How to Prepare Your Samples
Concentrating Samples: In many cases, elute proteins off some type of chromatography matrix with SDS sample buffer can keep a sample volume minimal. If the volume of sample is too large, concentrating the samples with a suitable method might be the easiest way to increase the amount of protein samples available for protein identification. Various micro-scale, protein-concentrating commercial products claim a good volume reduction with good protein recovery. Users may need to test these methods before committing their samples.
Running Gel: For SDS-PAGE, traditional Laemmli-style, Tris-Glycine gel and its various modified versions, such as Bis-Tris gel or Tris-HCl gel, are all acceptable for protein identification. Various gel concentrations are acceptable. A user should choose the type and concentration of a gel that gives the best separation for a given sample. For some reason Tris-Tricine gel seems to be less compatible with protein identification.
Staining Gel: Traditional coomassie (G-250 or R-250) staining is good for protein ID. Colloidal coomassie staining kits from various sources claim better detection limit (~ 5 ng BSA) and are all compatible with protein identification. Other staining methods, such as Zn/Cu staining, fluorescent dye staining, and silver staining are also acceptable.
Excising Protein Band: Take a photograph of a gel before cutting it. Avoid any direct contact with the gel with bare hands, light box, or any other possible sources of keratin contamination. Try to minimize the blank gel in a gel sample (it may reduce digestion efficiency and peptide recovery). Put each gel band in a clean, 1.5 ml micro-centrifuge tube and label each sample carefully.
How to Send Your Samples
Submitting Sample On-line: A first-time user will need to register before submitting a sample (approx. 3 min. process). To submit a sample, click the "Submit Sample" link and log on to your account. Then select the Protein Identification link and you will see a sample submission page. Select the number of samples you want to submit, fill in the sample information, and click "Submit". You will see the price quotation about your order on screen. Print out three (3) copies of this quotation. Send one copy to us along with your samples; use one copy as a quotation for applying a purchase order from your institute (if paid by a PO), and keep one copy for your record.
Payment: You may submit your order and ship samples to us before having a purchasing order (you need to select "No P.O. at Present" in the payment section). What your P.O. number is available, you may submit your P.O online by logging in to your account (or email/fax the P.O number to us). If you pay by a credit card, you may fill in the card information online during online submission (it is a secured link) or contact us later by phone/fax/email (please note emails may not be secure).
Shipping Sample: All samples should be shipped via a type of express service (FedEx, DHL, UPS, etc.) to minimize protein degradation. Gel samples may be shipped at room temperature with a standard envelope to minimize cost, or shipped in a container with ice packs or dry ice container to prevent possible protein degradation (it might be necessary if sample amount is very low or in a hot weather). Also, please place each gel sample in a separate 1.5 ml microtube, and then pack all sample tubes in one or more 50 ml centrifuge tubes and cap the 50ml tubes tightly to prevent possible cracking of sample tubes during shipment. Please include a copy of quotation printout and a gel picture in a sample package. All solution samples must be shipped in a dry ice container.
Checking Status: The processing of a sample will begin when we receive the samples and valid billing information. A user can monitor the status by logging on to his or her account. Please contact us if there is some abnormality in the process.
Data Delivery: Usually, we will deliver results in five business days after we have received the samples and payment information. By default, we will deliver a report to the email account provided by the customer.
Support: For technical questions regarding our service, you may send an email to support@prottech.com. We will respond to your email within 24 hours on weekdays. You may also contact us via phone or fax. We also provide free, as well as fee-based, presentation and publication support services. See "Support" for more details.