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DÍEZ MONTORO, R. & COL. AN. R. ACAD. NAC. FARM.

Eq. 9 contains the influence of all the studied variables. The ad-
justment of the data of Table III (n = 112) to the Eq. 9 can be ob-
served in Figure 1.

6. CONCLUSIONS

— Conclusion 1. In the reaction two process occur simultaneous-
ly, that could correspond to differents epitopes. The initial ac-
tivity of the radioactive immunocomplex (z0) is dependent on
m, as per Langmuir’s model. The apparent rate constants for
the process (kf) is independent of m.

— Conclusion 2. Activity in equilibrium (ze) is directly propor-
tional to z0, and therefore it also depends on m, as per
Langmuir’s equation. As a consequence, the RIA calibration
curves obtained with these reagents must follow the model of
the four parameters and provide a good logit-log linear fit.

— Conclusion 3. The sensitivity of the method is greater at the
most small ist he value of ze for a given value of q. Since ze in-
creases if it makes m, it agress to use low values of m. In this
way increases sesitivity without the reaction becomes slower.

— Conclusion 4. The modification of the ionic strength does not
contribute any advantage from the practical point of view.

— Conclusion 5. An increase in viscosity provides a greater sen-
sitivity of the technique. Nevertheless, it must be valued that
the reaction would become slower, with the consequent in-
crease of the incubation time.

— Conclusion 6. The sensitivity of the method is increased mak-
ing the incubation to temperatures superior to the one of the
room, whenever it does not put in danger the thermal stabili-
ty of the insulin. In addition, the reaction becomes faster.

— Conclusion 7. A theoretical model was prepared to study the ki-
netics of the substitution reaction in the immunocomplex antibody-
labelled Insuline (PM) by unlabelled Insuline (Q). Equations link-
ing PM concentration with time, M and Q concentrations, ionic
strength, viscosity, and temperature were obtained. Experimental
results were satisfactorily fitted to the theoretical model.

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