Flow-through bioassay

Intermediate condition bioassays are also found in the literature. Semi-static [2] experiments have been performed for SDS (Ci2-AS), with renewal of the water every 2 days [65] and intermittent flow-through [32], in which fathead minnows were exposed to NP for 20 days. 

LC50 (96-h) for bluegill sunfish 220 mg/L (Spehar et al., 1982), fathead minnows 193 mg/L (flow-through), 310 mg/L (static bioassay) (Alexander et al., 1978), Cyprinodon variegatus 220 ppm using natural seawater (ffeitmuller et al., 1981). 

Filtered broth was passed at 2.5 ml/min through a resin column (2.5 cm diameter, 28 cm length) packed with 150 ml of ion exchange resin Amberlite IRC-50 sodium type (Rohm and Haas Co., U.S.A.). The column was washed with water, eluted with 0.5 N HCI at a flow rate 1.3 ml/min. The eluates were fractionated each 10 ml and tuberactinomycin-N activity was found at fractions No. 45-63 obsarved by ultraviolet absorption method and bioassay. 

For cell-based Nab bioassays, it is critical to assess the stability of the cell line over time (passages) and through cryopreservation. Stability assessment should be performed by comparing assay controls such as concentration response curves or neutralizing capacity of the positive control (PC). Additional parameters, such as cell growth, appearance, and viability may also aid in stability assessment. Further, monitoring receptor expression by a method such as flow cytometry may also be valuable. 

For multiarm olfactometers, it is advisable to have a flowmeter and valve on each of the arms to ensure even airflow throughout. If only the exhaust airflow is monitored, then there may be unequal airflow through the different arms due to small constrictions, or flow restrictions if the delivery tubes are of unequal length. The bioassay chamber should be isolated from any potential visual stimuli (e.g., light sources) that may induce a preference for one arm over another. Finally, the olfactometer must be cleaned between trials, and it is strongly advisable to... 

The design of Sharpington et al. features a rectilinear wind tunnel longitudinally divided into four separate bioassay chambers. Each bioassay chamber is fitted on its upstream end with a 4 cm diameter glass cylinder that is closed with chick skin on its interior (bioassay chamber) end and connected to a constant-temperature water circulation system set to 34°C on its exterior end. Airflow is provided by a forced-air system that controls flow rate, temperature, and humidity. Notably, the airstream is purified by passing it through activated charcoal and zeolite filters, in addition. Glass partitions between the bioassay chambers separate the conditioned air into four separate odor... 

---