Frequently Asked Questions

Product Description

Purified, unlabeled antibody.

SPRD stands for Spectral Red® which is SouthernBiotech's registered trademark name for our PE/CY5 tandem conjugate.

"Ads" is our abbreviation of adsorption and "SP ads" is our abbreviation for serum protein adsorption.

Adsorption indicates that the product has undergone cross-adsorption during the manufacturing process to produce an antibody with minimal reactivity to the species listed in the description or technical bulletin.

For example -
SouthernBiotech Cat. No. 1070-05 (Goat Anti-Mouse IgG1, Human ads-HRP) has been cross-adsorbed against human immunoglobulins producing an antibody with minimal reactivity to human immunoglobulins.

SouthernBiotech Cat. No. 1073-05 (Goat Anti-Mouse IgG1, Human/Bovine/Horse SP ads-HRP) has been cross-adsorbed against human, bovine, and horse serum proteins producing an antibody with minimal reactivity to human, bovine, and horse serum proteins.


While we have not measured the refractive index of SouthernBiotech's Fluoromount-G® (Cat. No. 0100-01) in-house, it has been reported to be ~1.4.

Fluoromount-G® provides a semi-permanent seal rather than a hardened permanent seal.

If a permanent seal is required, some customers find it helpful to use clear fingernail polish to affix the coverslip to the slide.

Since Fluoromount-G® is water-soluble, the coverslip may be removed by submerging the slide in a PBS solution until the coverslip is loosened.

The time required will be dependent on how long the slide/Fluoromount-G® has been allowed to dry, how fragile the sample is, etc...


SouthernBiotech's specification for Low Endotoxin/Azide Free (LE/AF) products is ≤ 0.05 EU/μg as determined by LAL.

The concentrations of SouthernBiotech's HRP, AP, and BGAL conjugated antibodies are lot specific as they are diluted to potency following our quality testing to help ensure consistency between lots when using a similar working dilution.

Concentrations may be found on the lot specific Certificate of Analysis.

Since AF647 dyes cannot be excited optimally with a mercury lamp, we typically recommend its use with confocal microscopy.

Yes; however, it requires a green (532 nm) or yellow-green (561 nm) laser.

The F:P ratios of our fluorochrome conjugates are considered proprietary; however, we will be happy to provide you with a range if requested.

SouthernBiotech PE conjugated antibodies are purified by size exclusion chromatography following conjugation to remove unbound dye/antibody.

The final product contains a mixture of labeling ratios (some 1:1, some 2:1, etc...).


The recommended storage temperature of SouthernBiotech's Gelatin Subbed Slides is -70°C.

This temperature aids in the inhibition of algae growth for the duration of the shelf life of the product (15 months from the date of manufacture).

Storage at -20°C or ambient temperatures for a short period of time should not affect the performance of the product.

Below is a brief explanation of SouthernBiotech's lot numbering system -

For SouthernBiotech's Streptavidin-HRP (SB Cat. No. 7105-05; Lot No. G5206-V605H), the Base Lot No. (G5206) indicates the purified/unlabeled batch of material while the Ending Lot No. (V605) indicates modification (conjugation to HRP in this case).

A letter at the end of the lot number (H) refers to an internal codification system that we use to denote different packaging events of the material.

Therefore, Lot No. G5206-V605B and Lot No. G5206-V605H are the same lot of material which were simply packaged on different dates.

SouthernBiotech products are guaranteed through the expiration date listed on the vial label if stored undiluted as directed on the technical bulletin upon receipt of the product.

The remaining shelf life of our products is 9 - 15 months from the date of shipment.

Unless otherwise requested by the customer, SouthernBiotech ships the majority of its purified and conjugated antibodies at ambient temperature.

Our practical shipping experience has indicated that these products are stable for a minimum of five (5) days at ambient temperature without appreciable loss of activity.

Extracellular Matrix Reagents

Collagen proteins can be inconsistent on SDS-PAGE in comparison to typical globular proteins.

Additional information regarding this subject may be found - here.

SouthernBiotech polyclonal anti-collagen antibodies are quality tested by ELISA or FLISA on a panel of purified collagen standards (I, II, III, IV, V, or VI) to ensure positive reactivity/specificity to their respective collagen target and minimal reactivity to the remaining five collagens.

Working Dilution

For our HRP and AP conjugated secondary antibodies, a dilution of 1:4,000 - 1:8,000 is typically recommended as a starting point to begin optimization.

Please note that since applications vary, you should determine the optimal working dilution for the product that is appropriate for your specific needs.


SouthernBiotech Cat. No. 10040-01 is expressed in E. coli and SouthernBiotech Cat. No. 10039-01 is expressed in eukaryotic cells.