week4

The design of the fluorescence array sensor is made like the picture shown below. There are nine different sensor arrays. The material used in the chip is PDMS.

And the results of each ion being tested were predicted by reading the relevant reports, such as the picture below shows how the sensor array would become when there is only Mg²⁺.

We had made the predicted results of five different ions in the waste water. However, this means that we may find only one ion in the water by each sensor from the result. Because we did not take any experiments, it became tough to predict how each sensor array would change when several ions are estimated.

In the next week, the post is to be made, as well as the brief report. And for further research, the information about how to analysis the changed colour of each sensor array is to be found, in order to make a more specific results. For example, we may connect the sensor array to some machine which can analysis the comments of a colour. And according to those changes, we could find out which ions are contained in the waste water by comparing with the predicted results.

week 3

This week, we are still reading the relevant reports and papers to obtain more details about the design. More recognition moiety which is different chemical source that can identify the target mental ions in the sewage, such as, Ca, Mg, Hg, Cd, Co. meanwhile, the details about the respond of each sensor unit to different ions are also measured. There will be several fluorescent reagents for one mental ion, which means if the first reagent is not able to detect the target ion, the other reagents of the same class will continue to do the same job, and these reagents are increasingly sensitive. Hence, the rough measurement of the concentration of the target ion is obtained.

At the same time, the basic structure of the design, which is based on the microfluid technology, has been sketched on the paper.

The details of the structure of the design are not figured out, for instance, the width of the channel, how to pull the sample water and the reagents into the reactive cell, furthermore, how much reagents should be used in the reaction.

The statistics of the results shown by the fluorescent reagents have not been considered. At the same time, the transform of the results from chemical signals to the processible data are not considered neither.

week 2

This week more information about micro fluid was read as the technology of micro fluid is an important part of this project. Mainly the aim was found and the plans were set. It was understood that this sensor is supposed to have several recognition moiety to identify the metal ions in the wasted water. According to the different chemical reactions due to some ions being tested, it can be observed by machine or other ways. The different colour combination can represent which ions are in the water.

During this week, the target is more clear, and we had found the basic prototype of a fluorescence sensor by using the technology of micro fluid.

The most common unit of the Micro-fluidic chip is the T-sensor or Y-sensor, which is shown below.

Sample liquid (1) and reagent solution (2) are pushed into the main channel from the injection port respectively. Due to the macromolecule and the particles diffuse quickly and micromolecule diffuse slowly, ions, which are micromolecules diffused into the reagent quickly and have reaction in the interdiffusion region.

As it is known now that the array sensor can show different colour combinations to indicate different ions in the tested water. However this may test only one ion and cannot show if there are several other ions. This means that we have to find out or hypothesis what the result would be if there are other ions.

Because the micro fluid would not move itself, there has to be some other ways to make the fluid move. Currently, we may use the capillary effect or use pressure to pump the water into the sensor.

The 1st Week---No idea of what exactly doing

The two paper works were finished reading, and some information about fluorescence sensor were searched. It was believed that the fluorescence sensor array is made of a group of fluorescence sensors to better estimate the components in the air or inside some other things, like to monitor the surrounding environment. There are generally three parts to form a fluorescence sensor, the acceptor to fetch the target; and the linker to feed back the signal and connect the acceptor with the fluorophore; while the fluorophore part is to show if the target is detected by the acceptor.

The sensor array is made up of lots of sensor units. In the array, each sensor unit has different reactive to different materials. At the same time, each material causes different reactive of different sensor units.

The flourenscence sensor, according to the web information should be like the picture below.

There were challenges we had encountered this week, while looking for the information about the fluorescence sensor, it was found that fluorescence sensor is mostly used to estimate temperature, not in the area of chemistry or biology.  We have no idea about how to start the project, which kind of florescent sensor array should we choose and what field the sensor array should be used in.