Method of determining metabolism of a test agent

1. A method for detecting one or more metabolites of a test agent in a tissue comprising:

A) incubating a test agent and an enzyme within a three-dimensional structure comprising a first mold or polymer scaffold, a semi-permeable membrane, and a second mold or polymer scaffold, wherein the semi-permeable membrane is disposed between the first and second molds or polymer scaffolds, and wherein the first mold or polymer scaffold has microchannels that form a fluidic branching network that mimics the forces and transport of natural vasculatures and wherein the second mold or polymer scaffold comprises cells;

B) forming an enzyme-substrate complex between the enzyme and the test agent; and

C) detecting one or more metabolites of the test agent.

2. The method of claim 1 , wherein the structure comprises liver tissue, kidney tissue, cardiac tissue, cartilage tissue, or bone marrow tissue, and combinations thereof.

3. The method of claim 1 , wherein the test agent comprises a compound selected from the group consisting of opioid analgesics, anti-inflammatory drugs, diuretics, cardiovascular drugs, cardiac drugs, agents that affect hyperlipoproteinemias, anti-neoplastic agents, immunomodulators, anti-diabetic agents, and anti-microbial agents.

4. The method of claim 1 , wherein the enzyme is selected from the group consisting of cytochrome P450, alkaline phosphatase, α-galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, α-glucuronidase, β-glucuronidase, α-amylase, NADPH-cytochrome P450 reductase, cytochrome b 5 , N-demethylase, O-demethylase, acetylcholinesterase, pseudocholinesterase, epoxide hydrolase, amidases, uridine diphosphate (UDP)-glucuronosyltransferases, phenol sulfotransferase, alcohol sulfotransferase, sterid sulfotransferase, and arylamine sulfotransferase, UDP-glycosyltransferases, purine phosphoribosyltransferase, N-acetyltransferases, glutathione S-transferase, phenylethanolamine N-methyltransferase, non-specific N-methyltransferase, imidazole N-methyltransferase, catechol-O-methyltransferase, hydroxyindole-O-methyltransferase, S-methyltransferase, alcohol dehydrogenase, aldehyde dehydrogenase, xanthine oxidase, monoamine oxidases, diamine oxidases, flavoprotein N-oxidases, hydroxylases, aromatases, cysteine conjugate β-lyase, and alkylhydrazine oxidase.

5. The method of claim 1 , wherein the enzyme is endogenously expressed in the tissue.

6. The method of claim 1 , wherein the enzyme has normal enzymatic activity compared to an enzyme containing a polymorphism or mutation and having altered enzymatic activity.

7. The method of claim 1 , wherein the enzyme contains a polymorphism or mutation.

8. The method of claim 1 , wherein the enzyme is a recombinant enzyme.

9. The method of claim 1 , wherein the enzyme is cytochrome P450.

10. The method of claim 1 , wherein the one or more metabolites are detected by liquid chromatography, mass spectrometry, nuclear magnetic resonance, or spectrophotometry.

11. The method of claim 1 , wherein the membrane is endothelialized.

12. The method of claim 1 , further comprising circulating a physiological fluid through the microchannels, wherein the physiological fluid is selected from the group consisting of media, blood, plasma and combinations thereof.

13. The method of claim 3 , wherein the anti-inflammatory drugs are selected from the group consisting of antihistamines and non-steroidal anti-inflammatory drugs (nsaids).

14. The method of claim 3 , wherein the diuretics are selected from the group consisting of carbonic anhydrase inhibitors, loop diuretics, high-ceiling diuretics, thiazides and potassium-sparing diuretics.

15. The method of claim 3 , wherein the cardiovascular drug is an angiotensin converting enzyme inhibitor.

16. The method of claim 3 , wherein the cardiac drugs are selected from the group consisting of organic nitrates, calcium channel blockers, sympatholytic agents, vasodilators, β-adrenergic receptor agonists, β-adrenergic receptor antagonists, cardiac glycosides and anti-arrhythmic drugs.

17. The method of claim 3 , wherein the agent that affects hyperlipoproteinemias is a 3-hydroxymethylglutaryl-coenzyme a (hmg-coa) inhibitor.

18. The method of claim 3 , wherein the anti-neoplastic agents are selected from the group consisting alkylating agents and antimetabolites.

19. The method of claim 3 , wherein the anti-microbial agents are selected from the group consisting antibiotics, antibacterial agents, antiviral agents, antifungal agents, antiprotozoal agents and antihelminthic agents.