy of Metastatic Breast Cancer." Advanced Functional Materials (2016). http://onlinelibrary.wiley.com/doi/10.1002/adfm.201603381/full


 “Abstract: Optimal nanosized drug delivery systems (NDDS) require long blood circulation and controlled drug release at target lesions for efficient anticancer therapy. Red blood cell (RBC) membrane-camouflaged nanoparticles (NPs) can integrate flexibility of synergetic materials and highly functionality of RBC membrane, endowed with many unique advantages for drug delivery. Here, new near-infrared (NIR)-responsive RBC membrane-mimetic NPs with NIR-activated cellular uptake and controlled drug release for treating metastatic breast cancer are reported. An NIR dye is inserted in RBC membrane shells, and the thermoresponsive lipid is employed to the paclitaxel (PTX)-loaded polymeric cores to fabricate the RBC-inspired NPs. The fluorescence of dye in the NPs can be used for in vivo tumor imaging with an elongated circulating halftime that is 12.3-folder higher than that of the free dye. Under the NIR laser stimuli, the tumor cellular uptake of NPs is significantly enhanced to 2.1-fold higher than that without irradiation. The structure of the RBC-mimetic NPs can be destroyed by the light-induced hyperthermia, triggered rapid PTX release (45% in 30 min). These RBC-mimetic NPs provide a synergetic chemophotothermal therapy, completely inhibited the growth of the primary tumor, and suppress over 98% of lung metastasis in vivo, suggesting it to be an ideal NDDS to fight against metastatic breast cancer.”

PolySciTech PLGA used as part of research investigating drug-eluting electrospun mesh systems

PolySciTech Division of Akina, Inc. (www.polyscitech.com) provides a wide array of biodegradable polymers. Recently, researchers at University of Washington used PolySciTech PLGA (PolyVivo Cat# AP154) as part of an electrospun system for delivery of model drug tenofovir (a hydrophilic antiretroviral medication). They investigated this system both in terms of drug release as well as the relationship between drug release and polymer degradation and mechanical performance. This research holds promise for improved drug-eluting polymer meshes which could be used for a wide array of applications. Read more: Chou, Shih-Feng, and Kim A. Woodrow. "Relationships between mechanical properties and drug release from electrospun fibers of PCL and PLGA blends." Journal of the Mechanical Behavior of Biomedical Materials (2016). http://www.sciencedirect.com/science/article/pii/S1751616116303101

“Highlights Drug-polymer interactions in electrospun drug-eluting fibers. Correlations of drug release, polymer degradation on fiber tensile properties. Drug partitioning in blend polyester fibers. Abstract: Electrospun nanofibers have the potential to achieve high drug loading and the ability to sustain drug release. Mechanical properties of the drug-incorporated fibers suggest the importance of drug-polymer interactions. In this study, we investigated the mechanical properties of electrospun polycaprolactone (PCL) and poly (D,L-lactic-co-glycolic) acid (PLGA) fibers at various blend ratios in the presence and absence of a small molecule hydrophilic drug, tenofovir (TFV). Young's modulus of the blend fibers showed dependence of PLGA content and the addition of the drug. At PCL/PLGA (20/80) composition, Young's modulus and tensile strength were independent of drug loading up to 40 wt% due to offsetting effect from drug-polymer interactions. In vitro drug release studies suggested that release of TFV significantly decreased fiber mechanical properties. In addition, mechanically stretched fibers displayed a faster release rate as compared to the non-stretched fibers. Finally, drug partition in the blend fibers was estimated using a mechanical model and then experimentally confirmed by using a composite of individually stacked fiber meshes. This work provides scientific understanding on the dependence of drug release and drug loading on the mechanical properties of drug-eluting fibers. Keywords: Electrospun fibers; Mechanical properties; Drug loading; Drug release; Drug-polymer interaction; Drug partition”

Friday, September 2, 2016

PLGA-NH2 from PolySciTech investigated for improved cellular uptake as chemotherapy delivery system

PolySciTech Division of Akina, Inc. (www.polyscitech.com) provides a wide array of biodegradable copolymers including Amine endcapped PLGA. Recently, researchers at Kangwon National University in Korea utilized PLGA-NH2 (PolyVivo AI062) and unreactive PLGA (PolyVivo AP063) from PolySciTech to develop a nanoparticle system for the delivery of phloretin (a natural dihydrochalcone which induces cancer apoptosis, doi: 10.1002/ijc.24189) to test Hep-2 cells (human laryngeal carcinoma). This research holds promise for improved chemotherapeutic strategies. Read more: Lee, Song Yi, and Hyun-Jong Cho. "Amine-functionalized poly (lactic-co-glycolic acid) nanoparticles for improved cellular uptake and tumor penetration." Colloids and Surfaces B: Biointerfaces (2016). http://www.sciencedirect.com/science/article/pii/S0927776516306270

“Abstract: Amine-functionalized poly(lactic-co-glycolic acid) (PLGA-NH2) nanoparticles (NPs) were developed for the delivery of phloretin. PLGA-NH2/phloretin NPs with 237 nm mean diameter, narrow size distribution, and around −6 mV zeta potential were fabricated by a modified emulsification-solvent evaporation method. The results of solid state studies revealed that drug was successfully incorporated into the polymeric NPs. The initial particle size of developed NPs was maintained after 24 h incubation in human serum albumin (HSA) solution, fetal bovine serum (FBS), and phosphate buffered saline (PBS). Sustained and higher drug release patterns at acidic pH (pH 5.5), compared with neutral pH (pH 7.4), from PLGA-NH2 NPs were observed. The experimental data of flow cytometry and confocal laser scanning microscopy (CLSM) studies suggested that PLGA-NH2 NPs may have an improved cellular accumulation efficiency, compared with PLGA NPs, in Hep-2 cells (human laryngeal carcinoma). Also, PLGA-NH2 NPs exhibited enhanced growth inhibitory effects rather than PLGA NPs in Hep-2 spheroid model. By introducing a simple strategy based on amine-functionalization of PLGA NPs (without installing complicated functional moieties), improved cellular uptake and antitumor efficacies without severe toxicity, compared with unmodified PLGA NPs, have been accomplished. Highlights: Poly(lactic-co-glycolic acid)-amine (PLGA-NH2) nanoparticles (NPs) were fabricated. Phloretin was encapsulated into the PLGA-NH2 NPs for tumor-targeted delivery. PLGA-NH2 NPs exhibited an improved cellular accumulation, compared with PLGA NPs. Enhanced tumor penetration efficiency in spheroids was observed in PLGA-NH2 NPs group.”


Tuesday, August 30, 2016

Have Some Fun With PolySciTech Invaders:

PolySciTech division of Akina, Inc (www.polyscitech.com) provides a wide array of biodegradable block copolymers and other research products. Despite the seriousness of our work, we do have a sense of fun. As a fun way to say ‘Thank You’ to our customers, we’ve uploaded a playable PolySciTech Invaders game, which has prizes including product discount codes and t-shirts onto our website. Check out the game here http://polyscitech.com/invaders/.