SARS-CoV-2 poses a major threat to the public health worldwide, as it causes a respiratory disease named COVID-19. Since the first case report in December 2019, a pandemic ensued with approximately one million deaths within the first nine months. [1] SARS-CoV-2 belongs to the beta-coronavirus genus. All coronaviruses have a lipid envelope with a capsid, which encapsulates the helical nucleocapsid with the RNA genome. [2] The most prominent viral envelope component is the spike glycoprotein (S), which interacts with the angiotensin-converting enzyme 2 (ACE2) on the surface of host cells and initiates virus entry, the first step of the SARS-CoV-2 infection cycle. [1,3-5] Moreover, the polybasic cleavage site of S is found to play a crucial role in the binding between the virus and ACE2. [6] Numerous efforts have been devoted to development of vaccines that generate neutralizing antibodies toward S to block viral interaction with Search of new strategies for the inhibition of respiratory viruses is one of the urgent health challenges worldwide, as most of the current therapeutic agents and treatments are inefficient. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic and has taken lives of approximately two million people to date. Even though various vaccines are currently under development, virus, and especially its spike glycoprotein can mutate, which highlights a need for a broad-spectrum inhibitor. In this work, inhibition of SARS-CoV-2 by graphene platforms with precise dual sulfate/alkyl functionalities is investigated. A series of graphene derivatives with different lengths of aliphatic chains is synthesized and is investigated for their ability to inhibit SARS-CoV-2 and feline coronavirus. Graphene derivatives with long alkyl chains (>C9) inhibit coronavirus replication by virtue of disrupting viral envelope. The ability of these graphene platforms to rupture viruses is visualized by atomic force microscopy and cryogenic electron microscopy. A large concentration window (10 to 100-fold) where graphene platforms display strongly antiviral activity against native SARS-CoV-2 without significant toxicity against human cells is found. In this concentration range, the synthesized graphene platforms inhibit the infection of enveloped viruses efficiently, opening new therapeutic and metaphylactic avenues against SARS-CoV-2. The ORCID identification number(s) for the author(s) of this article can be found under

An adaptable approach toward cleavable nanoparticle carrier systems for photodynamic therapy (PDT) is presented, comprising a biocompatible carrier loaded with multiple photosensitizer (PS) molecules related to the clinically employed PS Temoporfin, two linkers cleavable under different triggers and glyco-targeting with mannose. A synthetic pathway to stimuli responsive hyperbranched polyglycerol (hPG) porphyrin conjugates via the copper(I)-catalyzed 1,3-dipolar cycloaddition (CuAAC) or the strain-promoted alkyne-azide cycloaddition (SPAAC) has been developed. The PS 10,15,20-tris(3-hydroxyphenyl)-5-(2,3,4,5,6-pentafluorophenyl)porphyrin was functionalized with disulfide containing cystamine and acid-labile benzacetal linkers. Conjugates with reductively and pH labile linkers were thus obtained. Cleavage of the active PS agents from the polymer carrier is shown in several different release studies. The uptake of the conjugates into the cells is demonstrated via confocal laser scanning microscopy (CLSM) and flow cytometry. Finally, the antitumor and antibacterial phototoxicity of selected conjugates has been assessed in four different tumor cell lines and in cultures of the bacterium Staphylococcus aureus. The conjugates exhibited phototoxicity in several tumor cell lines in which conjugates with reductively cleavable linkers were more efficient compared to conjugates with acid-cleavable linkers. For S. aureus, strong phototoxicity was observed for a combination of the reductively cleavable and the pH labile linker and likewise for the cleavable conjugate with mannose targeting groups. The results thus suggest that the conjugates have potential for antitumor as well as antibacterial PDT.

Targeted delivery and extended blood circulation of anticancer drugs have been the challenges for decreasing the adverse side effects and improving the therapeutic efficiency in cancer chemotherapy. Herein, we present a drug delivery system (DDS) based on biodegradable dendritic polyglycerol sulfatebearing poly(caprolactone) (dPGS-PCL) chains, which has been synthesized on 20 g scale using a straightforward two-step protocol. In vivo fluorescence imaging demonstrated a significant accumulation of the DDS in the tumor environment. Sunitinib, an anticancer drug, was loaded into the DDS and the drug-induced toxicity was investigated in vitro and in vivo. The drug encapsulated in dPGS-PCL and the free drug showed similar toxicities in A431 and HT-29 cells, and the cellular uptake was comparable. The straightforward and large-scale synthesis, the organic solvent-free drug-loading approach, together with the tumor targetability of the biodegradable dendritic polyglycerols, render this copolymer a promising candidate for targeted cancer nanomedicine drug delivery systems.

Alkyl sulfoxide side groups introduce thermo- and oxidation-sensitivity into poly(meth)acrylates, thus realizing new dual-responsive homopolymers based on one functional group.

Herpes Simplex Virus-1 (HSV-1) with a diameter of 155-240 nm uses electrostatic interactions to bind with the heparan sulfate present on the cell surface to initiate infection. In this work, the initial contact using polysulfate-functionalized hydrogels is aimed to deter. The hydrogels provide a large contact surface area for viral interaction and sulfated hydrogels are good mimics for the native heparan sulfate. In this work, hydrogels of different flexibilities are synthesized, determined by rheology. Gels are prepared within an elastic modulus range of 10-1119 Pa with a mesh size of 80-15 nm, respectively. The virus binding studies carried out with the plaque assay show that the most flexible sulfated hydrogel performs the best in binding HSV viruses. These studies prove that polysulfated hydrogels are a viable option as HSV-1 antiviral compounds. Furthermore, such hydrogel networks are also physically similar to naturally occurring mucus gels and therefore may be used as mucus substitutes.