Two-layer film as a laser soldering biomaterial

Background and Objectives: A two-layer solder was developed to weld at low laser intensity and to provide a new method of measuring solder-tissue temperature. Study Design/Materials and Methods: A film solder consisted of a white layer (bovine serum albumin (BSA) and distilled water) and a black layer (BSA, carbon black (CB), and distilled water). This two-layer solder was used with a diode laser to weld sections of dog small intestine (λ = 810 nm, power = 200 ± 20 mW, radiation dose = 18 ± 1 J/mg). Sections of intestine were welded only with one-layer black solders as control group. The temperature difference between the external solder surface and the tissue- solder interface was evaluated during welding. Results: The two-layer solder performed welds as strong as the one-layer solder (~0.12 N) but with less laser intensity on the black layer. The temperature difference between the external surface of the solder and the solder-tissue interface was significantly less for the two-layer solder than for the one-layer solder (~6°C and ~15°C, respectively; P < 0.05). Conclusions: The two-layer solder appeared to be more efficient at soldering biomaterials than the one- layer solder. Furthermore, the heat diffusion from the black midplane of the two-layer solder decreased the difference in temperature recorded on the solder external surface and on the solder-tissue interface.