Despite the three-dimensional structure of tissues in vivo, the researches on the structures, functions and pathology of human tissues frequently relies on the two-dimensional (2D) model in vitro and animal model. Since the structure of monolayer in vitro model is quite different from the cell microenvironment in vivo, cell behaviors and functions, such as cell–cell interaction and cell-matrix interaction, are greatly affected. Moreover, animal model often fail to repeat the human characteristic because of species differences. Three-dimensional (3D) culture of tumor cell lines has been advocated as the alternative. It is simple and practicable and has the advantage of simulating the cell microenvironment in vivo. Matrices for 3D cell culture mimic one or more properties of the extracellular matrix (ECM) and tumor microenvironment in vivo. The 3D cell culturing matrices are generally composed of porous structures with diameter less than 300 nm, which can provide enough space for the growth of cells. The cancer cells can form 3D aggregates or spheroids inside the matrix. According to the main component, 3D cell culture matrices can be divided into two main categories: matrix based on natural materials and matrix based on synthetic materials. Matrices based on natural materials can provide a biological environment, but the mechanical performance of materials is commonly poor and the batch-to-batch discrepancy cannot be completely eliminated. Natural materials are usually used to form hydrogel composites. Synthetic scaffolds are polymers like Polyethylene glycol (PEG), Polylactide (PLA), Poly(lactide-co-glycolide) (PLGA/PLG) which are biodegradable and easy to reproduce. Among these materials, the thermogelling synthetic copolymer hydrogels with a sol-gel transition exhibit lower critical solution temperature (LCST) behavior, which is meaningful for a 3D cell culturing matrix. When the sol gel transition temperature of smart hydrogel is between 5℃ and 37℃, the matrix has advantages in further separation of materials and cell aggregates. Hydrogels have received extensive attention in tissue engineering and 3D cell culture, owing to their inherent properties such as flexible matrix, high water content, and responsive network structures. Hydrogels can be formed both chemically and physically. PEG hydrogels are excellent candidates as biomaterials because of their potential for incorporating both biophysical and biochemical cues and their prevention of non-specific protein adsorption, biocompatibility and FDA approval for use in humans. Thermo-sensitive hydrogel based on PLGA-PEG-PLGA tri-block copolymers has been used for delivery of proteins and water-insoluble drugs. The proper LCST and good biocompatibility of PLGA-PEG-PLGA tri-block copolymers make it a good choice for in vitro cell culture matrix. References 1. Caldwell A. S., Aguado B. A., Anseth K. S. Designing Microgels for Cell Culture and Controlled Assembly of Tissue Microenvironments. Adv Fu...

Cancer remains one of the most common diseases that is a threat to human health. Currently, chemotherapy is an important and indispensable strategy for treating cancer besides surgical treatment and radiotherapy. Thus, it has attracted a number of pharmaceutical researchers for the discovery and development of new anticancer drugs. Unfortunately, approximately 90% of drug candidate molecules in the discovery pipeline are poorly water soluble. Poor solubility can elicit low oral bioavailability and insufficient efficacy in vivo, and make intravenous (IV) administration challenging. Nanotechnology-based drug delivery systems, such as drug nanocrystals (NCs) and liposomes have enabled in improving the solubility and/or attained targeted delivery via the enhanced permeability and retention (EPR) effect, and/or specific ligand-mediated tumor-targeting effect. Liposome is one of the most developed nanomedicines, high stability and flexible surface modification/functionalization, have been widely used in the field of drug development. Hydrophobic drugs are mainly entrapped in the liposomes by embedding in the lipid bilayers, which usually results in a low drug loading capacity that challenges their clinical transformation. In contrast, drug NCs, a nanoscale carrier-free colloidal delivery system with a theoretical drug loading capacity of up to 100%, are quite promising for poorly water-soluble drugs. However, drug NCs still face major challenges in their stability and targeted delivery. Recently, researchers from the Chinese Academy of Sciences present a novel drug delivery strategy, called nanocrystal@liposome (NC@Lipo), which integrates drug nanocrystals into the hydrophilic inner cores of liposomes and forms a hybrid core (nanocrystal)-shell (liposome) drug delivery system, merging the advantages of liposomes and drug nanocrystals to overcome these issues，for the targeted delivery of poorly watersoluble drugs. The performance of the proposed NC@Lipo delivery system was demonstrated on the drug candidate CHMFL-ABL-053 (053), which was discovered by their group. Three different 053-nanodrugs, namely 053-NC, 053-NC@PEG-Lipo, and 053-NC@FA-Lipo, were fabricated for in vitro and in vivo evaluation. In conclusion, as a proof of concept, this study showed that NC@Lipo might be a potential strategy for designing nanocrystal or liposome-based drug delivery systems with high colloidal stability, high drug loading, functionalized surface, and enhanced biological effects (including PK profile, tumor cell targeting, and in vivo antitumor efficacy). Additionally, this work may promote the development of more efficient liposome-based formulations for the delivery of poorly water-soluble drugs for commercial and clinical applications. 1. Title：Nanocrystal-loaded liposome for targeted delivery of poorly water-soluble antitumor drugs with high drug loading and stability towards efficient cancer therapy 2. Author: Huamin Liang, Fengming Zou, Qingwang Liu, Beilei Wang,...

Drug excipients not only have an effect on the manufacturing process of the drug, but also have an important influence on whether the drug has the desired effect in the human body. As the COVID-19 epidemic continues to spread around the world, coverage for COVID-19 vaccination is critical. Specific excipients play an important role in making vaccines more effective. What are the characteristics of supplying good quality COVID-19 excipients?   1. High safety performance   The main function of drugs is to cure diseases. If drug excipients as additives are used without safety evaluation, they may cause harm to human body. Especially for COVID-19 vaccine, which has not been on the market for a long time, the safety of excipients should be considered as a top priority. Therefore, to evaluate the safety of COVID-19 excipients, suppliers are required to provide safety assessment reports.   2. The performance of auxiliary materials is stable and effective   Because the COVID-19 vaccine has a wide range of injection, involves all age groups and varies in body quality, the effect of the vaccine will be greatly reduced if the stable performance of exciphants cannot be guaranteed, which is extremely detrimental to our efforts to contain the spread of COVID-19. Therefore, the performance stability should be taken as one of the key factors to evaluate whether a vaccine excipient is of good quality.   3. Strong supply capacity   At present, countries around the world are actively purchasing the new coronavirus from multiple sources, and the public are encouraged to receive the vaccine without charging for the publicity. However, the supply of vaccine production companies is still in short supply, which shows the huge demand for vaccine. Therefore, a good vaccine excipient supplier should have sufficient supply capacity to ensure that there is no shortage of product supply and can better meet the needs of vaccine manufacturers.   In conclusion, the new crown vaccine supply good quality materials with high safety performance, stable performance, effective, strong supply capacity, and other key factors, the new crown vaccine manufacturers can distinguish from the above aspects, after screening before the relevant preparatory work, so that can ensure the quality of produce vaccines have security, security hidden danger.   SINOPEG can provide high quality covid-19 vaccine excipients. Welcome to contact us.  research use only.

Osteoporosis is defined as a systemic and metabolic bone disease, which is characterized by a decrease in bone mass per unit volume and deterioration of the microstructure of bone tissue, thereby increasing bone fragility and susceptibility to fracture. With the increase in the proportion of elderly populations in the world, and in consequence the number of postmenopausal woman, sarcopenia and osteoporosis are important public health issues. Alendronate (ALN) is a kind of bisphosphonate, which is the most widely used medication in the treatment of skeletal disorders such as osteoporosis, due to its significant pharmacological effect of inhibition on bone resorption. However, the poor permeability exhibit extremely low bioavailability after oral administration (less than 1%). Furthermore, to avoid serious side effects caused by drug-food interactions, patients were instructed to take the medication orally in the morning at least 30 min before breakfast with abundant water and on an empty stomach after an overnight fast, and to remain upright for at least 30 min after dosing. To overcome the limitations of conventional treatments and provide better patient compliance, researchers from the Chinese Academy of Sciences and Zhengzhou University have jointly developed a minimally invasive procedures system for long-term injectable drug delivery, which is effective for clinical osteoporosis therapy (Scheme 1). They introduced PEGylated ALN (PEG-ALN) prodrug into the tetra-PEG hydrogel network, which limits the release rate of ALN because the PEG-ALN polymer does not move easily and freely in the 4 arm PEG hydrogel network, thus achieving slow drug release and local drug delivery, avoiding the serious side effects of systemic administration. 1. Dawei Li, Jin Zhou, Mingming Zhang, Yuanzheng Ma, Yanyu Yang,* Xue Han* and Xing Wang*. Long-term delivery of alendronate through injectable tetra-PEG hydrogel to promote osteoporosis therapy. Biomater. Sci. 2020, 8, 3138–3146.

SINOPEG are Covid-19 Vaccine Excipient Supplier. Lots of the pharmaceutical companies keep developing the Covid-19 vaccine. Now there are two famous USA Vaccines in the market, we can produce and provide main vaccine excipients and have already been one of the main supplier for one of them. Here is our Covid-19 vaccine excipients list. list: ALC-0315 = ((4-hydroxybutyl) azanediyl) bis (hexane-6,1-diyl) bis (2-hexyldecanoate), CAS no. : 2036272-55-4 ALC-0159 = 2-[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide 1,2-distearoyl-sn-glycero-3-phosphocholine, DSPC, CAS no. : 816-94-4 Polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG], mPEG2000-DMG, CAS no. : 160743-62-4 SM-102 (heptadecan-9-yl 8-((2-hydroxyethyl)(6-oxO-6-(undecyloxy) hexyl) amino) octanoate) Methoxypoly(ethylene glycol) 2000, mPEG-OH Methoxypoly (ethylene glycol) propylamine 2000, mPEG-CH2CH2CH2-NH2 Methoxypoly(ethylene glycol) carboxymethyl 2000, mPEG-CM research use only

PROTAC (proteolysis targeting chimeras) is a kind of dual functional molecules. The PROTAC molecule is composed of three parts: one end is a ligand molecule binding to the target protein to be degraded, the other side is a ligand molecule binding to the E3 ubiquitination ligase, and the middle  is connected by a specific Linker. PROTAC molecules connect the target protein to be degraded with E3 ubiquitination ligases through the above ligands, thus enabling the target protein to be ubiquitinated and further degraded by proteasomes. PROTAC, on the other hand, is not degraded by the proteasome and can be reused. Compared with common small molecule inhibitors, PROTAC molecule catalyzes protein degradation function in a way independent of occupation-driven, showing excellent high selectivity and low toxicity, and can effectively overcome the resistance of traditional small molecule inhibitors. PEG has been widely used as PROTAC Linker! The monodisperse polyethylene glycol derivative produced SINOPEG is the high quality choice of this kind of PROTAC Linker! Welcome to communicate with us!

Diabetes can lead to nonhealing chronic ulcers over tendons, bones, and joints, and such conditions have to date led to more than 20 million patients suffering a single leg amputation. It is believed that the number of patients who will require lower limb amputation annually will double by 20301. The primary cause of the dreaded and chronic diabetic ulcer complication is impaired vessel formation, particularly microvasculature formation, which is critical for the delivery of oxygen, nutrients, and growth factors, all of which are needed for wound healing, especially in the early stages. Without sufficient angiogenesis (the formation of capillary blood vessel networks), high levels of glucose accumulate at the wound site, leading to ischemia and tissue necrosis. Thus, the reestablishment of the vascular network of diabetic wounds in the early stages of healing is essential to prevent wound expansion and ulcer formation in diabetic patients. In this article, they report an injectable, self-healing coordinative hydrogel with antibacterial and angiogenic properties for diabetic wound regeneration. The hydrogel (referred to as Ag-SH-PEG) was simply prepared using coordinative crosslinking of multi-arm thiolated polyethylene glycol (SH-PEG) with silver nitrate (AgNO3) (Scheme 1a). Due to the dynamic and reversible nature of the Ag–S coordination bond, the resultant coordinative hydrogel featured self-healing properties after repeated rupture and injectable properties when applied through a medical needle. Such self-healing and injectable properties are particularly appealing for skin wound repair because they help reduce gel fragmentation and integrate ruptured gels at the target site, even after external mechanical destruction, and hence can continuously support skin wound healing. Moreover, the hydrogel network gradually releases antibacterial silver ions, which are highly attractive for use in susceptible open diabetic skin wounds. Due to the incorporation of an angiogenic drug, desferrioxamine (DFO), into the coordinative hydrogel, they finally obtained a multifunctional hydrogel that is manageable, resistant to external stress, antibacterial, and angiogenic (Scheme 1b). As an example, an irregular wound resulting from a foot ulcer is shown; in such cases, it is typically difficult for the vessels to grow in (Scheme 1c), which may be overcome in our proposed formulation. Furthermore, no self-healing hydrogels have been reported to include intrinsic structural properties that promote angiogenesis while simultaneously preventing bacterial infections. They anticipate that such unique multifunctional hydrogels will exhibit efficient anti-infective abilities, enhance angiogenic activity, and subsequently accelerate tissue healing in diabetic skin wound sites (Scheme 1d). Scheme 1 In summary, this article have described a multifunctional hydrogel scaffold with injectable, self-healing, antibacterial, and angiogenic properties for diab...

Bone regeneration is a complex process consisting of three major parts, osteogenesis, angiogenesis, and antibacterial. In the past decades, researchers have tried various approaches to guide bone regeneration, for example, some hybrid hydrogels, such as bioactive glass composited gelatin methacryloyl hydrogels, hydroxyapatite incorporated hydrogels, have been reported in guiding bone regeneration . Although enhanced osteogenic differentiation could be observed in these researches, they still fail in coordinating with angiogenesis or antibacterial effects. For now, there are still limited researches on preparing a general platform for properly combining these three parts. In this research they proposed a strategy by using injectable 4-arm-polyethylene glycol-thiol (4-arm-PEG-SH) hydrogel incorporated with liposomes-calcium phosphate nanoparticles (Lip#CaP) to synthesized one general platform in coordinating these three parts including osteogenesis, angiogenesis and antibacterial effect (denoted as ‘three-in-one' hydrogel platform). Compare to other researches, this ‘three-in-one’ hydrogel platform properly guided three process in the bone regeneration process, including the induced angiogenesis caused by the locally released DFO, enhanced osteogenesis caused by CaP-enhanced extracellular matrix mineralization, and broad spectrum antibacterial caused by the combination between Ag+ and bacterial. Additionally, this platform can be totally degraded after 8 week's implant, which avoid occupying the space for the newly generated bone. The antibacterial effect was achieved by Ag+ largely avoiding the antibiotic resistance caused by antibiotics. 1. Chen, H., Cheng, R., Zhao, X., Zhang, Y., Tam, A., & Yan, Y. et al. (2019). An injectable self-healing coordinative hydrogel with antibacterial and angiogenic properties for diabetic skin wound repair. NPG Asia Materials, 11(1). doi: 10.1038/s41427-018-0103-9 If there is any copyright infringement, please contact us and we will remove the content at the first time. Sinopeg provide various NW poly(ethylene glycol) (PEG) products: 2KDa, 5KDa, 10KDa, 20KDa, etc. Products: Linear Monofunctional PEGs Linear Bifunctional PEGs Linear Heterofunctional PEGs Branched PEGs Multi-Arm Functional PEGs Functionally Grafted PEGs