Collagen is an inert, rigid protein found predominantly in skin, ligaments, bones and teeth. Its most distinctive attribute, essential to a transmitter of mechanical force, is inelasticity. Its fundamental structural unit is tropo-collagen, a molecular rod about 2600Å in length and 15Å in diameter and 300,000 molecular weight. In tendons these macromolecules, grouped as collagen fibrils, run parallel to the axis. In skin the fibrils are interlaced and branched.

1. Type II or type I collagen-coated 8 well strips a) Four, 8-well strips which are uncoated to serve as a control.. Two strips are used per run allowing two partial plates to be run two separate occasions. b) Five, 8-well strips coated with either CII, BII, PII and HII (Human Type II ELISA) or coated with either CI, BI, PI and HI (Human Type I ELISA). c) Four, 8-well strips to be used for standards. 2. Standard antibody (1.1ml, 16units/ml) 3. Solution A (Blocking buffer, 15ml) 4. Solution B (Sample dilution buffer, 60ml): Use for diluting the standard and sample specimens. 5. Secondary antibody (two vials of biotin-conjugated goat anti-human IgG, lyophilized): Dissolve one vial in 10ml Solution C-1. 6. Solution C-1 (Secondary antibody dilution buffer, 20ml). 7. Peroxidase-conjugated Streptavidin (two vials) Dissolve one vial in 10ml Solution C-2. 8. Solution C-2 (Avidin-Peroxidase dilution buffer, 2 ml) 9. Urea-H2O2 plus buffer tablet (two tablets). Dissolve one tablet in 20 ml glass-distilled water. 10. OPD tablet (two tablets): Dissolve one tablet in 20ml Urea-H2O2 buffer prepared in step 9, just before use. 11. Solution D (Stop solution: 7.5ml of 2.5N Sulfuric acid). 12. Solution E (20X Wash buffer, 50ml): Dilute in 1 liter of distilled water.

Store components at 4°C. Stable for 6 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.