Entries in chemistry (4)

Friday
Oct072016

Nobel Price for molecular machines

On Wednesday this week, the Nobel Prize in Chemistry 2016 was awarded to Jean-Pierre Sauvage, Sir J. Fraser Stoddart, and Bernard L. Feringa for the design and production of molecular machines. What are molecular machines? These tiny machines are a thousand times thinner than a strand of hair and made of linked molecules with movable parts. 

Since the mid 20th century, chemists have been attempting to produce molecular chains in which ring-shaped molecules were linked together. Normally, covalent bonds hold the atoms in molecules together. In these chains, chemists wanted to create mechanical bonds, where molecules were interlocked without directly interacting with each other. In 1983, Jean-Pierre Sauvage used a copper ion to create molecular chains with a yield of 42%. These molecular chains, called catanenes, were early type of non-biological molecular machine. In 1994, Jean-Pierre Sauvage’s group succeeded in producing a catenane in which one ring rotated around the other ring when energy was added.

The second major step was completed by Fraser Stoddart in 1991, when he developed a rotaxane, in which a molecular ring was threaded onto a thin molecular axle. An electron-poor ring was threaded around an electron-rich axle. The addition of heat could be used to control the movement of the ring along the axle. Molecular lifts, artificial muscle and a molecule-based computer chip have since been created using rotaxanes.

Bernard Feringa was the fist person to develop a molecular motor in 1999. The motor consists of two flat chemical structures joined by a double bond between two carbon atoms. Methyl groups attached to each rotor blade function as ratchets that keep the molecule to keep rotating in the same direction. Exposure to UV light pulses cause the rotor blades to move 180 degrees around the central double bond. His group has optimized the motor so that it now spins at 12 million revolutions per second. Using molecular motors, he has rotated a glass cylinder that is 10,000 times bigger than the motor and also designed a nanocar.

The Laureates have started a toolbox of chemical structures that can be used to build increasingly advanced creations, such as a molecular robot that can grasp and connect amino acids and intricate webs of molecular motors that wind long polymers.

In the 1830s, when the electric motor was at the same stage, scientists could display various spinning cranks and wheels, but had no idea that the electric motor could like to instruments like washing machines, fans, and food processors. It’s interesting to imagine what the future could hold for molecular machines!

-CW

Friday
Jun212013

First Summer Subgroup Meeting

This week, we summer students had our first, full subgroup meeting with Jacob, and, while it was a little intimidating at first, it was such a great learning experience that I really enjoyed it. Since this was the first time we exposed to each other’s projects, we spent a good portion of our time explaining the background behind them. I volunteered to go first, and through Jacob’s questioning throughout the whole meeting, I learned three major things:

  1. I thought I knew the fundamentals of the technology with which I am working (fMRI, MR-PET, baseline and blocking scans, etc), but during my short presentation, I realized that there were certainly some holes in my understanding, and fortunately they were quickly filled in that time. Even after reading some papers and plenty of Wikipedia articles, at the beginning of the summer, my understanding of all of this was quite hazy, but as I keep gathering these points of understanding and insight, the picture is becoming clearer and clearer. That understanding is making me really appreciate the technology I’m working with, and as everything starts to clear, I feel like I’m developing a stronger sense of ownership over my projects, which is exciting.
  2. I’m beginning to work on my skills at explaining what I do in science in layman’s terms. Jacob urged us to start our talks with something wicked big picture—in his words: “one step below ‘the brain is important’”—and we all struggled with it. I think that is because most of the time when we talk about our work in science, we’re in the academic setting where everything is either currently studying something in the sciences or they’ve somewhat recently seen the basics in high school. Honestly, coming into the meeting, I thought my skills in this department were decent, as I’ve done a fair amount of tutoring both formally and just with my friends/classmates, and in those sessions I could break down concepts into simpler terms. However, once again, they had a general exposure to the material to begin with, so I really wasn’t testing my skills fully. As someone who hopes to be a physician, especially a pediatric physician, the ability to describe physiological concepts to patients who could have little to no science background knowledge is absolutely crucial. Patients will want to know what’s going on in their bodies (and/or their children’s bodies), so doctors need to be able to tell them in a way that they’ll understand.  By the end of the summer, I want to get better at this.
  3. Okay, confession—and this might be blasphemy considering I’m working in a heavily chemistry-focused research group: I did not like taking organic chemistry this past year. I struggled through that class. Hard. I was given several packages of notecards worth of reactions and mechanisms to memorize over the course of two semesters, and I had to somehow memorize them and translate them into use when given a synthesis or product prediction problem. My bridge between that input and output was shoddy at best because I was probably missing some fundamental bits of understanding. The result? A pretty miserable two semesters and some hard feelings between orgo and me. However, when we were going through some of the reactions that my fellow interns were running, I was able to both see a real application for those piles of notecards, and I think I started to learn organic chemistry—and really learn it this time. The result this time? It was actually pretty fun! Even though I am not doing a lot of chemistry (in terms of running reactions, NMRs, TLCs, etc) myself this summer, I am excited about keeping up with what my fellow interns are learning as they do their chemistry-focused projects.  

While subgroup meetings are typically an hour long, we occupied Jacob for about two hours this past week. To me at least, those two hours were the furthest thing from time wasted, and I’m looking forward to learning more at our next meeting next week.

-Steph Lie

Tuesday
Jun112013

Research vs. Coursework

Before I delve into my topic today, I’d like to introduce myself. My name is Jaclyn Smith and I am a junior in Biochemistry and Polymer & Color Chemistry at North Carolina State University in Raleigh, North Carolina. Needless to say, my first time in Boston was last week when I got here to start my internship with the Hooker Research Group. It is my first big-city experience, so I constantly feel a little bewildered as to where I am. Hopefully in a couple weeks I’ll know my way around Boston pretty well. I am still deciding my future plans after I finish my undergraduate degree, but am thinking about graduate school or medical school. I have it on good authority that Jacob is an excellent resource to help figure these things out. I'll keep you posted on how it goes.

For my project in the lab, I am working on synthesizing a potential PET imaging agent with Genevieve, who is a Post Doc here in the Hooker Research Group. This is my first true research experience, as most of my previous experience was gained in class based laboratories. Most of these are one-or-two credit hour courses with protocols already written out and ready to follow. However, those procedures are for learning and confirming principles. One of my professors eloquently called them, “not real experiments, but exercises,” meaning that there was a correct answer to be discovered while mastering a technique. For example, an exercise may be performed for the experience of using a pipet or seeing how a standard curve is made and used. It is quite useful to learn the basics and to illustrate concepts in a controlled, laboratory setting.

Research, on the other hand, is a quest to discover something in uncharted territory. Using literature as a guide, scientists develop an idea of what they want to achieve and use trial-and-error, intuition, and some luck to make it happen. There are no ‘protocols,’ but past experience is used to develop a plan of what the next steps may be. I jumped in on a project and am just learning the ropes, but Genevieve is guiding me through the process. With her help, I performed a reaction with an 85% yield and set up another reaction more independently today. It felt really good when I took my first NMR ever and confirmed I had the product. Genevieve has an obvious intuition for the chemistry of a reaction and can eloquently explain it but she usually has me explain it to her, ensuring my understanding of the experiment.

While I have enjoyed my lab-based classes in the past, I am finding the creativity involved in research quite appealing. The summer is just beginning, and I feel as though I have learned a ton about research already. It will be interesting to see what will happen in the next few weeks as I get more experience and have more chances to try reactions on my own.

Jaclyn

Friday
Jun072013

One Summer Intern's First Week Experience!

I've never done a blog post before so I'll start with introducing myself. My name is William Taylor and I am a senior Biology major with a minor in Chemistry at Jackson State University in Jackson, MS. I am excited to be here in Boston working with the Hooker Research Group. When I first arrived to the lab I was rushed with feelings of nervousness and anxiousness that comes with any new experience. However, once I began meeting everyone in the lab all of those feelings quickly vanished. Coming from the "Hospitality State" I expected everyone in Boston to be mean and rude, which is a common stereotype of people up north where I come from. However, this was not the case. Everyone in the lab was extremely friendly and welcomed me with open arms. This made me feel welcome and I knew that my experience here would be a positive one. The first day was a little rough because there was a lot of new information thrown at me all at once, which was mentally overwhelming at times, but I learned a lot and was excited to start on my project. I work with Emily and she's an awesome person and an even more awesome teacher that really makes me think outside of the box about everything we do in the lab. She's teaching me how to think like a true independent scientist and I love it.

Since I have only been here for one week I have not gotten to see much of Boston, but I am excited to get out and explore all that it has to offer. I am living in Jamaica Plain for the summer and I love the area and the culture there. Overall, I'm excited to be here, and I will be sure to keep everyone updated on my progress and experiences here this summer.