Chemical, bond competitive technique

A 2.5 X 2.5 cm glass fibre matrix is fitted into a plastic case (tab) (Fig. 53). The prepared antibody can now be applied to the glass fibre matrix. The specific antibody for each test is firmly crosslinked into this matrix by a carrier antibody, the bonding by the carrier antibody being effected by a chemical bond. The specific antibody is produced in the rabbit the antibody for fixation is an anti-rabbit antibody from the goat. The glass fibre matrix is used to prevent unspecific reactions. On these carriers prepared in this manner the tests can be performed according to the competitive, sequential or sandwich technique. 

The discussion above provides the necessary elements to answer the question posed in the heading. If the intermediate does not exist (i.e., its lifetime is shorter than one vibration), the concerted mechanism is necessarily followed. Conversely, however, if the intermediate exists, the reaction pathway does not necessarily go through it, depending on the molecular structure and the driving force. Dichotomy and competition between the two mechanisms is a general problem of chemical reactivity. The example of electron transfer/bond reactions has allowed a detailed analysis of the problem, thanks to the use of electrochemical techniques on the experimental side and of semiempirical models on the theoretical side. 

The rearrangements of 1- and 2-methylbicyclo[2,l,0]pent-2-ene to methylcyclo-pentadienes has been examined in solution and in the vapour phase and a mechanism in which cleavage of the C-1—C-4 bond produces a chemically activated cyclopenta-diene, which then suffers competitive hydrogen shifts and collisional deactivation, has been advanced RRKM calculations support this conclusion. The principle of least motion technique has been applied to this and bicyclobutane rearrangements. ... 

---