When He Jiahui saw the pinprick on the neck of the deceased, he had already concluded that the deceased should have been in a coma or deep sleep when the murderer killed him.

Otherwise, if he suddenly received a needle in his neck, he would definitely wake up. Moreover, as a doctor, the deceased had rich medical knowledge and would definitely go out to seek help as soon as possible. He would not be able to stay where he was and wait to die.

There were no signs of struggle or struggle at the scene, and no injuries were found on the head of the deceased, which confirmed that the deceased was not knocked unconscious.

So He Jiahui thought of sleeping pills.

Sleeping pills often contain a certain amount of sedatives, which are physiological hypnosis. In this state, even if a needle is inserted into the neck, the person will not wake up.

At He Jiahui's reminder, forensics gave priority to testing the water cups, beverage bottles and food packaging collected at the scene.

Soon, the forensics also sent the detection information to Huang Qifa.

"We found two disposable coffee cups from Starbucks in the trash can in the tea room. In one of the cups, we found a reaction with imidazopyridine. After further testing, it was found to be zolpidem.

Saliva was collected from the rim of the coffee cup and DNA comparison is being carried out. However, the fingerprints of the deceased Liu Guoqiang were also found on the coffee cup. It is basically certain that Liu Guoqiang drank this cup of coffee." Huang Qifai answered.

"Zolpidem? A third-generation sleeping pill! No wonder it can't be detected in the blood. The half-life of zolpidem in the blood is only more than two hours, and its metabolism is very fast, so it can't be detected in the blood of the deceased.

.”

He Jiahui paused and then introduced: "After a person dies, metabolism will not stop immediately, but will continue for a period of time. Metabolism will not completely stop until the cold corpse occurs.

Although zolpidem is no longer detectable in the blood of the deceased, zolpidem is metabolized through the kidneys. If the kidneys of the deceased are examined during the autopsy, it should still be detectable."

…

As early as the beginning of the 20th century, scientists discovered that barbiturates have a sedative effect, and then successively synthesized other sedatives, which were also the first generation of sleeping pills.

However, the effect of the first generation sleeping pills is relatively poor. A moderate dose is required to improve sleep. Moreover, it also has a great impact on other drugs. It can easily affect people's breathing and have adverse reactions on the central system.

.

The second-generation sleeping pills are mainly benzodiazepine sedatives, which are also the most frequently used sleeping pills in clinical practice. The diazepam that ordinary people usually take falls into this category of drugs.

This type of drug has a high therapeutic index, low toxicity to internal organs, and is relatively safe. However, the disadvantage is that the half-life is relatively long. It can induce sleep after taking the drug, but it is easy to cause insomnia and anxiety after waking up.

You read that right, taking sleeping pills will cause insomnia as a side effect, so many people will take sleeping pills and their insomnia will worsen.

Moreover, this type of sleeping pills can only be dissolved in water in very small amounts. If the murderer intends to use this kind of medicine to drug people, it will be obvious at a glance when he puts it in the water. There will be some white solids floating in the water. It will take a lot of eyes.

Only bad people can drink it!

However, this type of medicine can be dissolved in alcohol, so there is no problem if it is mixed with wine. Especially foreign wine, which has a color, it is almost invisible when sleeping pills are mixed in.

However, doctors are not allowed to drink alcohol during working hours, so the murderer could not have used second-generation sleeping pills when he gave the deceased sleeping pills.

The third generation of sleeping pills did not come on the market until the 1980s. This generation of sleeping pills is very effective when taken orally and can reach its peak concentration in the blood half an hour after taking it.

Moreover, the safety of the third generation sleeping pills is relatively high, and it is not easy to produce tolerance and dependence. As long as there are no allergies, there are basically no side effects.

Take the more common zolpidem as an example. Its half-life in the blood is only more than two hours, and it is only metabolized by the kidneys. After taking the medicine and sleeping for a while, it will be gone in the urine, so naturally it is not easily absorbed.

detected.

This is not like the second generation sleeping pills, which are also metabolized through body fluids and milk. If a nursing mother takes sleeping pills and breastfeeds her child, the baby will sleep with her.

Although the half-life of zolpidem in the body is only more than two hours, it will soon become undetectable. However, zolpidem mixed in drinks does not have a half-life, so forensics can detect zolpidem in a coffee cup.

Residue.

Huang Qifai also started thinking at this time, and he said: "The deceased came to work the night shift, and he would definitely not take sleeping pills on his own initiative. In this case, the murderer should have put sleeping pills in the deceased's coffee.

After the drug took effect, the deceased felt a little sleepy, so he went to the lounge to rest. The murderer waited until the deceased fell asleep, then entered the lounge and injected an overdose of sedatives into the deceased, causing his death.

We have one more clue, as long as we find out who drugged the deceased’s coffee cup, that person will definitely be the murderer!”

He Jiahui asked: "Besides the fingerprints of the deceased, are there other people's fingerprints on the coffee cup?"

Huang Qifai understood instantly: "You are right. When the murderer took sleeping pills, his hand would definitely come into contact with the coffee cup, leaving fingerprints! I will ask for forensic evidence immediately."

Huang Qifai said and sent a message to Forensic, and after a while, Forensic replied with the results.

"Forensic evidence said that there was only one fingerprint of the deceased on the coffee cup. It seems that when the murderer administered the sleeping pills, he either wore gloves or deliberately wiped off the fingerprints on the coffee cup." Huang Qifai said with some frustration.

He Jiahui pondered for a moment and then said: "You just said that the forensics found two disposable Starbucks cups in the trash can in the tea room.

Normal people would not drink two cups of coffee at one go, so it means there are two people drinking coffee. If the two cups of coffee are bought at the same time, we may be able to find new clues about the murderer from the other coffee cup."

"Then how do you confirm that two cups of coffee were bought together? There are more than 200 Starbucks coffee shops in Xiangjiang, and there are several within five kilometers of this hospital alone. Before the doctor comes to work, it is also OK to buy a cup of coffee.

It's normal." Huang Qifai said.

"Sir Huang, how long has it been since you bought your own coffee?" He Jiahui smiled slightly and then said: "When you go to buy coffee, there will be a label on the coffee cup, which will have the type of coffee you bought, such as

Americano, latte, etc., in addition, there will also be a number. If two cups of coffee are ordered together, the numbers will also be connected together."

"It's so simple, why didn't I think of it!" Huang Qifa nodded suddenly, and then said: "I'll ask the forensic doctor right away."

Huang Qifa sent a message to the forensic doctor, who immediately sent a reply.

"You guessed it right, the labels on the two coffee cups are indeed consecutive numbers, which means that the two cups of coffee were bought together." Huang Qifai said.

"Are there fingerprints on the other coffee cup?" He Jiahui asked again.

Huang Qifa sent another message to the forensic doctor and asked the forensic doctor to do the test. After a while, the forensic doctor replied to the message.

"After comparison, Deng Qiaomei's fingerprints were found on another coffee cup." Huang Qifai showed joy on his face and continued:

"The murderer was indeed her! She should have bought coffee for the deceased, and then put sleeping pills in the coffee. After the deceased fell asleep in the lounge, she went to kill the deceased!

Deng Qiaomei had the motive to commit the crime, and now we have found the important evidence of the coffee cup, so we can now detain her."

However, He Jiahui frowned. He did not agree because he felt that there were still many doubts. However, He Jiahui did not stop Huang Qifai. After all, apart from Deng Qiaomei, no other clues could be found at this stage.

Huang Qifai immediately ordered a search of Deng Qiaomei's personal belongings. At the same time, he took several other people to arrest Deng Qiaomei.

…

In a certain lounge, doctor Cai Shude and two nurses Zhou Yuting and Deng Qiaomei were all staying here.

The three people did not sit together, but sat apart from each other, and they were all separated by a distance. At the same time, the three people looked at each other warily.

The three of them were obviously suspicious of each other, but due to the favor of their colleagues, they managed to maintain an even balance.

They all knew that the murderer of Dr. Liu was among the three.

When you stay in the same room with a murderer, you naturally have to be very cautious.

The door opened, and Huang Qifa walked in with a group of policemen. He came directly to Deng Qiaomei and said:

"Ms. Deng, we now suspect that you are related to a murder case, and we need to take you back to the police station to cooperate with the investigation. You can remain silent, but what you say will become evidence in court."

"Me? Why me? Sir, are you mistaken? You are arresting people randomly!" Deng Qiaomei suddenly looked surprised.

Deng Qiaomei showed an extremely uncooperative mood, so Huang Qifai had no choice but to ask: "Ms. Deng, did you buy a cup of Starbucks coffee for Dr. Liu Guoqiang last night?"

"Yes, isn't it normal to drink a cup of coffee to refresh yourself while working the night shift? What's the problem with this!" Deng Qiaomei said.

"Refreshing?" Huang Qifai sneered: "But we found zolpidem in the cup of coffee Dr. Liu Guoqiang drank, which is the main ingredient of sleeping pills. Ms. Deng, how do you explain this?"

"Sleeping pills? Why are there sleeping pills in the coffee?" Deng Qiaomei looked surprised.

"Ms. Deng, the police are asking you now, not you!" Huang Qifai continued: "Dr. Liu is here to work the night shift, not to sleep. It is impossible for him to give himself sleeping pills, right?

And you bought Dr. Liu’s coffee, why is there sleeping pills in it? Shouldn’t this question be answered by you?”

"How do I know?" Deng Qiaomei replied instinctively.

"That's because you wanted to kill Dr. Liu, so you drugged his coffee. After he fell asleep, you secretly went to the lounge and injected an overdose of sedatives into his body, killing him.

"Huh?" Huang Qifai asked forcefully.

"No, I didn't kill anyone! How could I kill him! He and I are..." Deng Qiaomei suddenly stopped talking.

Huang Qifai said, "Ms. Deng, you want to say that you and Dr. Liu have an improper relationship between a man and a woman! Our police have long known this!"

And we also know that Dr. Liu plans to marry his girlfriend, so he wants to end his relationship with you. I guess this is your motive for killing!

You finally found a golden husband like Dr. Liu, but Dr. Liu planned to leave you and marry another woman, so you killed him in anger, right?"

"That's not the case. I have feelings for him, and I do resent him for marrying another woman, but I didn't kill anyone!" Deng Qiaomei quickly shook her head in denial.

At this time, a subordinate walked in and whispered a few words in Huang Qifai's ear.

Huang Qifa suddenly beamed with joy, and he ordered: "Send it to the forensic department for testing immediately!"

Huang Qifai then turned to Deng Qiaomei and said: "Ms. Deng, you said you did not kill Dr. Liu, but we found a used syringe in your closet in the dressing room.

This syringe has now been submitted to forensic testing. I guess the ingredients of a tranquilizer should be found in it, right? You used this syringe to inject an overdose of a tranquilizer into the deceased, causing his death!"

"Syringe? What syringe?" Deng Qiaomei looked confused.

"At this point, are you still denying it? It doesn't matter, I can wait. Our forensics is very efficient. It won't take long for the test report to be sent. Then you will be willing to follow us back to the police station.

Huang Qiqi said confidently.

The forensic efficiency was indeed very fast. It didn't take long for the test results to be sent to Huang Qifa's mobile phone.

"Forensic evidence found midazine, promethazine, and chlorpromazine in the syringe, which are exactly the same as the overdose of sedatives found in the deceased's body. In other words, this syringe is the murder weapon!"

Huang Qifai smiled triumphantly and continued: "There was sleeping pills in the coffee you gave the deceased, and the murder weapon was also found at your place. The chain of evidence is already very complete! Miss Deng, you need to hire a better lawyer.

Got it!"
To be continued...