Frequently Asked Questions

Before requesting a proposal from Guild BioSciences, please consider and address the following points to reduce costs, maximize protein yields, shorten turnover time, and generally streamline procedures.

Consider the Protein of Interest

• Carefully consider the method of detection for your protein of interest, as the detection procedure is often the most expensive part of the purification. For example, Western blots are commonly utilized; however, if an ELISA can be used, it is often less expensive.
• Indicate whether your protein of interest is a major or minor component of the starting material. Such information is not required, but it will expedite the process if known.
• Estimate the amount of total protein in your starting material, if possible. It does not necessarily need to be for the specific sample that you will send (although this would be ideal). It may be an estimate from a typical batch of your starting material.

Consider the Starting Material

• If possible, indicate some measure of the complexity of your starting material, such as an SDS PAGE gel stained with a general protein stain like Coomassie or silver stain. The measure may be derived from the actual sample sent or a typical sample.
• If the starting tissue will be an intact tissue or unlysed cell pellet, be able to provide the starting culture volume, the cell density of the culture before it is pelleted, and an anticipated protein yield after lysis. Also see next point.
• If GBS will conduct cell lysis/tissue disruption, provide a specific protocol for conducting the cell lysis/tissue disruption for your sample, including the specific composition of the lysis solution . (You know your starting material best; if we must develop the methods, you may accrue additional costs as we determine effective methods.)
• Describe the reagent composition of your starting material

Provide Prior Knowledge and Procedures

• Supplying any publications that provide protocols for purifying your protein of interest, or a closely related protein, is to your advantage. Sending either a PDF or a literature citation will allow GBS researchers to quickly determine how others have attempted to purify your protein and anticipate potential problems.
• Provide data from any preliminary experimentation you may have conducted. It is to your benefit to provide as much data as possible (especially regarding yield) as this will reduce the need for GBS to repeat that work to characterize the system. Reducing the time required for the initial workup will decrease the cost of your purification.

Consider Sample Transportation

• Know the appropriate federal and international regulations for shipping the material you will be sending to us and follow them. In addition, customers are required to inform us if source material contains biological toxins or potentially infectious material, and if there are any special handling requirements. For more information about shipping procedures, please visit our Links page for helpful links.
• Be aware that the federal government holds shippers directly responsible for the correct and legal transport of dangerous goods by surface or air. To be able to ship dangerous goods, you must be trained.