We offer IgY antibodies to 6xHis, GST, and GFP. Please note that unmodified versions have been tested in applications as stated in product details. Modified versions are lightly modified to preserve binding properties, but have not been subsequently tested. As in all research, the end user is advised to use appropriate positive and negative controls. Larger quantities are available at a discount. Inquire for details. If your research demands an antibody not listed here, please contact us for custom production services. A variety of services are available, at prices starting as low as $500.