14.1
Introduction
As per the World Health Organization (WHO), the prevalence of skin diseases is
increasing in hot and humid countries like India. The resistant property of the skin
protects the body from several environments such as physical (ultraviolet radiations)
and chemical and microorganisms (Kaur et al. 2020). Global Burden of Disease also
reported that skin disease is leading to be the 18th most common noncommunicable
diseases with around 36.4 million peoples suffered. The major skins diseases are
dermatitis, psoriasis, scabies, fungal skin diseases, acne vulgaris, alopecia areata,
urticaria, keratinocyte carcinoma, etc. (Karimkhani et al. 2017). It is expected that
there will be an increase in the global market for dermaceuticals by 2020, which will
be estimated at around USD 91.40 billion (Kaur et al. 2020). The application of
dermal drug delivery process has also gained particular interest due to its direct
delivery system to the site (skin surfaces), incidences of chronic skin diseases, and
patient compliance. The delivery of the drug into the skin can be broadly classified as
dermal (topically) or transdermal approach (Jain et al. 2017). But it’s a great
challenge for the researchers to overcome the limitations of drug absorption by the
outermost layer of the skin. However, several techniques have been applied to
improve the penetration of the drug into the skin either by disruption or by weaken-
ing the stratum corneum. Techniques such as chemical agents (glycols, ethanol,
terpenes) and physical methods (electroporation, microneedles, microdermabrasion,
and iontophoresis) were used for the successful delivery of the drug into the skin
(Barry 2002; Jain et al. 2015). These two techniques are used lesser due to the
several complications like patient compliances, pain at the site of application, and
skin irritation. So, to overcome these techniques, some formulation-based skin
delivery were nanoparticles, microparticles, and lipid delivery systems. These
formulations can improve the solubilization of drug and can penetrate into the skin
either by sweat gland, transepidermal, or hair follicle (Jain et al. 2015). Among these,
lipid-based nanoformulations (liposomes, solid lipid nanoparticles, nanostructured
lipid carriers) show the capability to challenge the other nanocarriers. These lipid
nanoformulations increase the bioavailability, maintain the physical stability, and
have the controlled release property of the active agents (Puglia and Bonina 2012).
On the other side, these lipid nanoparticles can improve the chemical stability of
the active drugs which are prone to oxidation and hydrolysis or sensitive in the
presence of light (Puglia and Bonina 2012). Scientific evidence related to lipid-based
nanoparticle has revealed that the release rate can be influenced by the type of lipid
used, vehicle, or the concentration of the surfactant used. Other parameters, such as
the method for the preparation of lipid nanoparticles or the concentration of active
drugs in the lipid matrix, also influenced the release rates (Jain et al. 2005). So, the
lipodermal formulations create a lot of opportunities and can minimize the
challenges for the other formulation.
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