Photodynamic tissue adhesion with chlorin(e6) protein conjugates.
OBJECTIVE
To test the hypothesis that a photodynamic laser-activated tissue solder would perform better in sealing scleral incisions when the photosensitizer was covalently linked to the protein than when it was noncovalently mixed.


METHODS
Conjugates and mixtures were prepared between the photosensitizer chlorin(e6) and various proteins (albumin, fibrinogen, and gelatin) in different ratios and used to weld penetrating scleral incisions made in human cadaveric eyes. A blue-green (488-514 nm) argon laser activated the adhesive, and the strength of the closure was measured by increasing the intraocular pressure until the wound showed leakage.


RESULTS
Both covalent conjugates and noncovalent mixtures showed a light dose-dependent increase in leaking pressure. A preparation of albumin chlorin(e6) conjugate with additional albumin added (2.5 protein to chlorin(e6) molar ratio) showed significantly higher weld strength than other protein conjugates and mixtures.


CONCLUSIONS
This is the first report of dye-protein conjugates as tissue solders. These conjugates may have applications in ophthalmology.
Khadem
J
J
The Retina Specialists of Boston, Harvard Medical School, 02114, USA. jkhadem@vision.eri.harvard.edu
Veloso
A A
AA
Tolentino
F
F
Hasan
T
T
Hamblin
M R
MR
D002735:Chlorophyllides; D005340:Fibrinogen; D005780:Gelatin; D006801:Humans; D007429:Intraocular Pressure; D007834:Lasers; D010539:Permeability; D010778:Photochemotherapy; D011166:Porphyrins / Q000627:therapeutic use*; D012590:Sclera / Q000187:drug effects*; D012710:Serum Albumin, Bovine; D013536:Suture Techniques; D014014:Tissue Adhesives / Q000627:therapeutic use*; D014945:Wound Healing
D002735:Chlorophyllides; D011166:Porphyrins; D014014:Tissue Adhesives; D012710:Serum Albumin, Bovine; C062985:phytochlorin; D005780:Gelatin; D005340:Fibrinogen