After Wu Hao's words fell, everyone present nodded in approval. The difficulty of 3D printing technology is still printing. How to print out precise organs and tissues is the biggest problem facing all scientific researchers.

If you want to print out precise organs and tissues, you must have a very thorough understanding of the organs and tissues. Only by understanding the composition of organs and tissues, as fine as the rehearsal combination of each cell, can the printed organs and tissues remain active, survive in the patient's body, and perfectly replace the functions of the original organs and tissues.

To understand the rehearsal composition of each cell in an organ tissue, it is necessary to conduct a fully detailed study of human organs. Although there are some mature research materials in the world, it needs to be refined to the order of cell permutation and combination. Obviously no one can achieve this kind of work. Therefore, the most important task before Wu Hao and the others is to have each one. Detailed and precise digital model data of organs. Only when the digital model of this fine organ is built, can biological 3D printing be realized.

This is like an ordinary 3D printer before printing an object, it needs to build a 3D model that needs to be printed on the computer. Only when the 3D model data is imported, the 3D printer can print out the corresponding model.

The principle of biological 3D printers is the same, but it is much more complicated than ordinary 3D printers, and the difficulty will also be increased geometrically.

First of all, the model printed by an ordinary 3D printer is actually resolved and decomposed, and the interior generally presents a honeycomb or hollow structure, and only the outer shell is retained. The advantage of this is to greatly reduce the consumption of consumables and save costs. Secondly, because the cross-section of the printing is less, the printing speed will also be increased a lot.

Although the printing time of this kind of 3D printer is very slow, if the hollow part is filled, the printing time will be increased several times.

Secondly, 3D printers, whether they are ordinary additive 3D printers or light-curing 3D printers, have such a data as printing accuracy. Limited by the hardware level and software level of 3D printers, the printing accuracy of 3D printers is also different. Good printer hardware and software are excellent, so the printing accuracy will naturally go up. In order to save money, cheap printers shrink the quality of hardware and software, so the printing accuracy is not so high. This is also reflected in the fineness of the printed objects. The surface of the objects printed by a good 3D printer is smooth and delicate. The surface of the object printed by the 3D printer with poor quality will be very rough, and even show a spiral texture of annual rings, which is the trace of additive printing.

Secondly, printing accuracy is also related to printing time. The higher the printing accuracy of a 3D printer, the longer it will take. On the contrary, the lower the printing accuracy, the faster the time.

As for biological 3D printers, these problems need to be solved one by one. The first is that the printed organ tissues must be printed in strict accordance with the fine digital organ model data, and there must be no deviation. This requires that the entire biological 3D printer must have high enough precision to be able to print micron-level cells.

Secondly, it must be a one-to-one solid organ tissue. It cannot be printed out with an empty shell like an ordinary 3D printer. This is definitely not acceptable.

Then there is the printing time, which is very important in the printing of organs and tissues with biological 3D printers. It is necessary to ensure a faster printing speed while ensuring sufficient precision printing.

We must know that the cells in the human body are not static, but change all the time. Cells continue to age and die at the same time as they continue to regenerate. The cell life span varies. Intestinal mucosal cells have a lifespan of 3 days, liver cells have a lifespan of 150 days, taste bud cells have a lifespan of 10 days, and nail cells have a lifespan of 6 to 10 months. The brain, bone marrow, and nerves in the eyes The life span of a cell is several decades, which is almost the same as the life span of a human body, and some white blood cells in the blood can only live for a few hours.

These cells are alternately undergoing renewal metabolism, so as to realize the renewal of organ tissue cells, which requires that the entire printing time must be rapid. It should not take too long just to ensure accuracy. If the printing time is too long, the printed organs and tissues will lose their activity and become a piece of dead flesh, which has no medical value.

Therefore, in biological 3D printing, time is also one of the important problems that researchers must overcome.

The last and most difficult technique is how to ensure the vitality of printed organs. Even if it is fast printing, it takes dozens to hundreds of hours to print a complete organ tissue. How to ensure the vitality of the printed organ tissues? This is this One of the most critical issues in technology.

If this problem cannot be solved, then the entire project will fail, and the print out will be a piece of dead meat, without any medical value at all.

Not only does the printing process and the printed organs and tissues remain active, but also the consumables needed for printing, that is, the activity of the cells. Only living cells can print out living organs. If the cell is dead, it must be a piece of dead flesh printed.

This technology is very difficult. It is necessary to ensure that all cells are healthy and viable. If there are more necrotic cells in it, it will also affect the quality of the printed organs, and even the survival rate and functional integrity.

Moreover, these cells have to go through the printing process. How to ensure the survival rate of these cells is also an important problem for researchers~lightnovelpub.net~ In fact, the problems in this technology are far from these. There are many, many. Even some issues that are not usually important can become the key to the neck.

For another example, the types of organs and tissues are different, and the tissue structure is different. Although they are all composed of cells, the appearance of cells and the arrangement and combination of cells are also very different. The organization presented by different permutations and combinations is also different.

For example, how to print the important blood vessel network in organs, how to print the grease part, and how to print the cartilage part, etc.

So this biological 3D printer may not only be able to achieve a printing nozzle, but it may also be able to print with a variety of nozzles alternately. And it is impossible to try only one type of consumable (cells), you may need to prepare several consumables (consumables), so as to meet the printing needs of different parts of the organ tissue.

In this way, high-precision imitation printing of these human organs and tissues can be achieved, and healthy printed organs that meet the standards of medical transplantation can be obtained, which can be transplanted into the patient's body and continue the life of the patient.