Team:Shanghai City/Results
Result
What did we complete?
1. The first encryption level
(1) We adopted the method corresponding to the password table, and write a software for encoding and decoding (see model).
(2) We thought it could be further strengthened, for example combining with AES.
2. The second encryption level
We hide a meaningful piece of DNA in genomic DNA, then decoded it by polymerase chain reaction (PCR) using a pair of primers (keys), and then sequenced.
3. The third encryption level
(1) Encryption: we perform asymmetric secret key encryption similar to computer encryption on two primers (see model).
(2) Steganography: on the basis of CADS encryption method (long primers not done), add more complex information interference items, including single and double stranded DNA, etc (Yes, we did it).
4. The fourth encryption level
The DNA is stored on paper, making it harder for a thief to decipher. As far as I know, this is the first time DNA has been used for encryption on paper.
Part 1
1. The first encryption level
We adopted the method corresponding to the password table, and wrote a software for encoding and decoding (detail information please see model).
2. The second encryption level
We hide a meaningful piece of DNA in genomic DNA (HEK 293T), then decoded it by polymerase chain reaction (PCR) using a pair of primers (keys), and then sequenced.
Divide the solution into 12 tubules, in which each of the 6 tubes contains 24 ul, labeled as 7-12, and the other 6 tubes each contains 48ul, labeled as 1-6.
The PCR fragment sequencing
3. The third encryption level
(1) Encryption: we perform asymmetric secret key encryption similar to computer encryption on two primers (detail information please see model).
(2) Steganography: on the basis of CADS encryption method (long primers not done), add more complex information interference items, including single and double stranded DNA, etc (Yes, we did it).
The primers were mixed with other false primers, so before PCR reaction, Cas12a reaction should be performed.
The true information is 164-bp DNA fragment, and the false is 465-bp. After we adjusted the reation condition, we get the right information DNA fragment (164-bp in right panel).
The primers were mixed with other other false primers and false dsDNA, so before PCR reaction, Cas12a reaction should be performed, and even need to add Dnase I.
As can be seen from the figure, in the 6-10 without adding DNA enzyme I (right), due to the interference of double-stranded DNA, no distinct bands could be amplified (164-bp). In the 1-5 added with DNA enzyme I (left), due to the degradation of double-stranded DNA by DNA enzyme I.
4. The fourth encryption level
The DNA is stored on paper, making it harder for a thief to decipher. As far as I know, this is the first time DNA has been used for encryption on paper.
DNA storing on paper& Decoding by PCR
Introduction
Store the DNA on the paper. After dropped on the paper, the DNA solution will evaporate and DNA inside which is kept on the paper. As it is hard to test out whether or not there is DNA on a certain paper, this method for storing DNA is safe. What’s more, paper is cheap and normal, which means everyone can get and carry it easily. Additionally, DNA has a high solubility, which means that as long as recipients immerse the paper they get into water, the DNA can solve into it and become solution state again, which is easy for the recipients to extract and test.
Our target is to find out whether storing DNA on paper is practical and which kind of paper, which way to store the DNA can have the best effect.
Experimental group:
Experimental results:
From the results of glue running, it can be seen in figure that groups 3,6 and 7, namely, stored DNA best in paper jam (white), IGEM sticker and solution.
Experiment reflection:
The brightness of electrophoretic bands is limited by many factors. The reason for the difficulty in storing DNA in groups 1 and 2, the white and yellow notebooks, may be that the notebook pages have a low water absorption capacity, making it difficult for DNA to adhere to the paper. However, in group 5, the DNA storage paper group, the dark band may be due to the strong water absorption of the DNA storage paper, resulting in a small amount of residual solution, which leads to the insignificant band of electrophoresis.