Wednesday, September 18, 2019

PLGA from PolySciTech used in development of small-scale melt-processing system.



Melt processing is the process by which a polymer is heated to a fluid state and then forced into a mold or through a cavity to adapt into a specific shape. This includes many common techniques for generating products from polymers or plastic such as blow-molding, extrusion, injection molding, and vacuum forming. The vast majority of melt-processing equipment is designed to process kilo’s to metric tons of polymers and are designated for manufacturing. This creates a condition which is prohibitive to researchers looking to perform melt-processing on polymers at small scale for testing and development. Recently, researchers at University of California used PLGA (AP041) from PolySciTech (www.polyscitech.com) in their development of a small-scale melt-processing system. This research holds promise to enable research and development of materials made by this processing method. Read more: Wirth, David M., and Jonathan K. Pokorski. "Design and fabrication of a low-cost pilot-scale melt-processing system." Polymer (2019): 121802. https://www.sciencedirect.com/science/article/pii/S0032386119308080

“Highlights: Schematics for facile assembly of a lab scale mini-injection molding system. Less than $500 in raw materials, melt processes polymers at up to 250 °C with 100 MPa pressure. Ideal for small samples 50–500 mg total mass with low dead volume. Non-newtonian modeling of shear rate inside melt processing system. Abstract: Melt processing of polymeric materials is a ubiquitous technique for forming, shaping, refining and homogenizing polymers and polymer composites. Melt-processing techniques are the primary manufacturing method of consumer and industrial thermoplastic parts, especially when using commodity polymers with high-throughput production. Melt-processing, however, is underutilized in academic laboratories when developing high value-added materials due to the capital expense of the equipment and relatively large-scale required to carry out such processing. These concerns make pilot-scale melt-processing challenging, particularly for the development of new polymers or polymer composites where materials can only be generated in small-scale at reasonable costs. The current study designs and evaluates a bench-top, sub-milliliter volume extrusion and injection-molding device, which sources parts from current 3D printer technology at minimal expense. The plans presented will open this convenient technique to academic research laboratories interested in pilot-scale experiments. A systematic approach to melt processing of PLA, PLGA, and PCL polymer composites is demonstrated. Characterization of the dispersion of pharmaceuticals, small molecules and nanoparticles in melt processed polymers is presented as a demonstration of potential utility. Keywords: Melt processing Composites Injection molding Polymer engineering”

Wednesday, September 4, 2019

PLGA from PolySciTech used in development of iron-chelator nanodelivery system as a treatment for cancer


An ideal chemotherapeutic would be a compound which is highly toxic towards cancerous cells but relatively benign towards normal (healthy) cells. Most conventional chemotherapeutics (such as paclitaxel, 5FU, docetaxel, etc.) are not so selective and rather present a generic propensity to prevent growth of both cancerous and healthy cells leading to severe side-effects. Research has identified compounds which present limited toxicity against normal cells while maintaining high efficacy against cancer cells. Recently, researchers at University of Houston and The Pennsylvania State University used PLGA (AP023 and AP165) from PolySciTech (www.polyscitech.com) to create nanoparticles for delivery of a novel anticancer chelator compound Dp44mT. This research holds promise to provide a novel means of treating cancer with limited side effects. Read more: Claire K. Holley, You Jung Kang, Chung-Fan Kuo, Mohammad Reza Abidian, Sheereen Majd “Development and In Vitro Assessment of an Anti-Tumor Nano-Formulation” Colloids and Surfaces B: Biointerfaces 2019, 110481 https://www.sciencedirect.com/science/article/pii/S0927776519306253.

“Highlights: Iron chelator Dp44mT was efficiently encapsulated in PLGA NPs of 50-120 nm size. Dp44mT-NPs were highly toxic to glioma cell lines, U251 and U87, with IC50

PLGA-PEG-COOH from PolySciTech used in research on acoustic-microfluidic techniques to generate nanoparticles


There are many different techniques which can be applied to the generation of nanoparticles and the method applied drastically affects the particles properties. Notably, microfluidic techniques enable the generation of extremely reproducible nanoparticles with tight sizing control. Recently, researchers at Duke University used PLGA-PEG-COOH (AI056, AI076, AI078, and AI171) from PolySciTech (www.polyscitech.com) to generate nanoparticles by a novel acoustic-microfluidic mechanism. This research holds promise for the generation of highly controlled nanoparticles for drug-delivery applications. Read more: Huang, Po‐Hsun, Shuaiguo Zhao, Hunter Bachman, Nitesh Nama, Zhishang Li, Chuyi Chen, Shujie Yang, Mengxi Wu, Steven Peiran Zhang, and Tony Jun Huang. "Acoustofluidic Synthesis of Particulate Nanomaterials." Advanced Science (2019): 1900913. (https://onlinelibrary.wiley.com/doi/full/10.1002/advs.201900913)

“Abstract: Synthesis of nanoparticles and particulate nanomaterials with tailored properties is a central step toward many applications ranging from energy conversion and imaging/display to biosensing and nanomedicine. While existing microfluidics‐based synthesis methods offer precise control over the synthesis process, most of them rely on passive, partial mixing of reagents, which limits their applicability and potentially, adversely alter the properties of synthesized products. Here, an acoustofluidic (i.e., the fusion of acoustic and microfluidics) synthesis platform is reported to synthesize nanoparticles and nanomaterials in a controllable, reproducible manner through acoustic‐streaming‐based active mixing of reagents. The acoustofluidic strategy allows for the dynamic control of the reaction conditions simply by adjusting the strength of the acoustic streaming. With this platform, the synthesis of versatile nanoparticles/nanomaterials is demonstrated including the synthesis of polymeric nanoparticles, chitosan nanoparticles, organic–inorganic hybrid nanomaterials, metal–organic framework biocomposites, and lipid‐DNA complexes. The acoustofluidic synthesis platform, when incorporated with varying flow rates, compositions, or concentrations of reagents, will lend itself unprecedented flexibility in establishing various reaction conditions and thus enable the synthesis of versatile nanoparticles and nanomaterials with prescribed properties.”

Friday, August 30, 2019

PLA from PolySciTech used in analysis of mechanical and physical properties for engineering applications

If you have ever carried groceries in a plastic bag, you are familiar with mechanical deformation of polymers. Notably, for LDPE (material used to make bags), pulling on the polymer causes a series of transitions to occur in which the polymer chains pull out in the direction of the force causing the polymer to grow hard and crystalline in the direction of deformation. This is why when you grab the bag handles they first draw out and grow brighter, narrower, and harder as the polymer elongates under the weight of the stuff inside. At some point the chains have been pulled out as far as they will go and the bag handles become very crystalline and strong enough to be very painful for your hands. All of this is due to polymer transitions under mechanical stress. Recently, researchers at University of Wisconsin used PLA (AP164) from PolySciTech (www.polyscitech.com) to create PLA films for testing of physical and mechanical properties of these polymers. This research holds promise to provide for improved use of these polymers as engineering materials. Read more: Bennin, Trevor, Josh Ricci, and M. D. Ediger. "Enhanced Segmental Dynamics of Poly (lactic acid) Glasses during Constant Strain Rate Deformation." Macromolecules (2019). https://pubs.acs.org/doi/abs/10.1021/acs.macromol.9b01363

“The combined effects of temperature and deformation on the segmental dynamics of poly(lactic acid) (PLA) glasses were investigated by using probe reorientation measurements. Constant strain rate deformations, with strain rates between 6 × 10–6 and 3 × 10–5 s–1, were performed on PLA glasses at temperatures between Tg – 15 K and Tg – 25 K. Deformation decreases the segmental relaxation time by up to a factor of 30 relative to the undeformed state. The segmental relaxation time in the postyield regime is related to the local strain rate via a power law, with exponents similar to those reported for lightly cross-linked PMMA. The Kohlrausch–Williams–Watts exponent, βKWW, commonly interpreted in terms of the width of the distribution of segmental relaxation times, changes from the undeformed state to the postyield regime, indicating a significant narrowing of the relaxation spectrum. We observe that βKWW is correlated to the deformation-induced increase of segmental mobility for PLA, as was reported for PMMA. The similar responses of PLA and PMMA to deformation suggest that the observed effects are the generic consequences of constant strain rate deformation on the segmental dynamics of polymer glasses.”

Monday, August 19, 2019

PLGA, PEG-PLGA, PLGA-Folate from PolySciTech used in research on chemotherapeutic nanocarriers


There are a multitude of nanoparticle strategies currently in development for applications towards treatment of cancer. Despite this, there is still a great deal which remains to be discovered in terms of the exact nature of the nanoparticle/biological interactions. Additionally, the optimal formulation approach remains to be determined. Recently, researchers at Wroclaw University (Poland) used PLGA (AP022), mPEG-PLGA (AK037), and PLGA-Folate (AO037) from PolySciTech (www.polyscitech.com) to develop different types of nanoparticles and tested their use for chemotherapy delivery. This research holds promise for improved therapies against cancer in the future. Read more: Bazylińska, Urszula, Julita Kulbacka, and Grzegorz Chodaczek. "Nanoemulsion Structural Design in Co-Encapsulation of Hybrid Multifunctional Agents: Influence of the Smart PLGA Polymers on the Nanosystem-Enhanced Delivery and Electro-Photodynamic Treatment." Pharmaceutics 11, no. 8 (2019): 405. https://www.mdpi.com/1999-4923/11/8/405

“Abstract: In the present study, we examined properties of poly(lactide-co-glycolide) (PLGA)-based nanocarriers (NCs) with various functional or “smart” properties, i.e., coated with PLGA, polyethylene glycolated PLGA (PEG-PLGA), or folic acid-functionalized PLGA (FA-PLGA). NCs were obtained by double emulsion (water-in-oil-in-water) evaporation process, which is one of the most suitable approaches in nanoemulsion structural design. Nanoemulsion surface engineering allowed us to co-encapsulate a hydrophobic porphyrin photosensitizing dye—verteporfin (VP) in combination with low-dose cisplatin (CisPt)—a hydrophilic cytostatic drug. The composition was tested as a multifunctional and synergistic hybrid agent for bioimaging and anticancer treatment assisted by electroporation on human ovarian cancer SKOV-3 and control hamster ovarian fibroblastoid CHO-K1 cell lines. The diameter of PLGA NCs with different coatings was on average 200 nm, as shown by dynamic light scattering, transmission electron microscopy, and atomic force microscopy. We analyzed the effect of the nanocarrier charge and the polymeric shield variation on the colloidal stability using microelectrophoretic and turbidimetric methods. The cellular internalization and anticancer activity following the electro-photodynamic treatment (EP-PDT) were assessed with confocal microscopy and flow cytometry. Our data show that functionalized PLGA NCs are biocompatible and enable efficient delivery of the hybrid cargo to cancer cells, followed by enhanced killing of cells when supported by EP-PDT. Keywords: smart nanocarriers; folic acid; verteporfin; cisplatin; SKOV-3 cells; CHO-K1 cells; electroporation; theranostic cargo; double emulsion approach”

Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference hosted by Akina, Inc. on Aug 28, 2019. See more and register at http://bpcrconference.com

Maleimide-PEG-PLGA from PolySciTech used in development of bladder cancer therapy


One treatment option for bladder cancer is delivery of chemotherapeutics directly into the bladder itself (Intravesical Therapy). Delivery of chemotherapeutics to bladder cancer tumors by this method is difficult due to the low permeability of the bladder, periodic voiding, and other limitations. Recently, researchers at University of Reading (United Kingdom), Al-Farabi Kazakh National University (Kazakhstan), Heinz Maier-Leibnitz Zentrum(Germany) and Harvard University used PLGA-PEG-Mal (AI020, AI109) from PolySciTech (www.polyscitech.com) to develop muco-adhesive nanoparticles. This research holds promise to provide for improved therapeutic strategies against bladder cancer. Read more: Kaldybekov, Daulet B., Sergey K. Filippov, Aurel Radulescu, and Vitaliy V. Khutoryanskiy. "Maleimide-functionalised PLGA-PEG nanoparticles as mucoadhesive carriers for intravesical drug delivery." European Journal of Pharmaceutics and Biopharmaceutics (2019). https://www.sciencedirect.com/science/article/abs/pii/S0939641119307258

“Abstract: Low permeability of the urinary bladder epithelium, poor retention of the chemotherapeutic agents due to dilution and periodic urine voiding as well as intermittent catheterisations are the major limitations of intravesical drug delivery used in the treatment of bladder cancer. In this work, maleimide-functionalised poly(lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-PEG-Mal) nanoparticles were developed. Their physicochemical characteristics, including morphology, architecture and molecular parameters have been investigated by means of dynamic light scattering, transmission electron microscopy and small-angle neutron scattering techniques. It was established that the size of nanoparticles was dependent on the solvent used in their preparation and molecular weight of PEG, for example, 105 ± 1 nm and 68 ± 1 nm particles were formed from PLGA20K-PEG5K in dimethyl sulfoxide and acetone, respectively. PLGA-PEG-Mal nanoparticles were explored as mucoadhesive formulations for drug delivery to the urinary bladder. The retention of fluorescein-loaded nanoparticles on freshly excised lamb bladder mucosa in vitro was evaluated and assessed using a flow-through fluorescence technique and Wash Out50 (WO50) quantitative method. PLGA-PEG-Mal nanoparticles (NPs) exhibited greater retention on urinary bladder mucosa (WO50 = 15 mL) compared to maleimide-free NPs (WO50 = 5 mL). The assessment of the biocompatibility of PEG-Mal using the slug mucosal irritation test revealed that these materials are non-irritant to mucosal surfaces. Graphical abstract: Schematic illustration depicting the mechanism of enhanced mucoadhesion of PLGA-PEG-Mal nanoparticles on urinary bladder mucosa. Keywords: urinary bladder intravesical drug delivery PLGA-PEG maleimide nanoparticles small-angle neutron scattering slug mucosal irritation test muco-adhesion Wash Out50 (WO50)”

Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference hosted by Akina, Inc. on Aug 28, 2019. See more and register at http://bpcrconference.com

BPCR Registration Deadlines Approaching

Registration deadlines for BPCR, a free, 1-day scientific-networking conference hosted by Akina, Inc. on Aug 28, 2019, are approaching. See more and register at bpcrconference.com
PRESENT/EXHIBIT: Registration to present or exhibit closes August 20th at midnight (EST).
ATTEND: Registration to attend closes August 25th at midnight (EST).  
Note that preregistration is not mandatory to attend. It is only required to receive the free lunch.