Manual

Cell based microplate assays

A well eyed view of what happens in each well of an Oxley Hughes microplate while it is in an Oxley Hughes inclined holder. See how the pipette tip is guided, under control, down the side of the well wall and fixes at a point away from the science. The solution always moves towards the fixing point because of the angle provided by the inclined microplate holder. All of the solution is easily removed, the microplate rotated and then fresh solution applied while resting the pipette tips on the top of the well wall guides. It’s just our way of ensuring solution exchange is both easy and simple to achieve so your science remains in place and supplies you with the best possible outcomes.

Animation of technology: Click Here

Oxley Hughes’ microplate – solution removal: Click Here

Oxley Hughes’ microplate technology applies to both manual and automated systems.

The main points are:-
– control of the pipette tip is enabled as soon as the pipette tip point is introduced to the top of the guide channel located in the well walls;

– the pipette tips are prevented from moving about and damaging the science at the bottom of the microplate wells by the modifications, incline and well guide;
– the pipette tips points have no direct or reduced contact with the science located in each microplate well base;
– the pipette tips points are positioned in the lowest part of each microplate well so all liquid flows towards to the point of pipette tip.

– and, to make solution addition so much easier and controlled, reverse the microplate in the holder, rest the end of the pipette tips on the top of the guide and you have a stable platform to easily add your next solution.

Compare what happens in an Oxley Hughes’ microplate to what happens in a standard microplate where the pipette tips regularly damage cells located on the well bottoms and residual amounts of solution remain. This leaves difficult choices to be made: harsh solution removal options or undesirably having to leave the residual solution in place resulting in ‘carry over’:

Oxley Hughes is providing an enabling technology: addressing common issues to benefit

Unlike standard microplates, Oxley Hughes’ technology enables the complete removal of solutions from the microplate wells during each stage of preparation, handling and maintenance while significantly reducing or preventing the damaged to the cells or biological material caused during the aspiration and dispensing of liquids. With standard microplates for example, microplate washing and reverse banging steps can loosen and remove cells or biological material from the surface of the microplate wells which obviously impacts on the end results and the overall assay quality.  Complete pipette tip control is very difficult or impossible to achieve with standard microplates and frustratingly, more often than desired, the pipette tips scrape the bases of the wells damaging the cells or biological in the wells. With Oxley Hughes microplates, since all or just a miniscule amount of solution is left over, there is no need to reverse Oxley Hughes microplates and ‘bang out’ the residual solutions. This means the well contents, such as cells in this example, are not subjected to this harsh handling of reversing and banging out and will therefore have the best chance of remaining in place in Oxley Hughes microplates.

There is nothing worse than preparing your cells to the required confluency and then disrupting them with a few harsh or poorly controlled handling and maintenance steps which usually results in you having to start all over again. With Oxley Hughes’ microplate technology, you will reduce the occurrence of this dramatically so you can handle and maintain your Oxley Hughes microplates with a lot more confidence, knowing full well you will have increased your chance of having more uniform science in the wells to work with after all your careful preparation work.

For example, for drug discovery in cancer research. When looking to identify a new anti-cancer drug, cells are grown in the microplate wells and the drug applied. With standard microplates, an unwanted side effect of current microplate handling and maintenance processes are the cells are easily removed so there will be the doubt that it was not the action of the anti-cancer drug that killed (removed) the cancer cells. This means lots of repeats. With Oxley Hughes’ microplates the chances of this occurring are massively reduced. Any cell death (removal) is more likely to have occurred due to the action of the drug rather than the mechanical processes used during microplate handling and maintenance.

Edge effect:

a common issue with cell based work in microplates is while you are waiting for the cells to reach the required confluency, more often than not you lose solution, especially from the outer wells, due to the effects of evaporation in a 37oC incubator. With Oxley Hughes’ microplates, since the solution exchange is controlled and gentle, you can confidently remove media solution which is exhausted and low volume and replace with fresh media solution. Using Oxley Hughes’ microplates massively reduces the chance of disrupting the growth of your cells in the microplate so you have increased your chance of having uniform cell distributions in the microplate wells.

ELISA/EIA based microplate assays

Using Oxley Hughes’ microplate technology for ELISA based assays protects the science and removes all of the solutions. This enables a full colour development as well as a faster rate of colour development to happen. More science is available to effect this and no residual wash solution is present to inhibit or impair the turnover of ELISA substrate. This improves assay outputs and reduces assay times.

Compare this to ELISA’s carried out in standard microplates. The science is damaged during the many handling and maintenance steps as well as residual wash solutions remaining in the wells for carry over. Both of these can affect the turnover of the ELISA substrate by both slowing the rate of colour development as well as the final signal. This impacts on the quality of the assay and outputs as variation in signals-to-baselines will be measured. Additionally, the assay times will be longer due to the slower rate of ELISA substrate turnover.

Fluorescence based microplate assays

Using Oxley Hughes’ microplate technology for fluorescence based assays, by protecting the science and removing all solutions, a full fluorescent signal is measured. More science is available to effect this and no residual wash solution is present to potentially impair the fluorescent signal. Also, since these types of assays are carried out in black microplates, it is often extremely difficult to determine where the pipette tip point is located in each well. Oxley Hughes technology ensures the pipette tip point always returns to the same place in each well even though you cannot see where it is in each well.

Compare this to fluorescence based assays carried out in standard microplates. The science is damaged during the many handling and maintenance steps as well as residual wash solutions remaining in the wells for carry over. Reversing the microplate and banging out the residual solution is the usual choice. All of these can affect the final fluorescence signal by reducing and varying the quantity of science available to generate the final fluorescent signal. This impacts on the quality of the assay and outputs as variation in signals-to-baselines will be measured.

Radioimmunoassay (RIA) based microplate assays

Due to the very nature of RIA’s, control of solution exchange is extremely important. Oxley Hughes’ microplate technology lends itself particularly to this as solutions can be exchanged easily and effectively in a controlled, safe method which helps minimise the risks to the operator.