{
  "abstract": "Background and Importance Autologous serum eye drops are an alternative treatment for pharmacoresistant dry eye diseases, owing to active molecules such as fibronectin, epidermal growth factor, and vitamin A. Sterility is required but cannot be achieved by autoclaving, as these molecules are heat-sensitive. Sterilising filtration is therefore used although it carries a risk of retaining active molecules within or on the filter, potentially reducing their concentration and efficacy.Aim and Objectives The general aim was to optimise production of autologous serum eye drops by ensuring microbiological safety without altering their properties. The specific objective was to measure vitamin A concentrations under five conditions: no filtration, and filtration through two materials at two porosities each, to evaluate the impact of filtration.Material and Methods Blood samples from five healthy volunteers were collected in trace element–free tubes, allowed to coagulate for 2 hours at room temperature, and centrifuged at 1500 g for 10 minutes at +4°C. The resulting sera were aliquoted under five conditions: no filtration, filtration through polyethersulfone (PES) membranes at 0.22 µm and 0.45 µm, and filtration through cellulose acetate (CA) membranes at 0.22 µm and 0.45 µm, then stored protected from light. Vitamin A concentrations were quantified by high performance liquid chromatography with ultraviolet and bar detector detection. Paired samples were compared using the Wilcoxon signed-rank test, with a significance threshold of p = 0.05.Results In the absence of filtration, the mean vitamin A concentration for the five volunteers was 57 ± 7.3 µg/dL. After filtration, concentrations were: C PES-0.22 = 59 ± 7.0 µg/dL, CPES-0.45 = 59 ± 7.9 µg/dL, CCA-0.22 = 62 ± 8.2 µg/dL, and CCA-0.45 = 62 ± 6.9 µg/dL. Comparisons of filtered vs non-filtered sera yielded p < 0.05, whereas comparisons between materials of identical porosity showed no significant difference (p ≈ 0.06).Conclusion and Relevance For autologous serum eye drops, it is important to ensure that sterilising filtration does not lower active molecule concentrations to levels that could compromise efficacy. For vitamin A, filtration appeared not to affect concentrations. Although not statistically significant, a trend toward differences between PES and CA membranes at identical porosities was observed and will be further investigated in a larger cohort.Conflict of Interest No conflict of interest",
  "authors": [
    {
      "affiliations": [
        "Chu of Limoges, Pharmacy, Limoges, France"
      ],
      "name": "M D’arrigo"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacy, Limoges, France"
      ],
      "name": "M Coulomb"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacy, Limoges, France"
      ],
      "name": "FM Toure"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacology, Limoges, France"
      ],
      "name": "C Barny"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacology, Limoges, France"
      ],
      "name": "A Garnier"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacology, Limoges, France"
      ],
      "name": "N Tafzi"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacology, Limoges, France"
      ],
      "name": "N Picard"
    },
    {
      "affiliations": [
        "Chu of Limoges, Ophthalmology, Limoges, France"
      ],
      "name": "M Rocher"
    },
    {
      "affiliations": [
        "Chu of Limoges, Biochemistry, Limoges, France"
      ],
      "name": "PA Faye"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacology, Limoges, France"
      ],
      "name": "M Labriffe"
    },
    {
      "affiliations": [
        "Chu of Limoges, Pharmacy, Limoges, France"
      ],
      "name": "V Ratsimbazafy"
    }
  ],
  "title": "3PC-007 Impact of sterilising filtration on vitamin A concentration in autologous serum eye drops",
  "uid": "7147080e-079f-5be2-bdd8-1e1a5f90096f"
}