The hardest bit so far has been trying to get 2 serial devices to synchronize within 2 milliseconds of one another. I had some success. Using 2 of the researchers pulse oximeters, and at least 7 subjects, I managed to get clean photoplethysmograms (PPG waveforms)!

Over the course of the week, I also managed to synchronize 2 Pulse Sensor Amped and get at least 2 clean waveforms with the promise of more and I also synchronized one CMS D50+ pulse ox and one Pulse Sensor Amped pulse sensor and get a few clean waveforms.

These data are meant to help my fellow teacher researchers in answering their questions more so than mine, but it is nice to be helpful.

Best timing results for all systems (once synchronized by hand) was time resolution of ±3 m/s. This is enough to characterize a single waveform and even to find the pulse transit time.

Week 3 – The Week of Redemption

We are finally bearing the fruits of our labor.  Our week began a bit shaky but, in the end, we finally have data.  The Instrument Gods blessed us with several days of remarkable work.

This week we continued our quest in trying to conceive a method for detecting nano-TiO2 in water.  Our foundation is based on finding an organic chelate (molecular magnet) that will latch onto nano-TiO2 and keep it in suspension in order to examine the water sample in a UV-Vis Spectrometer.  The chelate and the nano-TiO2 form a coordination complex. The close coordination between the two molecules allows for a charge to transfer back and forth from the chelate to the TiO2 and back when excited by light (electrons). This transfer results in a fluorescence signal that we will use to detect TiO2 in water.  This measurement will be key to detecting nano-TiO2 in different types of water samples.

We finally have found promise in one of the 40 chelates we have tested.  2,3-Dimercaptosuccinic acid (DMSA) has proven its weight in Titanium.  It has kept nano-TiO2 in suspension.  Has produced significant zeta potential numbers.

The zeta potential is the electric charge between the chelate-nanoparticle complex and the solution it is in (for now we are using DI Water).  The higher the zeta potential, especially in the range of +/- 30-40mV, then signifies the chelate-nanoparticle complex will remain in suspension.  This will then allow us to possibly attain a measurement via the UV-Vis Spectrometer, which will be the center for further studies.

So relieved that we were able to move forward and get a step closer to our final goal.  Let’s see what this week has in store!!!!  Happy Fourth of July everyone.

I feel like I am getting the hang of being in the lab. I have been able to do almost everything on my own with my mentors close guidance. This week we were able to make the membranes with varying concentrations of PVDF and PVP.

Monday- We were trained on how to use the Yflow Electirospinner in the BRC here at Rice.This is a fancy machine that automates many of the variables of electrospinning.

It also gives us the  option to use special needles attached to our syringes. This will allow us to spin 2 solutions at a time and create a inner core and outer covering with different pore sizes.

Tuesday-I was able to go through the process of sputtering ( spraying a thin layer of gold) on our electrospun membrane and using the Scanning Electron Microscope (SEM).

Wednesday- I had some awesome visitors come by and I was able to show them my work space. Then, I was able to mix our first polymer solution and we brought it over to the BRC later in the afternoon and created our first membrane.

Thursday- We were able to get a glimpse of projects being completed in the nanotechnology RET program. Their projects all deal with nanotechnology, but not water treatment. I was able to see a lot bioengineering applications of nanotechnology. Later, I was able to electrospin our second membrane. My mentor, Seth, spun the fourth membrane.

Friday- We mixed our last solution and spun our last membrane. We will compare the surface structures of each by using the SEM next week.

This week I have also had a lot of time to think about my lesson. As I  wrote my script and continued to think about what we are trying to achieve in the lab, I thought about how I could have my students model our approach.

Originally, I wanted my students to discover the hydrophobicity of different items (metal, wood, cardboard, and plant leaf)  by observing the contact angle of a drop of water and then measuring the tilt angle at which a drop of water would roll of the material. I would then allow them to choose different items to modify their surfaces such as petroleum jelly, oils, detergents, “magic sand”. Then I would dirty  (apply salt or pepper) to their surfaces. Then we would test their designs by pouring water over them to see who’s surface is the cleanest.

After learning more about our porous membranes, I believe I could also have the students create a macro scale version of the nano scale membrane. I am thinking I would give them each a flat piece of cardboard. This would be their membrane and they can modify the surface by cutting holes, adding bumps. The water could be modeled by marbles or small balls. They could then measure the number of pores, size of pores they created, and the tilt angle.

What do you guys think? Do you have any cell membrane, pore size, hydrophobic/hydrophilic labs that you currently do?

This week I sulfidized a lot of coupons, I digested coupons, I brainstormed protocols, and I presented preliminary data.

Oh, I just realized I need to make a comment about the previous sentence.  A long time ago, before I was a teacher, I worked in a factory that made circuit boards.  We made huge 3’x2′ sheets with lots of layers and lots of individual small circuit boards to cut out later.  To prove the boards were good, we cut out small rectangles from the sheet, next to the circuit boards, to check the inside layers.  Everyone called those cutouts coupons.  I guess the sheet did look like a newspaper spread with holes where someone cut out coupons.  So when we have a membrane and I cut out a piece to analyze, I call it a coupon.  And “digesting coupons” means dissolving them, or at least dissolving everything except the plastic backing.  So let me start again.

This week I sulfidized a lot of 1″ circular cutouts from membranes, I digested said cutouts, I brainstormed protocols, and I presented preliminary data.

The first thing I discovered is that my quest for efficiency produced inconsistent results.  In processing things quickly (and efficiently I might add – I would still be running coupons 1″ circular cutouts today otherwise) the process turned anaerobic (no oxygen) and produced colors different from previous work.  I also had 3x the standard deviation in silver loading.  So I am rethinking (with my mentor’s help) the protocol to produce silver membranes and sulfidized membranes.  Again for my quest for efficiency, I am building a frame this weekend to try and triple the membrane throughput.  I’ll post a picture if it works.

So I got to present my data.  It shows that partially sulfidized silver nano particles do stay in membranes longer.  Perhaps a lot longer, like months instead of weeks.  Not only was it good to present a positive outcome, I now know that even if everything else breaks down, I have data for the poster.  This photo shows the digested coupons 1″ membrane cutouts. The dark color hints that maybe even 2% nitric acid is inadequate to remove sulfidized silver nano particles.  I’ll find out this week.

Richard Daines

NEWT RET Week 3 Blog Tom Geiss

I began my week in the lab assisting Marina Marcos and Roy Arietta in preparing composite nanomaterials for an experiment to test the composite materials ability to adsorb Arsenic from a simulated fresh water sample with an Arsenic Concentration of 50 ppb. Just a reminder, the composite material is made of three different nanomaterials: graphene, iron oxide and Zinc ZIF. Last Friday, we prepared our NEWT fresh water sample using the NEWT recipe. We did everything except add the Arsenic to the NEWT fresh water solution.

Making the NEWT Fresh water can be a little challenging as some of the masses can be very small. Below is a photo of one of the salts we add to the solution as it sits on the scale. As you can see the mass (0.00072 g) is one tiny  spec of the salt.

The next step was to measure different masses of the composite nanomaterial. We measure out 10 different masses ranging from 0.000125 g to 3 grams. On two different masses we measure duplicate masses so that we can verify the validity of the test data.

After the all of the masses of the composite materials were measured we then buffered the samples with Sodium Bicarbonate. We let the different masses soak overnight. The next day we used a pH meter to record the pH and confirm they were within an acceptable range. After recording the pH we rinsed the samples in DI water. That’s when we realized we had a problem. While rinsing and decanting we saw we were losing small amounts of mass of each different sample as we were decanting. We tried to compensate by using a magnet (my idea) while decanting but we still lost material in the process. This meant that the masses we recorded at the beginning of the experiment would not be valid.

Marina and Roy being much brighter than I, quickly came up with a solution. Not a new solution of composite but a new solution to the problem.  They concluded the answer was to create additional composite material buffered in sodium bicarbonate, then create 10 new samples of composite that had been buffered and cleaned. That way the masses stay consistent throughout the experiment.

So by late Thusday or Friday we can continue our experiment with adsorption of 50 ppb of arsenic.

While were measuring our masses and preparing our samples, discussion turned to the diversity training we had attended on Monday. Mariana asked what I thought about the training. What ensued was a thoughtful discussion of how diversity is addressed in academia, business, middle school, and high school. I shared that I thought that among my peers that I teach with diversity is accepted and valued. I also thought that people still had perceptions based upon stereotypes that might be expressed in nuanced ways. Mariana shared a story about being in a food court and an acquaintance expressed surprise at her choice of food thinking she might chose a food that was more culturally relevant to her. It surprised her that someone would assume that based upon her ethnicity she only eats a certain type of food.

I have been thinking a lot about the TED talk we watched last week about “The Danger of Single Story” by Chimamanda Ngozi Adichie.  I have thought about this in a few ways. One, I think about how  I make assumptions about what types of activities they can and can’t do in a lab setting. Or how I may have preconceptions about their reading or math ability that may not be true. Even when we engage in “data mining” based upon STAR practice tests, it doesn’t tell the whole story of that student’s ability or even their real reading level. Some of my students according to the data are 8^th graders that read at the 2^nd grade level. However, when reading aloud in class they clearly have a higher comprehension of what they read, than what their test scores reveal. Reason being, they tanked the test on purpose because they did not care about the outcome.

I have also been thinking about how close minded my students are of anyone who is slightly different than they are. My students are predominantly Hispanic males between the ages of 12 and 15. They are dismissive  of anyone who does not look like them, act like them, like the same music as them, does not talk like them, does not like the same food as them, etc. etc. I know some of this is part of adolescence, but the intolerance as such a young age is depressing.

How do you get that close minded at such a young age? My stepfather was a closet racist. He worked in a culturally diverse work place. When he came home he made derogatory comments about people of different ethnic and religious backgrounds that I am sure he did not share at work. Rather than parrot these ideas, I compared his observations with the children I went to school with. I grew up in Topeka Kansas. Home if the famous Brown vs Board of Education. That Supreme Court case was decided in 1954. By 1965 when I started school, we had a diverse student population. In my observations the children of color were no different than me. We all wore pretty much the same clothes, ate the same food, listened to the same varieties of music and played and learned together with the same peaks and valleys. So I quickly decided my step father was full of it and tuned him out when he went on his racist rants at home.

So I am really discouraged that 40 plus years after I attended middle school, in some ways we have gone backwards in time. During the Diversity seminar on Monday, a participant at another location stated that they thought that social and emotional learning was key to getting students to accept and respect diversity. I totally agree. We have started using circles at our campus to address social and emotional issues and build relationships between student and staff. Success has been limited, but I am optimistic.

On Wednesday we started synthesizing started nanomaterials for adsorption tests we will start We began on Friday. The first material we created was Zinc ZIF. We are going to test the adsorption rate of the Zinc ZIF so that we have a comparison to the adsorption rate of the composite material which has all 3 nanomaterials in it.

Once we have added Arsenic to our NEWT water we will put 500 mL of contaminated NWT water in 14 jars. One jar has no nanomaterial to serve as a control and the others have various amounts of nanomaterial.

Then for three days we put the jars in a shaker that slowly moves the jars in a circular motion. This allows the nanomaterials to be moved in solution with the contaminated NEWT water.

We ran into a problem with our NEWT water. I made a bone head move and did not make a correct calculation on one of the compounds you make NEWT water with. My error in calculation, ( I forgot to divide by 1,000) which made me add 1,000 times more Sodium Phosphate than was needed for experiment.

Marina told me this happens to everyone so don’t get too upset. So we tossed the contaminated water with arsenic down the drain and started again. Just kidding. There was no arsenic in it so we didn’t contaminate the El Paso water system.

Once the NEWT water was done and we had all of our different masses of nanomaterials weighed out. We put all 27 of our samples in the shaker at set the motion at 100 rpm (see photo below). We have 13 composite samples and 13 ZIF samples and 1 control. We will take them out of the shaker on Monday afternoon and then begin to prepare them for analysis to see how much Arsenic was removed from the solutions.

That’s all for now. Next week we get into some real Rick and Morty stuff. See you then!

Lab Progress:

This week in the Halas lab, we spent most of our time analyzing date from last week’s experiment.  Analysis kits are great because they put everything into nice, easy steps.  Of course, then the kit doesn’t work the way you expect.  Here’s what happened…

First, we were able to create steam from the urea solution, but the vapor didn’t travel all the way through the condensing column.  The vapor would condense in the original flask, then drip back into the starting solution.

Second, the kit we are using is meant to test for ammonia.  It appears that urea will react with the kit as well, so we had to account for all of the background from the starting solution.

Now, with all of that said, we were able to decompose the urea into ammonia using carbon nanoparticles!  As the reaction (laser treatment) time increased, we saw more ammonia being produced.   The ammonia concentration increased in the solution and the condensed vapor!

Round Robin Tours:

Thank you so much to everyone who were kind enough to walk us through their labs on Thursday!  I got to see so many different types of research:  nanofibers being sewn into clothing, fruit flies, amino acids, hyrogels, viruses, and lab techniques that are way more advanced than I was in school!  I even got a chance to revisit my old stomping grounds before I started teaching: BRC Lab 310!

Oh, and I want to apologize for keeping everyone out in the heat.  My lab works with solar energy, so we have to be outside….

Good morning everyone!

This week in the N.EW.T. lab at ASU was about problem solving and not giving up. My research consist of determining what type of media that is impregnated with silver nanoparticles works the best at removing silver in a column. If you have been following along, I have not had much success with the media that was sent to me from Clemsen University. Although it failed most of my test so far, we were determined to make it work. I set up columns with the 2 types of Granular Activated Carbon (GAC) at .25 in. height, .5 in height, and 1 in. height to see if the media would work at all.

Finally, we had success! Both of the Clemsen GACs worked at .25 inch, and .5 inch height, but only the CU GAC #1 worked at 1 inch. Since Clemsen is trying to get publish for their new method of impregnating silver, we do not know what exactly is different from that GAC compared to the commercial GAC we are using. We will be in contact with Clemsen next week to see if we can get any more information about the GAC they created so that we can design a test that works best with that GAC.

This week I was able to spend some time in the N.E.W.T. lab that Richard is in this summer. Richard is also working with silver nanoparticles, but instead of applying them to columns to remove bromide, he is using them on filters to prevent fouling. The problem is that the silver nanoparticles don’t stay on the filter very long. To solve this, his lab is adding sulfur to the filters with silver nanoparticles to help the silver stay on longer. Richard’s role is to figure out what is the right amount of sulfur to add to the filter so that it doesn’t loose to much of its antimicrobial ability. I thought it was very interesting how they were collecting data and was able to get some ideas of how I can apply using nanoparticles in my Biotechnology classes.

Next week, I will be impregnating silver into GAC I crushed and testing it see if it works as well as the GAC they sent from Clemsen. I will also be learning how to use an ICP machine to measure the amount of bromide that is in my samples. Wish me luck!

-Taylor

P.S. Sorry for no photos this week. I am in Dallas for my students competition and the Wifi is horrible here. I will try to add some when I get back to Arizona.

This week was spent in the lab working to create a new protocol to complete a more successful separation of carbon nanotubes. I also was able to visit labs this week.

LAB VISITS

I had a wonderful time visiting labs this week. Now, I am able to better understand everyone’s research. Amazing, how everyone is working on such different projects. Sarah’s mentor did a great job of explaining their carbon nanotube lab to us. It was really cool seeing the possible applications of carbon nanotubes. Just like a fascinating look into the future.

The BRC labs were in a much more open space with collective sharing of equipment, very different than my self enclosed lab. Most members had a machine and process ready to present to us.

NEW PROTOCOL

After our weekly meeting I was assigned a new task. To work with the new molecular weights to create an aqueous two phase separation of carbon nanotubes. I was having success following the protocol correctly with the original molecular weights. Using the new molecular weights affects the two phase separation in a large way. Following my original protocol there was no phase separation of the polymers. I tried reading more papers about different molecular weights. There were only a few available and even fewer articles about two phase separation of carbon nanotubes.

My mentor pushed me to list all of the parameters that could possible affect my separation. I created a list of about 15 different variables. It’s a hard challenge to try to create a protocol and only change one thing. What makes it difficult is that you see that it didn’t work so you want to start to make bigger changes.  Later I learned that there are no protocols using these molecular weights and that it was recently uncovered. This is making the challenge even more difficult. I’m now trying to work out the new protocol.

HIGHLIGHTS

• sometimes there are no papers to help you
• think of ALL of the small parameters that can be change
• change one small thing at a time
• use not only math but also your observations
• sometimes it’s okay to go with your instincts

UTEP Newt

My first week of NEWT at UTEP was one of shock and awe.  I was shocked by how much I didn’t know about chemistry and I am in awe of the people in the group I have been assigned too. Their knowledge of inorganic chemistry and their patience with me is truly amazing.

I have been assigned to Dr. Dino Villagran at UTEP and I am working with his graduate student Mariana Marcos. I told Dr. Dino right away that I was a little concerned about my current level of understanding of chemistry. He graciously offered to let me sit in on his General Chemistry class that he is teaching at summer school. So almost every day this week my day has started at 8:00 AM with 150 other students in an auditorium. Boy have things changed since I took chemistry in college. When I took chemistry back when I was in college, there were only 40 elements on the periodic table of elements.

After chemistry class I head over to the lab. My mentor, Mariana Marcos is doing research on using nanomaterials to remove Arsenic from drinking water. The nano-materials that we will be working with and actually synthesizing are: graphene oxide (GO), magnetite (Fe₃O₄), and zeolitic imidazolate frameworks (ZIF).

Each of these three materials has shown selectivity in adsorption of arsenic in simulated drinking water. The objective of the project is to obtain and compare the adsorption capacity at 5 and 50 PPB (As) and determine the selectivity of each of the three composite nano-materials towards Arsenic.

Mariana gave me an article on removal of Arsenic from water titled: “Technologies for Arsenic Removal from Water: Current Status and Future Perspectives”, from the International Journal of Environmental Research and Public Health. The introduction of the article provided background of Arsenic as a pollutant in drinking water. Not only is Arsenic introduced to the environment via agriculture and various industrial uses, it is also introduced through natural sources such as the weathering of rocks which contain arsenic. I learned that Arsenic is a naturally occurring metalloid that that is very “mobile” in the environment based upon its parent mineral form, oxidation state, and mobilization mechanisms.

Based upon oxidation state, arsenic can exist in 4 forms. Of these 4 forms of arsenic the most prevalent forms found in water are arsenite (As (III)), and arsenate (As(V)), which are both inorganic.

Arsenic is known to be a highly toxic to all life forms and is classified as a group one carcinogenic substance by the World Health Organization.  The WHO has stated that arsenic concentrations in ground water should be limited to no higher than 10 µg/L. At levels above 50 µg/L in drinking water, people can develop a wide range of health problems including cancers. Collectively these disorders are referred to as arsenicosis. According to the article I read, the ground water contamination for arsenic is highest in Asian countries. In Bangladesh and India over 120 million people are exposed to contaminated ground water with above 50 µg/L. In Bangladesh, the arsenic level in some tube wells is as high as 4730 µg/L.

According to this article arsenic in its most common form arsenic can be difficult to remove because of its oxidation state. Typical water treatment methods for arsenic involve a two-step process for removal. First the oxidation of soluble arsenite to arsenate. After that, a removal technique must be used such as adsorption, coagulation, or ion exchange. According to the article, oxidation can be problematic as other contaminants in the water can interfere with the oxidation process.

So this is where nano-materials come in to save the day. Research has shown that iron oxide nano-materials have been five to ten times more effective in the removal of arsenic that conventional water treatment methodologies. Mainly because of their high surface-to-volume ratios. Plus, their magnetic properties make extraction from the water easier using magnets.

So this week I started in the lab helping Mariana Marcos synthesize some Fe30₄ nano-particles. You do this by a process called co-precipitation.  I don’t need to tell you guys that iron (Fe) exists in 2 oxidation states. So co-precipitation calls for using Fe³⁺ and Fe²⁺ ions in a 2 to 1 molar ratio. So a sample is prepared using 2 moles of FeCl₃ and 1 mole of FeCl_2. Then 100 ml of DI water is added. Then you heat the mixture to 85 degrees Celsius while stirring in a N₂ environment. After the temperature is reached you introduce 12 ml of NH₄OH. This reaction then yields the Fe30₄ nano-particles.

After the solution is cooled down to room temperature it is washed twice with DI water and then sonicated.

The picture below shows how the nano-particles as it looked while it was cooling to RT.

As the solution was cooling we placed a magnet at the bottom of the flask to migrate the Fe30₄ nanoparticles to the bottom. This photo shows them before sonicating.

The next picture shows the nano-particles after they have been washed twice and sonicated.

The black residue at the bottom are the Fe0₄ nanoparticles which were then dried in a vacuum over-night.

On this particular batch, Mariana reduced the volume of reactants to see if the resultant nano-particles would be less aggregated. She is looking to see if this change will result in greater surface volume. We will take samples of two different preparations and then look at images of them in a scanning electron microscope (SEM)  to see if there is an advantage to using smaller volumes of reactant.

 I can’t say enough how helpful my mentors Mariana and Dr. Dino are. They have both taken a keen interest in the lesson I am preparing and I am looking forward to collaborating with them on this project.

The Iron Throne for Nanoparticles

As I started this week’s blog, I decided a needed a better hook for the title. Last week I went with “Iron it Out” because I was working in the lab assisting in creating Iron Oxide nanoparticles. Iron oxide, iron nanoparticles, Iron it Out. Get it? Nobody said anything about my title. I got no likes on the blog, my Facebook page, my twitter, my Instagram account, not even on my Myspace page. Then I realized, I have no social media presence. No wonder! So I figured maybe I needed a better hook. So what better cultural reference than the Iron Throne from Game of Thrones. So now that I have come up with a correlation/metaphor between the nanoparticles my group is working with and the characters of Game of Thrones.

Obviously the Iron Throne would be seized by the most powerful nanoparticle in the process of removing arsenic from water. So how will the battle for the nanoparticle be won? Will there be a “Red Wedding” where one nanoparticle is deceived by others at a moment of joy only to be slaughtered? Which nanoparticle will be like Cersei Lannister? Who will be the mother of dragons? Which particle will be the John Snow nanoparticle? Will the John Snow nanoparticle become romantically involved with the Daenerys Targaryen nanoparticle  in a relationship that is denounced by all the nanoparticles except for the Jaime and Cersei nanoparticles who say “What’s the big deal?” Let’s find out.

In comparing the three nanoparticles my mentor is working with, I needed to understand how these particles are evaluated in their ability to remove arsenic from drinking water. Is one better than the others. Unfortunately, this research has yet to be done at the lab here. It was however identified by my mentor as “future work” to be done on her poster presentation of her research. So maybe that will be something I can assist with.

This spring, at UTEP Mariana Marcos and Roy Arrieta did an experiment where they tested the adsorption rates of the composite materials in adsorbing arsenic from simulated drinking water. They varied the amount of composite material with 10 different trial masses. The simulated drinking water had a concentration of 5 ppb of arsenic.

The experiment yielded adsorption data of arsenic adsorption by a composite material made of Iron Oxide, Graphene, and Zeolitic imidazolate framework (ZIF). They did not have individual arsenic adsorption data of Graphene, iron oxide or ZIF to compare. Thus my Game of Thrones analogy is not relevant regarding the ability of these three nanomaterials to absorb arsenic. Their research does indicate that the composite that used the Zinc ZIF had a higher adsorption rate that the two other composites which used a cobalt ZIF and a zinc/cobalt ZIF respectively.

The image below is a TEM image of the three nanomaterials together.  In the lower right half of the image you can see an almost transparent screen in the background. This is the graphene oxide. The darkest parts of the image are areas where all three materials are coalesced together.

Follow up from Last Week

Last week I assisted Mariana in synthesizing Iron Oxide particles by reducing the mass of the reactants from their usual recipe to create iron oxide. The purpose was to get less aggregation so that the nanoparticles could be easily characterized.  It is easier to measure the size of the nanoparticles if they are less aggregated. The image below shows the particles we created last week as seen through a TEM with a 50 nanometer scale.

Mariana is working with Dr. Ping at Rice by creating these iron oxide nanomaterials for him to use in his research in creating phages that will be conjugated with superparamagnetic nanoparticles. According to Mariana, he needs various sizes of nanoparticles of iron oxide ranging from 5 to 100 nanometers.