Spectrophotometric determination of LAP photoinitiator radicalization in ophthalmic applications
Data files
Feb 24, 2026 version files 25.59 KB
-
LAP_datasets_final.zip
21.50 KB
-
README.md
4.09 KB
Abstract
The incidence of lamellar corneal transplantations is increasing. While a human donor cornea could potentially be used for up to two recipients, one anterior and one posterior part, it does not change the disparity between available donor grafts and patients needing corneal transplants. Additionally, donor grafts carry the risk of graft rejection due to foreign cellular material and disease transmission. We have investigated acellular synthetic graft materials to eliminate these drawbacks using hydrogel materials and the extrusion bioprinting process. To create these materials with higher moduli, the photocrosslinking process has advantages but needs an appropriate crosslinker material. We have shown that we can determine the presence of the non-radicalized crosslinker Lithium Phenyl (2,4,6-Trimethylbenzoyl) Phosphinate (LAP) with spectrophotometric methods, using the crosslinker absorbance characteristics. To show non-radicalized LAP, the measurement is done at 372 nm, and the measured absorbance level depends on the LAP concentration. This allows for a simple evaluation of crosslinked hydrogels to determine any remaining non radicalized LAP and with that potential cytotoxic or other effects of this crosslinking material and correct this situation if necessary.
Dataset DOI: 10.5061/dryad.73n5tb38p
Description of the data and file structure
Polymers were prepared and photocrosslinked with LAP. Optical, mechanical, and chemical testing were performed. All files are Microsoft Excel Worksheets. Samples are denoted as X-Y-Z where X is the methacrylated silk (SilMA) concentration, Y is the methacrylated gelatin (GelMA) concentration, and Z is the LAP crosslinker concentration. The Excel worksheets with "Absorbance" in the title are absorbance data for polymer samples with varying crosslinking times. The number in the title of these sheets is the wavelength. The "Analysis of Crosslinking" worksheet contains data from the plate reader with one sheet with plots. The three worksheets with "TNBS" in the title refer to the TNBS assays used to quantify the degree of methacrylation of the scaffolds. The data are the outputs from the plate reader in the alignment of the plate, with samples labeled. The final worksheet starting with "LAP" also contains outputs from the plate reader which are absorbance values. There is a tab with averages from the runs as well as plots from those averages.
Files and variables
File: LAP_datasets_final.zip
Description: All datasets are saved in the compressed folder 'LAP_datasets.zip.' This folder contains the following files: Absorbance 372 var XL times.csv, Absorbance 450 var XL times.csv, Absorbance 600 var XL times.csv, Absorbance 800 var XL times.csv, Analysis of Crosslinking 120 210 300.csv, Final ABM TNBS_Modified_ABM 022125_MG.csv, Final SilMA TNBS new Assay 102124.csv, Final TNBS_LabGelMA_TNBS_MG022825.csv, LAP_Radicalization_0.25and1_012425.csv. In all files, samples are denoted as X-Y-Z where X is the methacrylated silk (SilMA) concentration, Y is the methacrylated gelatin (GelMA) concentration, and Z is the LAP crosslinker concentration. All data are raw data unless otherwise noted in the document. There is a description of each of these datasets below:
Absorbance Data
Description: These data are derived from plate reader measurements at wavelengths of 372 nm, 450 nm, 600 nm, and 800 nm. The values are unitless measures of absorbance.
Files: Absorbance 372 var XL times.csv, Absorbance 450 var XL times.csv, Absorbance 600 var XL times.csv, Absorbance 800 var XL times.csv
Variables:
- XL time: crosslinking time in seconds (s)
- DI water: deionized water control samples
Files: Analysis of Crosslinking 120 210 300.csv
Variables:
- Wavelength: light wavelength in nm
- DI water tot av: total average of deionized water control samples
- Sample notation: X-Y-Z As (time in seconds) (e.g., SilMa-GelMa-LAP 4-4-0.25 120s)
Files: LAP_Radicalization_0.25and1_012425.csv
Variables:
- Wavelength: light wavelength in nm
- DI water: deionized water control samples
- Sample notation: LAP 0.25% represents 0.25% crosslinker concentration, LAP 1.0% represents 1.0% crosslinker concentration
TNBS Assay Data
Description: These data are derived from plate reader measurements of 96-well plates with samples and reagents used for the TNBS assay. See detailed methods in publication. The values are unitless measures of absorbance. The key for the well plate samples is listed in the sheet (e.g., A123 blank means cells A1, A2, A3 were blank). Concentrations are calculated in the file based on the standard curve. Control groups were Silk_Fibroin and Gelatin (unmodified - not methacrylated).
Files: Final ABM TNBS_Modified_ABM 022125_MG.csv, Final SilMA TNBS new Assay 102124.csv, Final TNBS_LabGelMA_TNBS_MG022825.csv
Variables:
- Abs: absorbance (unitless)
- blank: reaction buffer only plus TNBS reagent
- DS: degree of substitution
- A-H: well plate rows
- 1-12: well plate columns
- Cntrl: control
Code/software
None
Access information
Other publicly accessible locations of the data:
- N/A
Data was derived from the following sources:
- Swindle-Reilly Lab, Chandler Lab, The Ohio State University