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Review
. 2021 Dec 31;14(1):90.
doi: 10.3390/pharmaceutics14010090.

Lipid Nanoparticles for the Posterior Eye Segment

Lorena Bonilla  1   2 , Marta Espina  1   2 , Patricia Severino  3 , Amanda Cano  1   2   4 , Miren Ettcheto  4   5 , Antoni Camins  4   5 , Maria Luisa García  1   2   5 , Eliana B Souto  6 , Elena Sánchez-López  1   2   4
Affiliations
Review

Lipid Nanoparticles for the Posterior Eye Segment

Lorena Bonilla et al. Pharmaceutics. .

Abstract

This review highlights the application of lipid nanoparticles (Solid Lipid Nanoparticles, Nanostructured Lipid Carriers, or Lipid Drug Conjugates) as effective drug carriers for pathologies affecting the posterior ocular segment. Eye anatomy and the most relevant diseases affecting the posterior segment will be summarized. Moreover, preparation methods and different types and subtypes of lipid nanoparticles will also be reviewed. Lipid nanoparticles used as carriers to deliver drugs to the posterior eye segment as well as their administration routes, pharmaceutical forms and ocular distribution will be discussed emphasizing the different targeting strategies most recently employed for ocular drug delivery.

Keywords: NLC; SLN; drug transport; lipid nanoparticles; ocular barriers; ocular drug delivery; posterior segment.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Barriers to ocular drug penetration: (a) the tear film is composed of three layers, the lipid layer, the aqueous layer and the mucin layer; (b) the corneal layer is formed by epithelium, Bowman’s membrane, stroma, Descemet’s membrane and endothelium; (c) the conjunctival barrier is vascularized; (d) the blood–aqueous barrier starts on the stroma of ciliary body and is composed by the basement membrane, pigmented cells, nonpigmented cells and delimited by the basement membrane; (e) the blood–retinal barrier is formed by the retinal ganglion cells, amacrine cells, bipolar cells, horizontal cells, both types of photoreceptors, retinal pigment epithelium (RPE) and the Bowman’s membrane. Adapted from [3,14,15], Sánchez-López, E., 2017; Farid, R.M., 2017; and Keeling, E., 2018.
Figure 2
Figure 2
Anatomy of the posterior segment of the eye. Adapted from [24,25] Akbar, S., 2017 and Bharali, P., 2015.
Figure 3
Figure 3
Representation of the different delivery routes for ocular administration [31,32]. Next to each administration, needle and injection technique are summarized. Adapted from [23,33,34,35,36,37,38,39], Varela-Fernandez, R., 2020; Doshi, R., 2011; Moshfeghi, D.M., 2002; Yïu, G., 2020; El Raves, E.N., 2013; Do, J.L., 2020; Pakravan, M., 2017; Davis, J.L., 2019.
Figure 4
Figure 4
Three models of SLN drug incorporation: (a) homogeneous matrix model, (b) drug-enriched shell model, (c) drug enriched core model. Red color indicates the active compound encapsulated, yellow and grey color refer to lipid phases with and without dispersed drug, respectively. Adapted from [63], Müller, R. H., 2000.
Figure 5
Figure 5
Representation of the drug expulsion during storage of SLNs and three types of NLC: type-I structurally different lipids, type-II amorphous lipids and type-III liquid lipid included in solid matrix. Red color indicates the active compound. Adapted from [68,69], Müller, R.H., 2002; Narvekar, M., 2014.
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References

    1. Keeffe J., Resnikoff S. Innovative Approaches in the Delivery of Primary and Secondary Eye Care. Springer; Berlin/Heidelberg, Germany: 2019. Prevalence and Causes of Vision Impairment and Blindness: The Global Burden of Disease; pp. 7–20.
    1. Thareja A., Hughes H., Alvarez-lorenzo C., Hakkarainen J.J., Ahmed Z. Penetration Enhancers for Topical Drug Delivery to the Ocular Posterior Segment—A Systematic Review. Pharmaceutics. 2021;13:276. doi: 10.3390/pharmaceutics13020276. - DOI - PMC - PubMed
    1. Sánchez-López E., Espina M., Doktorovova S., Souto E.B., García M.L. Lipid nanoparticles (SLN, NLC): Overcoming the anatomical and physiological barriers of the eye—Part I—Barriers and determining factors in ocular delivery. Eur. J. Pharm. Biopharm. 2017;110:70–75. doi: 10.1016/j.ejpb.2016.10.009. - DOI - PubMed
    1. Alvarez-Trabado J., Diebold Y., Sanchez A. Designing lipid nanoparticles for topical ocular drug delivery. Int. J. Pharm. 2017;532:204–217. doi: 10.1016/j.ijpharm.2017.09.017. - DOI - PubMed
    1. Pramanik S., Mohanto S., Manne R., Rajendran R.R., Deepak A., Edapully S.J., Patil T., Katari O. Nanoparticle-Based Drug Delivery System: The Magic Bullet for the Treatment of Chronic Pulmonary Diseases. Mol. Pharm. 2021;18:3671–3718. doi: 10.1021/acs.molpharmaceut.1c00491. - DOI - PubMed

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