Coroner Coroner

All modern investigations rely on evidence, and flies are far from reliable evidence.

but…

Lin Xinyi never thought of using flies as conclusive evidence pointing to the murderer.

Flying flies to find blood is just a screening method that he took out to identify suspects as soon as possible from more than 100 people when he had to and limited time.

According to his thinking, there may be several passengers in the crowd who can attract flies.

But this has no effect. As long as the few passengers surrounded by flies stay and take them to the Metropolitan Police Department for a Lumino occult blood test one by one, he can further confirm who is the murderer.

But now, among more than 100 people, there is only one who is liked by flies.

There is no need to wait for the next inspection result, the murderer is basically him.

"Don't be stubborn anymore."

"Whether you got blood or icing sugar, science will tell us the answer."

Lin Xin could see at a glance that the suspect probably didn't know about Lumino's existence, so there was still a little bit of luck.

So, he simply explained what the Lumino reaction was in front of everyone.

"This... can, find a reagent for diluting blood stains?"

Hearing this, the young man's voice trembled slightly.

But after his eyes fluctuated, he still answered calmly and clearly:

"That doesn't mean anything!"

"I only had a nosebleed in the morning when I rubbed it with my hands."

"So even if the blood is tested from me, it can't prove that I murdered at all, right?"

The more he spoke, the firmer his tone became, and in the end he even put on an expression of indignation, as if he had been wronged too much.

"this is very simple."

It was not Lin Xinyi who spoke, but the great detective Kudo who was almost forgotten by everyone:

"Since the murderer is locked, the evidence is not difficult to find."

"The murderer's purpose at the time was robbery, and all the cash in the deceased's wallet disappeared."

"Most of the deceased's cash is now on the murderer's body, so as long as you send all the banknotes on your body for inspection to see if there are fingerprints and dander left by the deceased on it, you can confirm whether the murderer is you!"

Kudo Shinichi stood up confidently.

He has never played 100 out of 1, and now 1v1 should always be where he is good at.

But the young man who was regarded as the murderer showed a smile of "I knew it":

"It makes sense!"

"Then check it out - I only have so much money on my body, you all take it and check it!"

"If you can't find any fingerprints and dander, you have to apologize to me with the soil!"

Saying that, he took out a few coins with pitiful denominations directly from his shoulder bag and displayed them generously in front of everyone.

"This..." Kudo Shinichi smiled stiffly:

The murderer was clearly prepared.

He probably realized he might be under investigation after being forcibly sealed off at the scene.

So, this guy secretly hid the stolen money in an inconspicuous place on the platform, and was going to find a way to go back and get it after the investigation was over.

It may be hidden in the trash can, or it may be a vending machine. In short, there must be no banknotes stolen from the deceased left on him now.

Moreover, judging by how well-prepared and fearless this guy was, he was afraid that when he touched the banknotes, he would always wrap it in clothes, and maybe he didn't even leave his fingerprints on it.

this bastard...

If you don't use your brain to think of a complicated murder trick, all your thoughts are spent on cleaning up the traces.

How can you be so ignorant?

Mr. Holmes of Heisei was a little depressed.

This was indeed the type of prisoner he had never dealt with, and it was an unexpected headache.

"No... This guy can't possibly notice everything!"

"Watch carefully... Maybe there will be a breakthrough point."

Kudo Shinichi was full of energy, ready to fight the prisoner's wits.

But... Lin Xinyi said again:

"that…"

"Does this require finding evidence elsewhere?"

"Do you think that there is no way to identify DNA by washing the diluted blood stains, and only blood stains that can be seen with the naked eye can identify DNA?"

"Do you feel that the bloodstains are too small to be seen by the naked eye, and the forensic doctor can't extract the test?"

Lin Xinyi said with a strange expression.

"Er?" The young man's expression changed: "What, what did you say..."

"So trace of blood, can DNA also be detected?"

"of course can."

Lin Xinyi looked at the murderer as if he were watching a clown performing poorly:

"The extraction and purification of DNA from trace samples has always been the focus of forensic evidence research."

"And the luminol reaction doesn't interfere with DNA extraction."

"So, as long as you do the luminol occult blood test on you, and then remove a certain amount of blood-stained dander from the part that shows blue fluorescence, you can easily identify who the blood belongs to."

Occult blood samples contain very little bloodstains. Conventional DNA extraction methods are limited by the volume of the carrier and cannot obtain the amount of template DNA required for PCR amplification. It is indeed difficult to obtain better DNA typing.

But this is not a problem at all. DNA purification and extraction technology for trace samples can be of great help.

For example, the nucleic acid purification technology by magnetic bead method uses nano-scale magnetic beads. The surface of the magnetic beads is labeled with a functional group that can react with nucleic acids.

In addition, there is also a column purification method. The nucleic acid purification column used in this technology uses a silica gel membrane as a specific adsorption material for nucleic acid, and basically does not adsorb other biological materials, which can ensure the maximum recovery of DNA RNA in the sample and remove other impurities at the same time. .

These technologies will be mature enough to be made into ready-made purification and extraction kits in the future, as long as you buy them back and follow the instructions step by step.

Of course, Lin Xinyi is not quite sure whether these technologies have been put into use in 96.

Speaking of which, DNA testing was only used in criminal investigations in 84, so DNA purification technology may still be a cutting-edge technology that has not been put into actual combat.

"You should find an opportunity to learn from Shiho Miyano..."

"She's a biologist and should know better than me."

Lin Xin only uses technology, not research technology.

Just like the excavator driver does not know much about the development history of excavator equipment, he does not know much in this regard.

But even if it has not been put into use, it doesn't matter. The big deal is to collect the blood-stained samples from the murderer and store them for 10 years before checking.

During this period of time, biological science and technology have developed rapidly. By the beginning of the 21st century, the detection technology for trace amounts of blood that is invisible to the naked eye must have matured.

Japan's criminal prosecution period is 15 years, and this bastard will never escape the punishment of the law.

It's just... that will keep the murderer at large for a long time.

Justice delayed may hardly be justice.

Therefore, Lin Xinyi simply didn't care whether these technologies were mature or not, he just put on a face of "you're dead" and said to the young man in a cold tone:

"Idiot, is this kind of insight still alive?!"

"You probably don't know at all-"

"As long as the forensic doctor removes the blood-stained skin that shows blue light on your body, puts it into a beaker, increases the digestion solution for incubation, and then extracts and washes it through the column... Then you can use the purification column to repeatedly pump the digestive solution of the large system through the column. extraction, allowing the limited DNA in the digestion solution to concentrate on the column membrane in the process.”

"Finally, a small volume of pure water is added to elute, and high-quality and high-concentration DNA can be obtained."

In order to enhance persuasion, Lin Xinyi simply explained the detailed operation process again:

"At that time, the police will naturally find out who the blood on your body belongs to."

"And if the blood found on your hands is that of the dead..."

"Oh, do you think you still have room for sophistry?"

"me…"

The young man's face was extremely pale.

He has indeed never heard of any science and technology that can detect occult blood DNA, and he doesn't know if this kind of science and technology really exists.

However, when I heard Lin Xinyi speak in such a long-winded manner, he was very professional...

Without culture, he can only believe.

Thinking of this, the guy unknowingly broke out in a cold sweat.

As he tensely tightened his body, he involuntarily stepped back.

"You still want to run away?"

Lin Xinyi frowned slightly.

Miss Maurilan clenched her fists, causing a crisp sound.

"I…"

The young man's eyes were full of unwillingness.

But when he recalled the smashed wall at the entrance of the stairs, he still stopped with a livid face:

"I plead guilty."

Chapter 46