Microfluidics Application: Cell Sorting
Cell sorting consists on separating cell according to their properties.
These properties are of different types, such as intracellular (inside the cell) or extracellular (outside the cell).
The properties worked in this type of separations include DNA, RNA, protein molecule, morphology, size or shape.
Furthermore, there are some different types of cell sorting.
There are two main types when cell sorting. As said before, these techniques, that are called flow cytometry and magnetic bead separation, are used to separate cells into different population.
The biggest difference between these two methods is that flow cytometry sorts cells one by one, while magnetic bead separation works on all cells at once. Although both methods are efficient, it is better to know their relative strenths and weaknesses to choose among them.
The importance of cell sorting:
As known, cells are basic structural and functional unit of all living organism, that is why the ability to isolate and sort different cell types within organs and tissues has led to many established principles in medicine and physiology.
On one hand, and taking into account the research field, the ability to separate cells into distinct populations enables the study of individual cell types isolated form the heterogeneous population without contamination from other cell types. This technology enables research in areas as varied as regenerative medicine, cancer therapy and HIV pathogenesis.
Moreover, in terms of clinical usage, it is possible to introduce the enriched cell populations to a patient who has a clinical need for those cells, and it also enables the enumeration of cells within an individual’s blood system ad can help on the repopulation of the immune system.
Molecularly Imprinted Polymer – MIPs and Microfluidics
As mentioned before, using MIPs have several advantages, but if MIPs and microfluidics are worked together, they have even more positive points.
To start with, the materials used in microfluidic platforms are more or less inert, transparent and, moreover, they are not toxic.
This allows to work with all kinds of analytical techniques.
In addition, valves can be implemented in the microfluidic device, and this action allows the directed flows into certain areas of the chip.
Furthermore, the main advantage of inserting MIPs into microfluidic devices is that minuscule channels reduce diffusion form a solution to the imprinted surface.
This reduction brings a significant reduction of response timers for sensors or an increase of throughput for separations.
MIPs Applications and Microfluidics
The main applications of MIP’s are in the area of sensors and separation.
Moreover, as MIPs are fast and cost-effective, it is mostly used in the fields of chemistry, biology and engineering.
Due to the specific binding site created in a MIP this technique is showing promise in analytical chemistry as a useful method for solid phase extraction.
According to the effectiveness of the MIPs and as it is a cheaper and easier production of antibody/enzymes, it is nowadays used in the medical research and application, applications such as Controlled release drugs, drug monitoring devices and mimetic biological receptor .
Speaking about the advantages of MIP’s, they offer many advantages over protein binding sites. Proteins are difficult and expensive to purify, denature and are difficult to immobilize for reuse.
Synthetic polymers are cheap, easy to synthesize, and allow the elaboration of synthetic side chains to be incorporated.
Microfluidic Application: Molecularly Imprinted Polymer – MIPs
In a Molecular imprinting process, functional monomers are selected to allow self-assemble around a template molecule and subsequently polymerized in the presence of a cross linker.
Together with it, molecularly imprinted polymer (MIP) is a polymer that has a «memory» of the shape and the functional groups of a template molecule.
The aim of this material is to recognize selectively the template molecule used in the imprinting process, and to act as an antibody. High molecular recognition properties can be achieved with these MIPs for a variety of molecules.
Saying it in a simpler way, Molecular imprinting is making an artificial tiny lock for a specific molecule that serves as miniature key. In addition, there are two main ways and methods for creating these molecularly imprinted Polymers:
This method is a powerful technique to create nano-structures using predesigned compositions. It is based on the combination of compound molecules by different forces. Moreover, it allows the molecular interactions to form the cross-linked polymer
2. Covalently linking:
This second method which is used, as well as the first method, for the MIP’s formation, involves covalently linking the imprint molecule and the monomer. Once the polymerization is done, the monomer is separated from the template molecule.
Microfluidics for Neuron Devices
Offering a wide selection of neuron device product arrays, our products allow axons and dendrites to be fluidically isolated from cell bodies.
The neuron devices provide compartmentalization, fluidic isolation and improved cellular organization over traditionally chaotic neuronal cell cultures.
Are you thinking about working on microfluidics from the Neuroscience field? Do you need any help in any step of the process?
Different types of products:
A. Products suitable for cultures which do not grow long processes.
B. Tools that can separate cell bodies from axons
C. Platforms for long term experiments ensuring axonal isolation
D. Culture neurons and other combinations of cells
E. Perfusion chips
Microfluidic Application: Cell Culture
Cell culture studies based on Microfluidics are said to provide a valuable complement to in vivo experiments, because it allows a more controlled manipulation of cellular functions and processes.
Even if obtaining a pure population of primary cells can be a difficult and hard process, it gives many advantages to work with it, such as;
1. Flexibility when designing the device, it gives the opportunity to adapt to the client’s needs.
2. It gives experimental flexibility & control, which means that is possible to control and make different experiments while creating.
3. Moreover, a low number of cells are needed, because microfluidic cell culture devices reduce the cell population to a few hundred cell, or sometimes, even to individual cells. This increases the spatial and temporal resolution for the experiment.
4. Single cell handling and Real-time on chip analysis: This point is related to the previous, one, because microfluidic cell culture includes the ability to more closely mimic a cell’s natural microenvironment, working directly on chip , and moreover, working in real time.
5. Microfluidic cell culture devices also make it possible and reliable to study complex cellular behaviour, such as the relationship between single cell movements and collective cell migration.
6. Related to the real time on chip analysis, this system gives the opportunity and advantages of precise control of experimental conditions.
7. Moreover, microfluidic cell culture is able to incorporate analytical biosensors into the culture platform.
Microfluidics Application: Cell Culture
CELL CULTURE : As known, a single cell is what builds the human life, and the genetic material of all those cells in the human body hold the secret to inherited diseases, such as cystic fibrosis, Alzheimer or other complex diseases.
Taking this into account, Cell cultures and DNA can be established from blood or small fragments of tissue (biopsies).
In its simplest form of cell culture, it involves the dispersal of cells in an artificial environment composed of nutrient solutions, a suitable surface to support the growth of cells, and ideal conditions of temperature, humidity, and gaseous atmosphere. These systems are needed for aa researcher to measure the response of the cell’s alterations in culture, prospective drugs, the presence or absence of other kind of cells and viruses precisely.
Cell culture, what for?
The mass culture of animal cell lines is fundamental to the manufacture of viral vaccines and many biotechnology products. And the use of cell culture has clear advantages, such us:
Microfluidics Application: Biomarker for Detection through Microfluidic Chips
Biomarkers are the physiological,biochemical or morphological changes that occur as a result of exposure,generally, to a toxic substance. The Biomarkers are only the measures/responses at molecular and cellular level because it is the perfect situation to study the cause-effect relationships and mechanisms of action of these substances.
It is important to understand their mechanisms of action to develop medical or detection devices. Other features that allow its use is the reproducibility, sensitivity, specificity and especially they present a very fast response time for detection, among other things.
Due to these features it is an instrument widely used both in the environmental field and in the health industry.
It is essential that the biomarker response time is short , so that it can be used as “early warning system” and if also shows a diagnostic value, it can then be used predictively.
We can distinguish two types of biomarkers, biomarkers that indicate exposure and those that indicate damage from exposure.
Microfluidics Manufacturing: DRIE Process (Deep reactive ion etching)
The DRIE – Deep reactive ion etching: In this attack , a highly anisotropic(focus on one direction) etching, we can define the desired structures on silicon with the heights defined before. It is a used to create also through holes and estructures in wafers / substrates, with typically high aspect ratio.
The definition obtained with this attack over the Silicon is very good. We use the Bosch process to do it.
First we passivate with metals the wafer parts you want to keep and then do the attach with the ion plasma which removes the silicon from the non passivated parts.
To do the DRIE process , we use a special machine you can see in the photo below.
Microfluidics Manufacturing: Anodic Bonding
The Bonder enables Anodic Bonding (Sealing) between a Silicon wafer and a Crystal Wafer. This seal is used primarily for connecting silicon / glass and metal / glass through electric fields.
The requirements for anodic bonding are cleaned surfaces availability on both wafers and the atomic contact between the binding substrates through an electrostatic field should be strong enough