Tear film proteins deposited on high water content contact lenses identified with two‐dimensional gel electrophoresis and mass spectrometry

Abstract

ABSTRACT.Purpose: Tear film proteins adhere to the surface of contact lenses (CLs). While the proteins in the tears have been extensively studied with various proteomic techniques, adhered proteins to CLs are less studied. In this pilot study, we have separated proteins with 2D gel electrophoresis prior to the conventional mass spectrometry (MS) in order to analyse the deposited proteins on hydrogel CLs from myopic patients. Methods: pHEMA and PVA hydrogel CLs worn by 3 patients for different time lengths were analysed. After wear, the CLs were frozen at À20°C. Proteins were extracted in lysis buffer, separated on 12% polyacrylamide gels and silverstained. Protein spots were excised and identified with liquid chromatographytandem MS. Results: Deposited proteins were extracted with a yield of 26-66 lg and separated by 2D gel electrophoresis. The silver-stained gels showed similar protein patterns independent of the patient, hydrogel type and wear time. Seventy-two spots were analysed with MS, representing at least 12 different tear film proteins or protein fragments. Conclusions: Deposited tear film proteins from a single set of CLs worn for 1 day can successfully be analysed first with 2D gel electrophoresis and subsequently with MS, thus making examination of individual patients possible. The protein composition appeared homogeneous between the test persons which is a necessity for additional comparison analysis. The molecular masses of the identified proteins indicate that protein degradation occurs only as a minor event. Myopic patients were investigated in this pilot study, but the combined techniques can easily be applied to other eye diseases.

Functional Hydrogels and Their Application in Drug Delivery, Biosensors, and Tissue Engineering

“…In the biomedical field, hydrogels are a new class of functional polymer materials with enormous potential in biotechnology. When the polymer network is encased in water, the material absorbs the water and adopts fluidic properties, which is very similar to what occurs with tissues in the human body [4,5]. In the presence of water, the surfaces of the hydrogels become wet and malleable.…”

“…Similarly, Devadhasan and Kim introduced a new method to quantify various pH solutions with a complementary metal oxide semiconductor image sensor, which produced high-accuracy analyses based on pH measurement [123]. In this approach, a thin film was fabricated by merging a pH indicator with the hydrogel matrix and the modified gel exhibited color change development across the full spectrum of pH (pH [1][2][3][4][5][6][7][8][9][10][11][12][13][14].The complementary metal oxide semiconductor image sensor then absorbed the color intensity of the hydrogel film, and the hue value was converted into digital data with the help of an analog-to-digital converter to determine the pH ranges of solutions [123]. This gel may be useful for in situ pH sensing in the presence of toxic chemicals and chemical vapors.…”