Every month, a research paper reporting a new bioink or modification of an existing one is published. All these new options provide increasingly more specialized materials for specific applications. However, their use cases often are limited. Thus, when you are starting your bioprinting project, it might be difficult to navigate the bioink landscape and decide which material will be best to start with. In this article, we present our top five biomaterials that have a wide range of applications and compatibility with different cell types – something that will get you going in no time!
We start our list with Pluronic 127 – something very different from other picks on our list. Pluronic 127 is a synthetic copolymer that is used mostly as a sacrificial or support biomaterial. As such, it is not used in a direct combination with cells. However, it has a very important place in bioprinting.
Many bioinks lack the rheological properties needed to keep their 3D shape together after deposition – Pluronic 127 can come in handy is this scenario. You can create walls made of Pluronic that will physically support problematic hydrogel, keeping everything in place until crosslinking kicks in. Due to its gelation mechanism, which creates a reversible gel at 4 °C, it is possible to 3D print temporary structures that can be removed later with a cold buffer. You can also create channels and immerse them in another target hydrogel. After the latter solidifies, you can evacuate the Pluronic to obtain hollow channels inside your constructs – an easy recipe for introducing vascular-like structures into your model.
A bonus tip for Pluronic is to use it as training material. This cheap and easy-to-use hydrogel is optimal to practice bioprinting and test different shapes. Instead of wasting more expensive bioinks, try all the functions of your bioprinter with Pluronic, or print your new 3D model with this material to confirm the right geometry before you start an actual experiment.
Gelatin-Methacryloyl (GelMA) had to make it to our list. This naturally derived bioink is one of the most popular materials used in 3D bioprinting. It has earned its position thanks to great biological and mechanical properties. GelMA contains cell-binding motifs, making it compatible with a variety of cell types. Fibroblasts, mesenchymal stem cells, myoblasts, chondrocytes, and many more were successfully used in combination with this hydrogel to create 3D tissue models.
Thanks to special chemical modification, GelMA can be crosslinked using light – blue or UV depending on the crosslinker added. This feature allows you to bioprint GelMA directly and crosslink it on the go, and to use techniques such as coaxial bioprinting to create sophisticated 3D shapes. Photocrosslinking also means a possibility to fine-tune the properties of the resulting hydrogel. By adjusting the ratio of the gel to the crosslinker and the duration of light exposure, you can achieve constructs with different stiffness.
As a versatile bioink, GelMA found applications not only in tissue engineering but also in cell signaling research, bio-sensing, and gene delivery. If you are interested in using it for your next bioprinting project, check out our detailed guide about GelMA.
You might recognize sodium alginate from another field – cooking! This polysaccharide, besides being a great ingredient for fancy desserts, is widely used in laboratories around the world for cell encapsulation and bioprinting. Sodium alginate can form a hydrogel when exposed to divalent cations such as Ca2+ or Br2+. Even though it doesn’t provide any specific cell-binding sites, it can create a great and soft 3D environment for embedding cells. However, if you require better biological stimulation, you can chemically modify it (i.e.: with RGD for cell adhesion) or simply mix it with functional additives.
Sodium alginate is very easy to mix with cells at lower concentrations, but this also means it’s rather liquid during printing. Fortunately, printing it can be a breeze thanks to the FRESH bioprinting technique. This special deposition method provides physical support during the print until sodium alginate is crosslinked and ready to be released.
Low cost and low toxicity are the key features that make sodium alginate one of the most interesting biomaterials. Use it alone or in combination with other polymers to achieve unique properties suitable for your bioprinting project. Don’t miss our dedicated guide for sodium alginate to learn more details about it.
This collagen based bioink could not be missed in our recommendations. As one of the most abundant ECM proteins in native tissue – collagen is a perfect base for an excellent bioink. If you care about biocompatibility, printability, remodelling capabilities and mechanical strength – Lifeink 200 should be in your toolbox.
Combined with the FRESH bioprinting method, Lifeink 200 can be printed into sophisticated 3D shapes, creating robust constructs that support cell survival and growth. Its neutral pH and physiological salt concentration make Lifeink 200 cell-friendly and convenient to use.
If you had problems with other collagen-based hydrogels in the past – don’t worry. We created an optimized protocol for working with Lifeink 200. Just follow it and you will achieve the results you were looking for.
Hyaluronic acid (HA) is another abundant component present in different tissues in the body – from skin, to cartilage, to brain. It not only provides cell attachment but also regulates processes such as migration, differentiation, and proliferation. So if you need biologically relevant scaffolds that can also enhance cell signaling – PhotoHA might be the right choice.
The prefix “photo” in its name means you can crosslink PhotoHA with light. For example, using LAP as a crosslinker and blue light on any of the Allevi bioprinters, you can easily create 3D models consisting of HA. Another advantage of PhotoHA is that it is translucent, so if you plan on checking your bioprinted constructs under a microscope – PhotoHA will minimize problems with light penetration.
All the biomaterials described above can be easily printed on Allevi bioprinters. Our versatile system makes it easy to use any extrudable hydrogel with great precision and high speed. There’s no need to optimize printing parameters for these hydrogels – we have done it already for you! Our software will help you decide on the most optimal conditions for printing. But if you are creating something custom and need our help – don’t hesitate to contact us at [email protected]. Is there anything that you think should make it to our top 5 list? Let us know!