Reagent FAQs

How can I order?

Orders can be placed by email directly through customer service or via NKMAX’s online ordering system.

If a product of interest is clicked, it can be added to cart by clicking on that option in the upper part of the datasheet. To complete the purchase, the “Check Out" option has to be pressed and from there billing and shipping information has to be provided.

Once a purchase is made, a confirmation page will appear and the invoice can be printed. An email with purchasing information will also be automatically sent. The following day an email confirming the delivery time and availability of the product will be sent by an NKMAX sales team.

If no delivery confirmation emails has been sent within 24hours except during weekends including Fridays or if any other problems occur during purchasing, please email us at

How much is shipping and what is the lead time?

Depending on location shipping usually takes 2 to 3 days. An email with the tracking number and details of the shipment is sent as soon as an order is shipped. We mainly use Fedex since they have provided the most reliable delivery service for our proteins and antibodies in all the years that we have been in business.

To calculate how much shipping is for you, select your country in the drop down menu below, and your shipping cost will appear.

Select country :

Shipping cost : $65.00

We ship every day of the week except Thursdays, as to avoid having them spend the weekend at a customs office or a local courier’s office. Our packaging consists of Antigens frozen in plastic vials, sealed in vacuumed vinyl bags, and placed in a styrofoam box with four ice packs. The styrofoam box is taped as to be sealed and inserted into a cardboard box. We have found it to be the safest way to guarantee the stability of our products. If you request special packaging we may be able to ship it in accordance to your preference and charge its relative cost difference.

For further inquiries regarding shipping, please contact us.

How can we change our order?

Options to remove items from cart or modify quantities are available by clicking on "Cart" on the top of the screen.

What are your refund, return and cancellation policies?

Our scientific experts will examine details of your protocol to determine whether the problem is protocol related or product related:

  • For protocol-related problems, our experts will give you independent professional advice.
  • For product-related problems, a replacement or refund will be offered.

If you do not provide details of your protocol or follow the recommendations of our experts, NKMAX will unfortunately be unable to issue a replacement or refund.

This offer is only valid for products purchased directly from NKMAX and its authorized distributors.

If an order or part of an order is cancelled for any reason by a customer after a shipment is made or while the ordered product is being manufactured within the agreed lead time, there will be a cancellation penalty fee of 30% of product invoiced price, in addition to any shipping, handling and packaging costs if applicable. This is to help us recover the resources spent on the timely manufacturing or shipping of our client’s order and to share responsibility between us.

How can we pay?

Payments can be done by credit card, checks, or wire transfers. All purchases should be paid within 30 days of the purchased goods’ delivery (Net30). If Net 30 payment is chosen and you want to pay by credit card then, we can email you a credit card payment link via PayPal upon request by email. You do not need a PayPal account to pay via PayPal’s payment system.

How long does it take to receive our shipment after we place an order?

It usually takes 2 to 4 days depending on where you are located.

If I have a problem with our product, who do I contact?

You can email us at, and you will receive a reply promptly.

Our staff will be happy to answer any questions, and all our products are guaranteed if they don't work as indicated in our datasheets.

How can I cancel or change an order, and how long do I have?

You can cancel your order by logging into your account and change it in the order section, or by simply emailing us directly at

Because all sales are final when you product is dispatched, if you haven’t received an email confirming shipment, there shouldn’t be any problems to cancel your order.

Who do we contact for our ordering and technical questions?

Please email us at for ordering questions and for technical enquiries.

Can I get a free sample?

We do not normally offer free samples. However, if you feel you have special reasons for obtaining a sample of our antibodies or recombinant proteins, please feel free to contact us so we can find a possible solution. Buying our proteins and antibodies is risk free. We replace any of our products that don't work as indicated in our datasheets. This policy greatly reduces the need for samples.

Can I get a discount?

We offer discount only on “bulk” purchases of five vials or more. Please contact us by email at to request a discount.

Will the antibody I’m interested in work even if it isn’t validated for the species I want?

We cannot guarantee that an antibody will work for a species that has not been validated. However, using the sequence of the protein that was used to make the antibody you can do a sequence alignment analysis of the desired species against the antibody of interest. This will help you evaluate the probabilities of cross reaction. You can find an online sequence program called Sim at, and you can search protein sequences on NCBI at, (or Swissprot at We recommend 80% or more of the sequences to match for cross reactivity. If the antibody was generated using a peptide, an alignment should be done between the peptide sequence and its full protein sequence. We usually include the antigen sequence in our datasheet. However, if you cannot find the peptide immunogen sequence on our documentation, please email us at

How should I choose a suitable secondary antibody?

Secondary antibodies should be raised against the host species of the primary antibody you are using. For example, if your primary is a mouse monoclonal, you will require an anti-mouse secondary.

How should I choose a positive control?

If you require a suitable positive control, please check the datasheet since it usually includes a suggested positive control. You should use the tissue or cell line from a tested species. Not all our datasheets have a suggested suitable control, but we always try to include it.

Why is the actual western blot band size different from the predicted?

Western blotting is a technique that separates proteins based on size. In general, the smaller the protein the faster it migrates through the gel. However, migration is also affected by other factors, so the actual band size observed may differ from that predicted. Here are some common factors:

  1. 1.Splice variants - splicing may create different sized proteins (mutant form) produced from the same gene.
  2. 2.Post-translational modification - e.g. glycosylation, phosphorylation, cleavage etc, can increase or decrease the size of the protein.
  3. 3.Relative charge - the composition of amino acids (charged vs non-charged)
  4. 4.Multimers - e.g. dimers, trimers, or oligomers that have stronger affinities may have different mobility on SDS-page.

We aren’t getting a positive signal from the antibody we purchase from you. What should I do?

First we suggest testing it with our western blot protocol. Please contact us if the problem persists. We will help you find a solution and if the product was faulty we will replace it at no cost (“no cost” means just that: we pay for shipping.)

Our General Western Blot Protocol:

  1. 1.Sample: Cell lysates 30ug/well* and recombinant protein 100ng/well* loaded.
  2. 2.Sample preparation: SDS loading buffer was added to the cell lysates and recombinant protein. This solution was boiled before loading on a 15% SDS-PAGE
  3. 3.Blocking: 5% skim milk in PBS-Tween, for 1hr at room temperature, 3 times x 10 min PBS-tween washes
  4. 4.Primary antibody: Primary antibody 1:1,000*, at 4℃ overnight, 3 times x 10 min PBS-tween washes
  5. 5.Secondary antibody: Goat anti-mouse HRP conjugated 1:1,000, for 1hr at room temperature, 3 times x 10 min PBS-tween washes
  6. 6.Development: ECL

* These amounts may change according to the specifications on our datasheets. For further enquirires about a specific product you can contact us at

What is the shelf life of your recombinant proteins and antibodies?

Can be stored at +2C to +8C for 1 week. For long term storage, aliquot and store at -20C to -80C. Avoid repeated freezing and thawing cycles.