Refer to the package insert for each product. If you have further questions, contact VitaCyte technical support.
How do I store solubilized enzymes after use?
Refer to the package insert for each product. If you have further questions, contact VitaCyte technical support.
How do I reconstitute your lyophilized products?
Refer to the package insert for each product. If you have further questions, contact VitaCyte technical support.
Guide to abbreviations used to label VitaCyte’s products or technical support literature.
Product abbreviations: Collagenase HA = purified collagenase with high collagen degradation activity (CDA) Collagenase MA = purified collagenase with moderate CDA (about 50% of Collagenase HA) BP Protease = neutral protease from Bacillus polymyxa (DispaseTM Equivalent enzyme) DE Collagenase = Defined Enriched collagenase CIzyme RI = application specific enzyme mixture for rodent islet isolation CIzyme
Why don’t you offer a formulation for my specific application?
There are over 200 mature cell types in mammals. A limited number of these cells are routinely used for research studies. These include islets and acinar cells from the pancreas, hepatocytes and non-parenchymal cells from the liver, cardiomyocytes, neural cells, and different types of kidney cells. For many of these cells, VitaCyte provides a product,
What are application specific formulations?
Application Specific Formulations are pre-blended mixtures of purified collagenase and protease in optimal ratios for isolation of cells from a particular tissue and/or species. These formulations provide a recommended dose for use with an associated method. These effectiveness of these product to isolate specific cell types was demonstrated by several different laboratories. Currently, VitaCyte offer
How do I transition from a Sigma, Worthington, or Nordmark collagenase product to a VitaCyte collagenase product?
This is dependent on the cell you are isolating. VitaCyte has enzyme product/formulations and recommended doses to isolate: Rodent Islets Porcine Islets Non-Human Primate Islets Human Islets Rodent and Human Hepatocytes Rodent Cardiomyocytes Human Adipose These recommendations can be found on the Applications page. For other cells, view the other cells page that translates the
Can you provide conversions factors to translate enzyme activities from other vendors into VitaCyte’s enzyme units so I know which product to evaluate?
It is difficult to come up with a reliable conversion factors to translate enzyme activities from one supplier to those from another supplier. Some of the factors that may affect this value are differences in the assay precision by one or both suppliers, differences in the protein or derivatized substrates to detect the activity of
My technician forgot to put our latest shipment of enzymes in the freezer. They sat overnight at ambient temperature. Are they still usable?
The DE Collagenase, Collagenase Gold, Collagenase Gold Plus, BP Protease, and CIzyme AS products are stable for several days at ambient temperatures. For other products, contact VitaCyte technical support.
How do I convert dimethylcasein (DMC) units into FITC-BSA Units?
To convert DMC units to FITC-BSA units, multiply the DMC units by 13,400. For example, if you are currently using 1.75 DMC U per gram then you would target 23,450 FITC-BSA units for equivalent activities.
How do I convert the concentration (mg/mL) of Dispase II I currently use into FITC-BSA Units/mL reported by VitaCyte?
The DispaseTM II product is a cruder preparation of neutral protease than our CIzyme™ BP protease, but both originate from Paenibacillus polymyxa fermentations . The FITC-BSA specific activity of the Dispase II product is less than 10% that of our CIzyme™ BP Protease and can vary dramatically between lots. To substitute CIzyme™ BP Protease for
Are your enzymes approved for clinical use?
To be determined. VitaCyte’s products are labeled for research use only or as GMP Grade. All products are manufactured in accordance with the principles for clinical trial material outlined in the International Conference on Harmonization (ICH) document ICH Q7A, “Good Manufacturing Practice Guidance for Active Pharmaceutical Ingredients”. The GMP Grade products are bottled and lyophilized
What are the optimal temperatures for maximal collagenase and protease activity?
Temperatures in the range of 35-37°C will result in maximum activity of collagenase degradation of native collagen. A 5°C reduction in temperature (30°C) will result in an approximate 60% loss of maximal activity for class 1 and class 2 collagenase. In contrast, the neutral proteases BP Protease and thermolysin are less dramatically affected by temperature
Do I have to supplement the purified collagenase with a protease source?
Yes. VitaCyte’s collagenase products are chromatographically purified to minimize contamination of protease. Collagenase with negligible protease contamination ensures minimal loss of collagen degradation activity during storage or as a frozen solution. Purified collagenase alone is ineffective in releasing cells from tissue since protease activity is required to degrade other extracellular matrix proteins (see Mechanism FAQs).
Are your enzymes sterile?
No. VitaCyte’s purified collagenases and neutral proteases, as well as our application specific formulations, are all aseptically dispensed in a biological safety cabinet located within a controlled environment. To ensure sterility, we recommend the user filter the enzyme solution through a 0.2 µm sterile filter immediately before use.
Why is your collagen degradation units per mg different than other vendors?
These results cannot be compared since different substrates and assay principles are used to measure this activity. VitaCyte’s kinetic fluorescent microplate CDA assay detects an increase in fluorescence as collagenase unravels and degrades fluorescein isothiocyanate conjugated to collagen fibrils. Measurements are made every 150 seconds. By contrast, the Mandl is an endpoint assay where collagenase
What is the difference between the CIzyme Collagenase HA and CIzyme Collagenase MA products?
CIzyme Collagenase HA (high activity) and MA (moderate activity) differ only in the amount of truncated class 1 (C1) collagenase present. Truncated C1 is defined as that form of C1 that has lost the carboxy terminal collagen binding domain. Truncated C1 has a mass about 90% of intact C1. Both HA and MA are 60%:40%
Can I freeze the unused portion of the reconstituted collagenase and use it at a later time?
Yes. Internal studies have shown the reconstituted collagenase is stable as a frozen solution between -15 to -25°C for at least 1 year as long as no other protease enzymes have been added to the collagenase solution. For ensured stability it is best to minimize the volume used for dissolution and reconstitute with water or
What buffer should I use to reconstitute the lyophilized enzyme?
We recommend using sterile or RODI water for the initial reconstitution of the lyophilized protein. For details, refer to the products’ package insert. After dissolution, dilute the enzyme to the appropriate volume for use in your application. If you want to use a solution other than water to reconstitute the lyophilized protein, avoid using solutions