Analysis of Serum Proteins Adsorbed to a Hemodialysis Membrane of Hollowfiber Type by Thermal Lens Microscopy

Abstract

To analyze serum proteins adsorbed to a hemodialysis membrane, immunostaining with colloidal gold and thermal-lens microscopy were employed. A total of 14 types of hemodialysis membranes were tested. The cross sections of the membranes were stained with fluorescent antibodies. Observations of these specimens using a laser microscope revealed that serum proteins, such as albumin and immuno globulins, tended to adsorb into the inner wall of these membranes. The degree of adsorption of serum proteins varied according to various conditions, such as what materials the membranes were made of or what proteins were adsorbed. For a better quantitative analysis of these proteins, the membranes were stained with immunogold and were observed by a thermal lens microscope. Colloidal gold coated with various antihuman serum proteins was used for the staining, and the quantity of colloidal gold was measured with a thermal-lens microscope. The quantity of colloidal gold, coated with anti-human sera antibody, gradiently decreased from the inner to the outer wall of the membrane. Probably, proteins with larger molecules were adsorbed to the inner parts, and those with smaller molecules were adsorbed to the outer parts of the membrane wall. High-resolution thermal-lens microscopy makes possible the sensitive detection of localized proteins adsorbed to a membrane without extracting it. Thus, the analysis of adsorbed proteins should serve to determine the adaptability of medical appliances to the human body and should also be helpful to a retrospective analysis of substances like drugs which are conjugated to the serum proteins.

Peer Reviewed: Thermal Lens Microscopy and Microchip Chemistry

“…perature rise is negligible, it is possible to obtain in vitro, nonlabeled images. TLM imaging has also been demonstrated for measuring tobramycin on a renal tubular cell (12), histamine on a nasal mucous membrane polyp (1), and serum protein in a hollow-fiber membrane (13). One-dimensional scanning of DNA fragments in a miniaturized slab gel has been realized (10,11).…”

Single-Cell Analysis by a Scanning Thermal Lens Microscope with a Microchip: Direct Monitoring of Cytochrome c Distribution during Apoptosis Process

“…In addition, it is known that TLM is not strongly affected by scattering of the laser beam by membranes and particles in cells . We have reported some applications of TLM to imaging of biological samples such as sliced tissues or the outside of a cell membrane using several probing materials. , There are, however, no reports about molecular distribution imaging inside of a cell, nor analysis of intact live cells with TLM.…”

Assay of Spherical Cell Surface Molecules by Thermal Lens Microscopy and Its Application to Blood Cell Substances

“…Immunochemical staining with fluorescence, however, still has some problems, because fluorescence is liable to fade and biomaterials are often inactivated by fluorescence labeling. For more satisfactory quantitative analysis of cell surface substances, we employed immunogold staining and measured the stained cells with a thermal lens microscope. , The principle of thermal lens microscopy is based on the measurement of a laser-induced thermal lens effect, which occurs on the target molecules of the sample under a microscope . Localized molecules, when stained with colloidal gold, absorb the excitation laser.…”