Lead Discovery Services

BioAssay Systems has developed a range of assays for performing lead optimization and characterization. Our lead discovery services include, but are not limited to, ADMET Services, Enzyme Inhibitor Screening, and Phosphorylation Status Screening.

Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET). BioAssay System's ADMET services are ideal for early stage drug discovery and specialized for evaluating test compounds as drug candidates. Screen for leads by testing for absorption, distribution, metabolism, excretion, and toxicity.

Absorption. Solubility determination by
Distribution
Toxicity

If the ADMET service you are interested in is not listed, please contact us with your project details and we will evaluate the project feasability.

Enzyme Inhibitor Screening. BioAssay Systems enzyme inhibitor screening services are optimized for modern lead discovery. Evaluate test compounds in regards to their activating or inhibitory effects on the enzyme(s) of interest. Our enzyme inhibitor screening services include, but are not limited to, determination of EC50 or IC50 and mode of action for lead compounds.

Determine Enzyme Km
Substrate titration on the enzyme of interest followed by analysis with graphing software determines the Km. Once the Km has been established, this substrate concentration is then used for the inhibitor screening.

Substrate K<sub>m</sub> Graph

Measure Solvent Interference
To test for solvent interference, we titrate the solvent with the enzyme of interest and look for any increase or decrease in enzyme activity. If there is interference, we determine the solvent concentration at which interference becomes negligible. This solvent concentration is then used for the inhibitor screening.

Solvent Interference Graph

Determine Inhibitor IC50
A titration of the inhibitor in the solvent is incubated with the enzyme of interest. After incubation with the inhibitor, enzyme activity is measured using Km for substrate concentration. The inhibition data is plotted with graphing software and the inhibitor IC50 is determined.

Inhibitor IC50 Graph

Available Enzymes
  • Acid Phosphatase
  • Aconitase
  • Alkaline Phosphatase
  • Amylase
  • Arginase
  • Aspartate Transaminase
  • Catalase
  • Creatine Kinase
  • Diamine Oxidase
  • Fumarase
  • Glucose Oxidase
  • Glucose-6-Phosphate Dehydrogenase
  • Glutamate Dehydrogenase
  • Glutathione Peroxidase
  • Glutathione Reductase
  • Glutathione S-transferase
  • Glyoxalase
  • Invertase/Sucrase
  • Isocitrate Dehydrogenase
  • Kinase
  • Lactate Dehydrogenase
  • Lipase
  • Malate Dehydrogenase
  • Mannosidase
  • Monoamine Oxidase
  • Myeloperoxidase
  • Neuraminidase
  • Nitric Oxide Synthase
  • Phosphatase
  • Phospholipase D
  • Pyruvate Kinase
  • Sorbitol Dehydrogenase
  • Superoxide Dismutase
  • Urease
  • Xanthine Oxidase

Examples of Past Inhibitor Screening Services
  • Arginase Inhibitor Assay.
    Arginase is a drug target for various diseases, such as cancer, hypertension, atherosclerosis, myocardial ischaemia, congestive heart failure, and diabetes mellitus. More details.

  • PTP1b Inhibitor Assay.
    Protein tyrosine phosphatase 1B (PTP1B) is a key regulator and primary drug target for type 2 diabetes and obesity. It is also involved in liver regeneration, drug-induced liver disease, non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma. More details.

  • Monoamine Oxidase Inhibitor Assay.
    Monoamine oxidase is involved in removing the neurotransmitters norepinephrine, serotonin and dopamine from the brain. Monoamine oxidase inhibitors (MAOIs) were the first type of antidepressant developed. More details.

  • Acetylcholinesterase Inhibitor Assay.
    Acetylhydrolase is the primary cholinesterase that catalyzes the breakdown of acetylcholine and other choline esters that function as neurotransmitters. Acetylcholinesterase inhibitor is a drug that inhibits the breakdown of acetylcholine, thus increasing both the level and duration of action of the neurotransmitter acetylcholine. More details.

  • Aldehyde Dehydrogenase Inhibitor Assay.
    Aldehyde Dehydrogenases (ALDHs) are a family of enzymes crucial to alcohol metabolism, catalyzing the breakdown of acetaldehyde. Elevated levels of ALDHs have also been associated to certain cancer types. Cancer Stem Cells (CSCs) with heightened levels of ALDHs have shown enhanced survival mechanisms leading to resistance to chemotherapy and radiation. More details.

If the enzyme you are interested in is not listed here, please contact us with your enzyme of interest and we will evaluate the project feasibility.

Phosphorylation Status Screening. BioAssay Systems' phosphorylation status screening services are for evaluating changes in cell signaling as a result of exposure to test compounds. The services allow the screening of phosphorylation status modulators in important cell signalling pathways. Our phosphorylation status services include, but are not limited to, determination of species reactivity and phosphorylation kinetics as well as the EC50 or IC50 for test compounds.

Species Reactivity
Analyzing the test compound's reactivity with different cell species.

Species Reactivity Graph

Test Compound Titration
A titration is run on the test compound to determine its effects and whether it activates or inhibits phosphorylation.

Test Compound Titration Graph

Phosphorylation Kinetics
The phosphorylation kinetics for the test compound are measured at a specific dosage.

Phosphorylation Kinetics Graph

IC50 Determination
To determine the IC50, we run a titration on the concentration of the test compound.

IC50 Determination Graph

Examples of Past Phosphorylation Status Screening Services
  • ERK Phosphorylation Status.
    The mitogen-activated protein kinase (MAPK/ERK) pathway plays a key role in cell proliferation, differentiation and migration. Stimulation by mitogens eventually leads to phosphorylation of ERK1 (T202/Y204) and ERK2 (T185/Y187). The MAPK/ERK cascade presents many interesting drug targets for the development of cancer therapies. More details.

  • AMPK Phosphorylation Status.
    The 5-AMP-activated protein kinase (AMPK) is a key sensor of intracellular energy balance. AMPK is activated in response to an increase in the AMP/ATP ratio, which can be caused by a number of factors such as muscle contraction, starvation, or hypoxia. AMPK is activated by phosphorylation on Thr-172 within the catalytic domain. AMP binding results in a 2 to 5-fold increase in AMPK activity compared to the basal level. More details.

  • NFκB Phosphorylation Status.
    Nuclear factor-kappa B (NFκB) is a transcription factor that plays a central role in many physiological processes (e.g. inflammation, tumorigenesis, and apoptosis). NFκB is activated by a wide variety of stimuli, including inflammatory cytokines such as TNF-α. Phosphorylation of p65/RelA at Ser-536 results in decreased nuclear export and enhanced p65/RelA-dependent transcription. More details.

If the phosphorylation status screening you are interested in is not listed here, Please contact us by email, or call us at 1-510-782-9988 x 2 to discuss your service needs.

Customer Testimonials
Edward T. Wei, Chief Scientific Officer, Orinda Pharma, Inc.
"It is a pleasure working together with BioAssay Systems. I brought samples to their Hayward location and received the results in less than 24 hr. The discussion with Robert Z was courteous, open, and with a depth of knowledge. Robert has a PhD from Stanford. Also, Frank Huang, the CEO, had sufficient scientific curiosity to try out our cleanser and provide feedback! This is beyond the call of customer relations. BioAssay Systems is a company with a lot of expertise and a friendly, responsive approach to problem solving. I will enthusiastically continue to work with them to carry out our research."

Anh-Dung Le, CEO DermaTec LLC
"The guys at BioAssay Systems know their science! I had to develop a bioassay for our company and Robert was very quick to respond to keep us up to date. They are knowledgeable and very resourceful. They directed us to one of the bulk suppliers that could give us a really good deal on our active ingredient. They keep very detailed records for our research needs. I would recommend working with BioAssay Systems on your assay development projects!"