VitroGel™3D 即用型水凝胶FAQ-General Questions

VitroGel®

Technical Tips and Frequently Asked Questions (FAQ)

 

GENERAL

 

Q What is VitroGel ?

A VitroGel® is a xeno-free functional hydrogel system that closely mimics the natural extracellular matrix (ECM) environment. Modified with multiple cellular functional ligands, VitroGel allows for a robust 3D cell culture platform and can be used as an injectable delivery system for drug discovery, tissue engineering, cell therapy, and personalized medicine.

VitroGel comes in two different variations, ready-to-use and high concentration.

The ready-to-use VitroGel is a series of user-friendly functional hydrogels offering an excellent balance of simplicity and versatility. The hydrogels have optimized formulations of multi-functional ligands and concentration. The hydrogel solution is stable at room temperature and can mix with cells/culture medium directly to use.

VitroGel High Concentration hydrogels give scientists the full control to adjust both mechanical strength and functional ligands of the cell culture environment. The high concentration formulation allows the maximum flexibility to manipulate the mechanical strength of hydrogel by adjust the dilution ratios of the hydrogel solution. VitroGel High Concentration Hydrogels also can use as a set of building blocks to create a functional micro-environment by blending (“mix and match”) different versions.

 

 

Q Which VitroGel hydrogel product should I choose?

A Ready-To-Use Hydrogel

For many users, this is the preferred hydrogel system for many applications. It is a ready-to-use hydrogel where you need only to add your cells, cover medium, and incubate. The hydrogels come with different versions of optimized formulations for different cell types and applications: It is a ready-to-use hydrogel where you need only to add your cells, cover medium, and incubate.

• VitroGel Hydrogel Matrix (SKU: VHM01): a general-purpose hydrogel that is good for many cell lines and primary cells. This hydrogel can support the formation of tumor spheroid, the cellular network structure of stromal or fibroblast cells, co-culture, invasion or 3D cell migration.

• VitroGel ORGANOID (SKU: VHM04): supports a wide range of organoids from patient-derived samples, stem cells, tissues, co-culture and PDX resources.

• VitroGel STEM (SKU: VHM02): generate high-quality 3D stem cells directly from liquid nitrogen. Excellent for stem cell expansion, 3D scale-up or downstream applications.

• VitroGel MSC (SKU: VHM03): support 2D hydrogel coating, 3D cultures of mesenchymalstem cells (MSCs) and make hydrogel cell beads to replace microcarrier for MSC scaleup.

• VitroGel HEK293 (SKU: VHM05): support 3D culture and scale up of human embryonickidney 293 (HEK293) cells for cell-based bioproduction.

• VitroGel Angiogenesis Assay Kit (VHM06-K1): a revolutionary tool for researchers to study the effect of both hydrogel properties and culture medium onangiogenesis process.

 

High Concentration Hydrogels

For more advanced users, the VitroGel High Concentration hydrogels give scientists full controlto manipulate the biophysical and biological properties of the cell culture environment. We have many types of hydrogel with different binding ligands, making our system a “Mix and Match”where you can control what is in the hydrogel for your 3D cell culture. All the high concentration hydrogels come with VitroGel Dilution Solutions to adjust the final hydrogel strength from 10 to 4000 Pa. Customized hydrogels can reach more than 20,000 Pa.

• VitroGel® 3D High Concentration Kit (SKU: TWG001) is a pure and unmodified hydrogel that allows the maximum flexibility to manipulate the 3D cell culture environment for different needs. The unmodified hydrogel matrix structure is good for cell spheroid formation, suspension cells, or cells requiring low cell-matrix interactions.

• VitroGel® RGD High Concentration Kit (SKU: TWG003) is modified with a high concentration of RGD cell adhesive peptides, promoting the cell attachment and cellmatrix interactions during the 3D cell culture. It can achieve high levels of integrinbinding activities to promote intercellular networks even after hydrogel dilution.

• VitroGel® COL High Concentration Kit (SKU: TWG009) is modified with collagen-mimetic peptide, which specifically binds the integrin α2β1, promoting many bioactivities such as osteoblastic differentiation in vitro and enhancing osteoblastic activity in vivo.

• VitroGel^® IKVAV High Concentration Kit (SKU: TWG007) is modified with laminin-derived functional peptide, which is actively involved in different biological activities such as neuronal progenitor cell differentiation, promoting cell adhesion, neurite outgrowth, angiogenesis, and tumor growth.

• VitroGel^® YIGSR High Concentration Kit (SKU: TWG008) is modified with laminin-derived functional peptide, which involves endothelial cell adhesion, cell proliferation, and motility/migration.

• VitroGel^® MMP High Concentration Kit (SKU: TWG010) is modified with Matrix Metalloproteinases (MMP) for a biodegradability matrix.

We can customize our hydrogels with different functional ligands. Please contact at support@thewellbio.com if you need a customized product.

If you need help finding the right hydrogel product for your research project, please fill this product help form.

 

Q What is the chemical composition of the VitroGel?

A The hydrogel is a xeno-free synthetic polysaccharide-based hydrogel system.

 

Q What is the difference between VitroGel Dilution Solution Type 1 and Type 2?

A VitroGel Dilution Solution Type 1 contains sucrose to maintain the best osmolarity. Dilution Type 2 is sucrose-free. For most cell lines, VitroGel Dilution Solution Type 1 is recommended.

VitroGel Dilution Solution Type 2 is for scientists working with cells that are sensitive to sugar.

 

Q Does VitroGel have viscoelastic properties?

A Yes, all VitroGel hydrogels are tested with a dynamic rheometer for viscoelastic properties. For VitroGel High Concentration hydrogels, the elastic modulus (G’) can be adjusted from 10 to 4,000 Pa by changing the hydrogel concentration with the VitroGel Dilution Solution.

 

Q Does VitroGel contain any natural ECM proteins like fibronectin, collagens, or laminins?

A VitroGel does not contain any natural ECM proteins. Scientists can add growth factors and proteins to the hydrogel system for a well-defined system.

 

Q What is the mechanical property of VitroGel? Can I adjust the stiffness?

A We test the elastic modulus (G’) of VitroGel with a dynamic rheometer. The G’ is dependent on the hydrogel dilution and the cell culture medium used. The G’ of non-diluted VitroGel High Concentration is around 4,000 Pa. If a higher hydrogel strength is required, please contact us at support@thewellbio.com for a customized hydrogel that can reach over 20k Pa. You can also check our BioInk product (VitroINK), which can reach the G’ over 45k Pa.

 

Q What is the difference between hydrogel elastic modulus and hydrogel stiffness?

A We use the elastic modulus (G’) to represent the strength of VitroGel, which is tested by a dynamic rheometer. A simple conversion between the elastic modulus and stiffness is to calculate at 1:3 ratio. Fox example, if the hydrogel is 100 Pa in G’, which is equal to 300 Pa in stiffness. Therefore, the 4000 Pa G’ of VitroGel High Concentration is around 12,000 Pa in stiffness.

 

Q Will adjusting the temperature induce the hydrogel formation of VitroGel?

A Adjusting the temperature will not induce the hydrogel formation. VitroGel can maintain the liquid form at room temperature. The hydrogel formation can be induced by mixing with an ionic solution such as a cell culture medium. Increasing the temperature would reduce the viscosity of the hydrogel solution.

 

Q Can molecules penetrate or diffuse through VitroGel?

A Yes, VitroGel supports the diffusion of molecules of different sizes from small molecules to big proteins (e.g., IgG). Drug compounds, antibodies, staining dyes can be added on the cover medium to penetrate the hydrogel. VitroGel can be mixed with molecules for control release experiments.

 

Q Does VitroGel have autofluorescence?

A VitroGel is a xeno-free system. We do not detect any autofluorescence in our various imaging tests. We recommend that scientists perform a control experiment to determine background fluorescence.

 

Q Can I harvest cells after culturing with VitroGel?

A Yes, scientists can easily harvest cells with our enzyme-free, ready-to-use VitroGel Cell Recovery Solution in 20 minutes. VitroGel Cell Recovery Solution is room temperature stable with a neutral pH and has a operating temperature of 37°C. The cell harvesting solution can maintain high cell viability during the recovery process. Harvested cells can be further sub-cultured for both 2D and 3D.

Additional information can be found here.

 

 

Q Can VitroGel be used for both 3D culture and 2D hydrogel coating?

A Yes, VitroGel can support 3D cell culture, 2D thick gel coating and 2D thin gel coating culture. Embedding cells in the hydrogel matrix (3D cell culture) can maximize the cell-matrix interaction and potential cell-cell communication in response to different biophysical and biological properties of the hydrogel. Some cells are hard to culture in 3D and as a result, 2D coating is an alternative method for cell culture.

2D thick gel coating uses a layer of hydrogel to change the properties of the substance. It is a method between the traditional 2D culture and the true 3D cell culture. 2D thick gel coating is an alternative approach if scientists do not want to jump into 3D cell culture but want to see how cells behave differently based on different substances. It is also a good method for layer-bylayer co-culture as well.

2D thin gel coating is used as a thin layer of hydrogel to change the surface properties of the substance, which may change the capability for cell attachment but not the stiffness of the substance.

 

 

Q Which culture method should I choose?

A VitroGel hydrogel system is versatile for many applications. The hydrogel is flexible for multiple culture methods such as 3D cell culture, 2D hydrogel coating, static suspension culture, hydrogel-cell bead, and used as an injectable carrier.

• 3D cell culture: make a full cellular encapsulation in the hydrogel matrix and enhance the cellhydrogel matrix interactions.

• 2D hydrogel coating: allow cells to interact with/submerge into the functional hydrogel substance and maintain an excellence exposing surface to the top medium. This method is great to generate the bridge between the traditional 2D culture and 3D cellular encapsulation culture.

• Static suspension culture: this is a unique culture method of VitroGel hydrogel system. By simply mixing the VitroGel solution and cells for a soft hydrogel formation, the researchers can further directly mix the hydrogel-cell mixture with additional culture medium to make a hydrogel-cell suspension. This method is great for suspension culture and scale up.

• Hydrogel-cell bead: The hydrogel solution can mix with cells for a soft hydrogel, which then can add to the cell culture medium as droplets for hydrogel-cell bead formation. This culture method not only encapsulates cells within the hydrogel matrix to enhance cell-matrix interactions, but also allow the whole hydrogel-cell bead to suspense in cell culture medium for optimal medium penetration. Researchers can adjust the size of the hydrogel beads by changing the volume of droplets added to the culture medium.

• Injectable carrier: Simply mix hydrogel solution with cells/compounds at room temperature, the hydrogel is ready for injection in 20 minutes. Under the mechanical shearing force such as injection through a syringe, the hydrogel performs a gel-sol transition and becomes free-flowing status. However, once the shearing force ceased, the mechanical strength of the hydrogel can rapidly recover with a sol-gel transition and become a hydrogel status again. With this injectable property, VitroGel can be used for in vivo cells/drug delivery for cell therapy or controlled release.

 

 

Q Is VitroGel biocompatible for in vivo study?

A Yes, VitroGel is biocompatible and safe for animal study.

 

Q How long can cells be grown in the VitroGel system?

A We have tested the growth of cells in the hydrogel system for more than eight weeks.

Depending on the cell type and application, the 3D cell culture can last even longer. Scientists may need to change the cover media more frequently once the number and size of cells increases.

 

Q Is there a specific type of cell culture plate that should be used?

A No specific plate is required. Any regular tissue culture treated plate can be used.

 

Q What is the pore size of VitroGel?

A The pore size of VitroGel is about 200-500 nm. The hydrogel is flexible, soft, so the cells can push the hydrogel matrix out and molecules can easily penetrate through the hydrogel matrix.

 

Q What is the elastic modulus of ready-to-use gels?

A The elastic modulus of the ready-to-use VitroGel is about 100-300 Pa. Please keep in mind, the elastic modulus (G’) was tested by dynamic rheometer. The G’ is different than stiffness (Young’s modulus). A simple conversion between G’ and stiffness is 1:3 (100 Pa of G’ is about 300 Pa of stiffness). Therefore, the stiffness of ready-to-use VitroGel is about 300-900 Pa.

 

Q What is the elastic modulus of the high concentration/different dilution VitroGels?

A For VitroGel High Concentration hydrogels, the elastic modulus (G’) can be adjusted from 10 to 4,000 Pa by changing the hydrogel concentration with the VitroGel Dilution Solution. The G’ is about 4000 Pa at 1:0 dilution, 1200-2000 Pa at 1:1 dilution, 600-1000 Pa at 1:2 dilution, 200–500 Pa at 1:3 dilution, and < 500 Pa at dilution higher than 1:3.

 

Q What is the difference between VitroGel ORGANOID versions?

A The VitroGel ORGANOID has four different version which were formulated with various biofunctional ligands, mechanical strengths, and degradability to fulfill the needs of different organoid culture conditions.

 

Q What are the different mechanical strengths between VitroGel ORGANOID versions?

A The mechanical strengths of different VitroGel ORGANOID hydrogel are in this order:

VitroGel ORGANOID-3 > VitroGel ORGANOID-4 ≥ VitroGel ORGANOID-2 > VitroGel ORGANOID-1.

 

Q Which VitroGel ORGANOID hydrogel should I choose for my organoid type?

A The VitroGel ORGANOID Discovery Kit includes four different formulations of VitroGel ORGANOID hydrogels, type 1-4, which have various bio-functional ligands, mechanical strengths, and degradability to fulfill the needs of different organoid culture conditions. Because there are a wide range of cell resources for organoids from stem cells, patient-derived tissue, co-culture, and PDX, it is hard to tell which organoid hydrogel would be best for the researcher’s experiment. Therefore, the discovery kit helps perform a quick screening of 4 different formulations and determine the best version for moving on. From our findings, versions 1, 2, or 3 are suitable for gastric organoids. Versions 1 or 3 are suitable for lung organoids. Versions 2 or 3 are suitable for brain organoids, and versions 3 or 4 are suitable for cancer organoids. By saying that, we would still suggest you using the Discovery kit to make a quick screening and find the hydrogel that can fulfill your research goal best.