Table 1a.

PACK-CXL Protocol Details: Pepsin Digestion Assay

				Chromophore
Experiments	Fluence [J/cm2]	Intensity [mW/cm2]	Total Irradiation Time [min]	Type	Concentration	Carrier	Replenishment	Sample Size
1: Acceleration
Control	0	0	0	–	–	–	–	28
30 min	5.4	3	30	Riboflavin	0.1%	Dextran	yes	36
10 min	5.4	9	10	Riboflavin	0.1%	Dextran	yes	36
2 min	5.4	45	2	Riboflavin	0.1%	Dextran	yes	35
2: Fluence
Control	0	0	0	–	–	–	–	59
5.4 J/cm2	5.4	9	10	Riboflavin	0.1%	Dextran	yes	30
10.8 J/cm2	10.8	9 + 45	12	Riboflavin	0.1%	Dextran	yes	30
16.2 J/cm2	16.2	9 + 2 × 45	14	Riboflavin	0.1%	Dextran	yes	30
21.6 J/cm2	21.6	9 + 3 × 45	16	Riboflavin	0.1%	Dextran	yes	56
27 J/cm2	27	9 + 4 × 45	18	Riboflavin	0.1%	Dextran	yes	29
32.4 J/cm2	32.4	9 + 5 × 45	20	Riboflavin	0.1%	Dextran	yes	29
3: Riboflavin concentration and D2O supplementation
Control	0	0	0	–	–	–	–	25
0.1 Riboflavin	5.4	9	10	Riboflavin*	0.1%	Dextran	yes	25
0.1 Riboflavin + D2O	5.4	9	10	Riboflavin*	0.1%	Dextran + 30% D2O	yes	25
0.4 Riboflavin	5.4	9	10	Riboflavin*	0.4%	Dextran	yes	25
0.4 Riboflavin + D2O	5.4	9	10	Riboflavin*	0.4%	Dextran + 30%D2O	yes	25
4: Riboflavin carrier
Control	0	0	0	–	–	–	–	38
HPMC	5.4	9	10	Riboflavin	0.1%	HMPC	yes	42
Dextran	5.4	9	10	Riboflavin	0.1%	Dextran	yes	42
5: Riboflavin replenishment
Control	0	0	0	–	–	–	–	13
Yes	16.2	9 + 2 × 45	14	Riboflavin	0.1%	Dextran	yes	14
No	16.2	9 + 2 × 45	14	Riboflavin	0.1%	Dextran	no	14

^*Commercial product not available, prepared by pharmacist. Two commercial products used: Riboflavin solution for Corneal Cross-Linking (CXL), Peschke D, PESCHKE Trade GmbH, Huenenberg, Switzerland; and Riboflavin solution for Corneal Cross-Linking (CXL), Peschke M, PESCHKE Trade GmbH, Huenenberg, Switzerland.