Rapid Detection of SARS-CoV-2 Antigens and Antibodies Using OFET Biosensors Based on a Soft and Stretchable Semiconducting Polymer.

In the midst of the COVID-19 pandemic, adaptive solutions are needed to allow us to make fast decisions and take effective sanitation measures, e.g., the fast screening of large groups (employees, passengers, pupils, etc.). Although being reliable, most of the existing SARS-CoV-2 detection methods cannot be integrated into garments to be used on demand. Here, we report an organic field-effect transistor (OFET)-based biosensing device detecting of both SARS-CoV-2 antigens and anti-SARS-CoV-2 antibodies in less than 20 min. The biosensor was produced by functionalizing an intrinsically stretchable and semiconducting triblock copolymer (TBC) film either with the anti-S1 protein antibodies (S1 Abs) or receptor-binding domain (RBD) of the S1 protein, targeting CoV-2-specific RBDs and anti-S1 Abs, respectively. The obtained sensing platform is easy to realize due to the straightforward fabrication of the TBC film and the utilization of the reliable physical adsorption technique for the molecular immobilization. The device demonstrates a high sensitivity of about 19%/dec and a limit of detection (LOD) of 0.36 fg/mL for anti-SARS-Cov-2 antibodies and, at the same time, a sensitivity of 32%/dec and a LOD of 76.61 pg/mL for the virus antigen detection. The TBC used as active layer is soft, has a low modulus of 24 MPa, and can be stretched up to 90% with no crack formation of the film. The TBC is compatible with roll-to-roll printing, potentially enabling the fabrication of low-cost wearable or on-skin diagnostic platforms aiming at point-of-care concepts.

Sustainable production of dimethyl-protected cyclic lysine over Pd/m-Al2O3-Si catalysts and its application in synthesis of antibacterial nylon‑6 copolymers

• Pd/ m- Al 2 O 3 -Si catalyst exhibited high efficiency in converting α- amino -ε- caprolactam (α- ACL) to dimethyl-protected cyclic lysine (DMCL). • The lack of Brönsted acid sites on Pd/ m- Al 2 O 3 -Si surface facilitated the formation of DMCL and suppressed undesirable reaction process. • Pd/ m- Al 2 O 3 -Si catalyst with microspherical morphology performed excellent stability and physical strength during the catalytic process. • The nylon‑6 copolymers produced from the as-synthesized DMCL exhibited a great potential in the synthesis of self-cleaning antibacterial materials. Antibacterial monomers are prerequisites for synthesizing antibacterial polymers, especially during the current COVID-19 pandemic. Dimethyl-protected cyclic lysine (DMCL) is a promising functional monomer for nylon-6 based self-cleaning antibacterial polymers. However, the production of DMCL still faces formidable challenges, such as harsh reaction conditions and low catalyst activities. In this study, we developed a Pd/ m -Al 2 O 3 -Si catalyst, which exhibited high efficiency in converting α -amino- ε -caprolactam (α -ACL) to DMCL, affording a yield of as high as 97.1% at 100 °C and 1 MPa H 2. The lack of Brönsted acid sites on the catalyst surface facilitated the formation of DMCL and suppressed undesirable hydrolysis or cracking by-products from the lactam-based reactant. The recycled experiments showed that Pd/ m -Al 2 O 3 -Si performed excellent stability and physical strength with essentially no damage to its microspheres after the reaction. The nylon‑6 copolymers produced from the as-synthesized DMCL exhibited similar structure and thermal stability with pure nylon-6, showing great potential in synthesizing the self-cleaning antibacterial polymers. This work provides a sustainable and efficient method for producing DMCL and other lysine-based antibacterial monomers, showing a great prospect for the utilization of bio-based chemicals in synthesizing functional polymers. [ FROM AUTHOR] Copyright of Chemical Engineering Journal is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Multiepitope Subunit Peptide-Based Nanovaccine against Porcine Circovirus Type 2 (PCV2) Elicited High Antibody Titers in Vaccinated Mice.

Porcine circovirus 2 (PCV2) infection is one of the most serious threats to the swine industry. While the disease can be prevented, to some extent, by commercial PCV2a vaccines, the evolving nature of PCV2 necessitates the development of a novel vaccine that can compete with the mutations of the virus. Thus, we have developed novel multiepitope vaccines based on the PCV2b variant. Three PCV2b capsid protein epitopes, together with a universal T helper epitope, were synthesized and formulated with five delivery systems/adjuvants: complete Freund's adjuvant, poly(methyl acrylate) (PMA), poly(hydrophobic amino acid), liposomes and rod-shaped polymeric nanoparticles built from polystyrene-poly(N-isopropylacrylamide)-poly(N-dimethylacrylamide). Mice were subcutaneously immunized with the vaccine candidates three times at three-week intervals. All vaccinated mice produced high antibody titters after three immunizations as analyzed by the enzyme-linked immunosorbent assay (ELISA), while mice vaccinated with PMA-adjuvanted vaccine elicited high antibody titers even after a single immunization. Thus, the multiepitope PCV2 vaccine candidates designed and examined here show strong potential for further development.

Virus removal from aqueous environments with polyelectrolyte coatings on a polypropylene fleece

The adsorption of viruses from aqueous solution is frequently performed to detect viruses. Charged filtration materials capture viruses via electrostatic interactions, but lack the specificity of biological virus‐binding substances like heparin. Herein, we present three methods to immobilize heparin‐mimicking, virus‐binding polymers to a filter material. Two mussel‐inspired approaches are used, based on dopamine or mussel‐inspired dendritic polyglycerol, and post‐functionalized with a block‐copolymer consisting of linear polyglycerol sulfate and amino groups as anchor (lPGS‐b‐NH2). As third method, a polymer coating based on lPGS with benzophenone anchor groups is tested (lPGS‐b‐BPh). All three methods yield dense and stable coatings. A positively charged dye serves as a tool to quantitatively analyze the sulfate content on coated fleece. Especially lPGS‐b‐BPh is shown to be a dense polymer brush coating with about 0.1 polymer chains per nm2. Proteins adsorb to the lPGS coated materials depending on their charge, as shown for lysozyme and human serum albumin. Finally, herpes simplex virus type 1 (HSV‐1) and severe acute respiratory syndrome coronavirus type 2 (SARS‐CoV‐2) can be removed from solution upon incubation with coated fleece materials by about 90% and 45%, respectively. In summary, the presented techniques may be a useful tool to collect viruses from aqueous environments.

Virus removal from aqueous environments with polyelectrolyte coatings on a polypropylene fleece

The adsorption of viruses from aqueous solution is frequently performed to detect viruses. Charged filtration materials capture viruses via electrostatic interactions, but lack the specificity of biological virus-binding substances like heparin. Herein, we present three methods to immobilize heparin-mimicking, virus-binding polymers to a filter material. Two mussel-inspired approaches are used, based on dopamine or mussel-inspired dendritic polyglycerol, and post-functionalized with a block-copolymer consisting of linear polyglycerol sulfate and amino groups as anchor (lPGS-b-NH2). As third method, a polymer coating based on lPGS with benzophenone anchor groups is tested (lPGS-b-BPh). All three methods yield dense and stable coatings. A positively charged dye serves as a tool to quantitatively analyze the sulfate content on coated fleece. Especially lPGS-b-BPh is shown to be a dense polymer brush coating with about 0.1 polymer chains per nm2. Proteins adsorb to the lPGS coated materials depending on their charge, as shown for lysozyme and human serum albumin. Finally, herpes simplex virus type 1 (HSV-1) and severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) can be removed from solution upon incubation with coated fleece materials by about 90% and 45%, respectively. In summary, the presented techniques may be a useful tool to collect viruses from aqueous environments. © 2022 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals LLC.

Microfluidic preparation of antimicrobial microparticles composed of l-lactide/1,3-dioxolane (co)polymers loaded with quercetin.

The resistance of microorganisms against commonly used antibiotics is becoming an increasingly important problem in the food and pharmaceutical industries. Therefore, the development of novel bactericidal agents, as well as the design of drug delivery systems based on materials composed of biocompatible and biodegradable building blocks, has attracted increasing attention. To address this challenge, microparticles composed of l-lactide homopolymer and l-lactide/1,3-dioxolane (co)polymers loaded with quercetin (Q) were fabricated by using a microfluidic technique. This method enables the preparation of homogeneous particles with sizes ranging from 60 to 80 µm, composed of degradable semicrystalline or amorphous (co)polyesters. The microencapsulation of Q in a (co)polymeric matrix enables prolonged release of the antimicrobial agent. The antibacterial properties of the obtained biocompatible microparticles are confirmed by the agar diffusion plate method for various bacterial strains. Therefore, Q-loaded microparticles can have important applications in food preservation as a novel antimicrobial system.

PLA-PEG Diblock Copolymer Micelle as Nanocarrier for Anti-Obesity Drug Delivery System

Obesity is a metabolic condition that accounts for life-threatening disorders like cancer, cardiovascular diseases, and type-2 diabetes. There are several anti-obesity drugs currently available on the market, but many of them show poor bioavailability due to low water solubility. Several attempts have been made by researchers to improve the solubility of orally administered drugs, but many of them did not work properly. Herein, we introduced a block copolymer micelle consisting of poly (lactic acid)-co-poly (ethylene glycol) to improve the solubility of the anti-obesity drug "Fenofibrate”. The block copolymer was synthesized using the polycondensation method, while the micelle was formed when water was added dropwise to the copolymer. Finally, laser light scattering and DLS analysis were used to confirm the micelle formation. The size of the micelle increased from 158 nm to 249 nm after the fenofibrate drug loading inside the hydrophobic core. The polymer PLA-co-PEG can be used as a carrier for orally administered fenofibrate drugs in the future for better water solubility and efficiency. © The Electrochemical Society

Reassessing Undergraduate Polymer Chemistry LaboratoryExperiments for Virtual Learning Environments br

Chemistry laboratory experiments are invaluable tostudents'acquisition of necessary synthetic, analytical, andinstrumental skills during their undergraduate studies. However,the COVID-19 pandemic rendered face-to-face (f2f), in-personteaching laboratory experiences impossible from late 2019-2020and forced educators to rapidly develop new solutions to deliverchemistry laboratory education remotely. Unfortunately, achievinglearning and teaching objectives to the same caliber of in-personexperiments is very difficult through distance learning. Toovercome these hurdles, educators have generated many virtual and remote learning options for not only foundational chemistrycourses but also laboratory experiments. Although the pandemic challenged high-level chemistry education, it has also created anopportunity for both students and educators to be more cognizant of virtual learning opportunities and their potential benefits withinchemistry curriculum. Irrespective of COVID-19, virtual learning techniques, especially virtual lab experiments, can complement f2flaboratories and offer a cost-efficient, safe, and environmentally sustainable alternative to their in-person counterparts.Implementation of virtual and distance learning techniques???including kitchen chemistry and at-home laboratories, prerecordedvideos, live-stream video conferencing, digital lab environment, virtual and augmented reality, and others???can provide a wide-ranging venue to teach chemistry laboratories effectively and encourage diversity and inclusivity in thefield. Despite their relevanceto real-world applications and potential to expand upon fundamental chemical principles, polymer lab experiments areunderrepresented in the virtual platform. Polymer chemistry education can help prepare students for industrial and academicpositions. The impacts of polymers in our daily life can also promote students'interests in science and scientific research. Hence, thetranslation of polymer lab experiments into virtual settings improves the accessibility of polymer chemistry education. Herein, weassess polymer experiments in the emergence of virtual learning environments and provide suggestions for further incorporation ofeffective polymer teaching and learning techniques into virtual settings

Random Copolymers of Lysine and Isoleucine for Efficient mRNA Delivery.

Messenger RNA (mRNA) is currently of great interest as a new category of therapeutic agent, which could be used for prevention or treatment of various diseases. For this mRNA requires effective delivery systems that will protect it from degradation, as well as allow cellular uptake and mRNA release. Random poly(lysine-co-isoleucine) polypeptides were synthesized and investigated as possible carriers for mRNA delivery. The polypeptides obtained under lysine:isoleucine monomer ratio equal to 80/20 were shown to give polyplexes with smaller size, positive ζ-potential and more than 90% encapsulation efficacy. The phase inversion method was proposed as best way for encapsulation of mRNA into polyplexes, which are based on obtained amphiphilic copolymers. These copolymers showed efficacy in protection of bound mRNA towards ribonuclease and lower toxicity as compared to lysine homopolymer. The poly(lysine-co-isoleucine) polypeptides showed greater than poly(ethyleneimine) efficacy as vectors for transfection of cells with green fluorescent protein and firefly luciferase encoding mRNAs. This allows us to consider obtained copolymers as promising candidates for mRNA delivery applications.

Modified Release of the Pineal Hormone Melatonin from Matrix Tablets Containing Poly(L-lactic Acid) and Its PLA-co-PEAd and PLA-co-PBAd Copolymers.

In terms of drug delivery, the attractive properties of poly(L-lactic acid) (PLA) and its aliphatic polyesters, poly(ethylene adipate) (PEAd) and poly(butylene adipate) (PBAd), render them ideal co-formulants for the preparation of modified-release pharmaceutical formulations. Furthermore, we have previously demonstrated that by adding a "softer" aliphatic polyester onto the macromolecular chain of PLA, i.e., PEAd or PBAd, resulting in the formation of the PLA's copolymers (PLA-co-PEAd and PLA-co-PBAd, in 95/5, 90/10, 75/25 and 50/50 weight ratios), the hydrolysis rate is also severely affected, leading to improved dissolution rates of the active pharmaceutical ingredients (API). In the present report, we communicate our findings on the in vitro modified release of the chronobiotic hormone melatonin (MLT), in aqueous media (pH 1.2 and 6.8), from poly(L-lactic acid) and the aforementioned copolymer matrix tablets, enriched with commonly used biopolymers, such as hydroxypropylmethylcellulose (HPMC K15), lactose monohydrate, and sodium alginate. It was found that, depending on the composition and the relevant content of these excipients in the matrix tablets, the release of MLT satisfied the sought targets for fast sleep onset and sleep maintenance. These findings constitute a useful background for pursuing relevant in vivo studies on melatonin in the future.

Synthesis, Properties, and Enzymatic Hydrolysis of Poly(lactic acid)-co-Poly(propylene adipate) Block Copolymers Prepared by Reactive Extrusion.

Poly(lactic acid) (PLA) is a biobased polyester with ever-growing applications in the fields of packaging and medicine. Despite its popularity, it suffers from inherent brittleness, a very slow degradation rate and a high production cost. To tune the properties of PLA, block copolymers with poly(propylene adipate) (PPAd) prepolymer were prepared by polymerizing L-lactide and PPAd oligomers via reactive extrusion (REX) in a torque rheometer. The effect of reaction temperature and composition on the molecular weight, chemical structure, and physicochemical properties of the copolymers was studied. The introduction of PPAd successfully increased the elongation and the biodegradation rate of PLA. REX is an efficient and economical alternative method for the fast and continuous synthesis of PLA-based copolymers with tunable properties.