We currently offer PolyHRP conjugates in two liquid forms. One is concentrated stock
solution for long term -20° storage. Another is pre-diluted in PolyHRP Stabilizer format
for storage at +2°C/+8°C.

Our standardized stock PolyHRP conjugate solutions are 1 mg/ml total
chromatographically purified conjugate in cryopreserved liquid formulation containing
50% Ultra-pure glycerol, general protein stabilizer (Ultra-pure biotin-free BSA), special
protohematin/HRP stabilizer and BND as biocide preservative. Cryopreserved stock
PolyHRP conjugate solutions feature excellent stability when stored at -20°C in tightly
closed vials.

There are no strict requirements to packaging material when storing stock PolyHRP
batches at -20°C. We currently have available data proving 100% activity maintenance
with conjugate back-up samples stored up to 6-8 years at -20°C in both
neutral/borosilicate type I glass, PET/PETG/PC (low oxygen permeability materials) and
regular PP/PE-HD (oxygen permeable) bottles/vials.

Cryopreserved stock conjugate solutions will remain liquid at temperatures down to -25°C.
Stock solutions will freeze at temperatures below -25°C. Freezing conjugates at lower
temperatures is not recommended.

Neither of PolyHRP conjugates is filterable through 0.2m or smaller pore size filters. Re-
filtering of concentrated stock PolyHRP conjugate solutions is not needed and not

Re-filtering of pre-diluted and ready-to-use conjugate forms, if these are made of properly
stored stock conjugate solution (or pre-diluted item) and PolyHRP Stabilizer of SDT at
customers place in adequately clean conditions, when risk of contamination is minimized,
is also not necessarily needed and not recommended.

If you do wish to re-filter liquid formulation containing PolyHRP conjugate, use 0.45m-
filters. This is the smaller filter pore size compatible with the PolyHRP. Best are the
cellulose acetate filters with GF pre-filter mounted in single filter unit, e.g. 0.45 m
MiniSart Plus of Sartorius.

Do not use 0.2m filter units! See our PolyHRP Users Guide for more details on
handling PolyHRP conjugates.

Auxiliary products ideally compatible with PolyHRP conjugates are as follows:

SA-PolyHRP line:

ready-to-use products

- Universal Casein Diluent/Blocker #UCDB

- SA-PolyHRP Stabilizer #SA1

- SA-PolyHRP Stabilizer RHT (Realtime High Temperature) #SA3-RHT

intermediate products

- Casein Buffer Concentrate 1 #CBC1

Other (Protein A, Secondary Antibody & Custom) PolyHRP conjugates:


- Universal Casein Diluent/Blocker #UCDB

- SA-PolyHRP Stabilizer #SA1

- SA-PolyHRP Stabilizer RHT (Realtime High Temperature) #SA3-RHT

- Antibody/Antigen/Conjugate Diluent/Blocker #AADB

- Antibody/Antigen (PolyHRP) Conjugate Stabilizer #AA1

- Antibody/Antigen (PolyHRP) Conjugate Stabilizer RHT
(Realtime High Temperature) #AA3-RHT


- Casein Buffer Concentrate 1 #CBC1

- Casein Buffer Concentrate 2 #CBC2