1. A preparation method of an antibacterial cornea repair material, wherein the method includes the following steps:
(1) purifying type I collagen extracted from beef tendons, and using an acetic acid or hydrochloric acid solution to prepare a collagen solution with a concentration of 6.0-10.0 mgmL;
(2) casting the collagen solution into the forming mould of the cornea repair material, and then naturally air drying at room temperature to form a membrane;
(3) soaking the collagen membrane obtained in step (2) in an antibiotic solution with a concentration of 5.0-25.0 mgmL, and stirring until the membrane is fully in contact with the solution; and then adding a crosslinking agent and a catalyst to the above-mentioned solution, and stirring to perform a crosslinking reaction; the mass ratio of the crosslinking agent to the catalyst is 4:1, and the mass ratio of the total of the collagen and antibiotics to the crosslinking agent is (5-7):1; and
(4) taking out the crosslinked membrane material obtained in step (3) and washing 3-5 times with deionized water, and then naturally air drying at room temperature to obtain the antibacterial cornea repair material.
2. The preparation method according to claim 1, wherein the forming mould of the cornea repair material in step (2) has a similar geometrical shape to the cornea tissue.
3. The preparation method according to claim 1, wherein the concentration of the antibiotics in step (3) is 10.0-15.0 mgmL.
4. The preparation method according to claim 1, wherein the antibiotics in step (3) are tobramycin, gentamicin, ofloxacin or ciprofloxacin.
5. The preparation method according to claim 1, wherein the crosslinking agent in step (3) is 1-ethyl-3(3-dimethylaminopropyl)carbodiimide, and the catalyst is N-hydroxysuccinimide.
6. The preparation method according to claim 1, wherein the mass ratio of the total of the collagen and antibiotics to the crosslinking agent is 6:1.
7. The preparation method according to claim 1, wherein the crosslinking reaction time in step (3) is 2-6 hours.
8. An antibacterial cornea repair material prepared by the method according to claim 1.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process for catalytic cracking of a hydrocarbon feedstock comprising contacting the feedstock with a catalyst composition comprising a porous crystalline material which contains at least one channel system, in which each channel is defined by a 12-membered ring of tetrahedrally coordinated atoms, and at least two further, independent channel systems, in each of which each channel is defined by a 10-membered ring of tetrahedrally coordinated atoms, wherein the number of unique 10-membered ring channels is twice the number of 12-membered ring channels.
2. The process of claim 1 wherein said porous crystalline material contains one 12-membered ring channel system and two 10-membered ring channel systems.
3. The process of claim 2 in which the channels in each 10-membered ring channel system of crystalline material extend in a direction generally perpendicular to the channels in the other 10-membered ring channel system and to the channels in the 12-membered ring channel system.
4. A process for catalytic cracking of a hydrocarbon feedstock comprising contacting the feedstock with a catalyst composition comprising a synthetic porous crystalline material comprising a framework of tetrahedral atoms bridged by oxygen atoms, the tetrahedral atom framework being defined by a unit cell with atomic coordinates in nanometers shown in Table 1, wherein each coordinate position may vary within \xb10.05 nanometer.
5. A process for catalytic cracking of a hydrocarbon feedstock comprising contacting the feedstock with a catalyst composition comprising a synthetic porous crystalline material characterized by an X-ray diffraction pattern including values substantially as set forth in Table 2 of the specification and having a composition comprising the molar relationship
X2O3:(n)YO2,
wherein n is at least 5, X is a trivalent element, and Y is a tetravalent element.
6. The process of claim 5 wherein X is a trivalent element selected from the group consisting of boron, iron, indium, gallium, aluminum, and a combination thereof; and Y is a tetravalent element selected from the group consisting of silicon, tin, titanium, germanium, and a combination thereof.
7. The process of claim 5 wherein X comprises aluminum and Y comprises silicon.
8. The process of claim 5, wherein the catalyst composition also comprises a large pore molecular sieve having a pore size greater than 7 Angstrom.
9. The process of claim 8, wherein the large pore molecular sieve is zeolite Y.
10. The process of claim 8, wherein the weight ratio of said synthetic porous crystalline material to the large pore molecular sieve is from 0.005 to 0.50.