**2. Structural components and their arrangement mechanism**

The core and the shell materials might include different polymeric materials, oils, metal oxides, organic and inorganic compound from the natural and synthetic

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**Figure 1.**

*Schematic diagram of the lipid-polymer hybrid nanoparticles.*

*Lipid Polymer Hybrid Nanoparticles: A Novel Approach for Drug Delivery*

late the hydrophilic or hydrophobic drugs [15].

sources that successfully employed for the fabrication of the NPs. These systems have been composed of following major layers and components given as fellows

ii.The second layer of these hybrid NPs is fabricated with the natural or derived lipid that impart the desired pharmacokinetic properties to the DDS. This layer encapsulates the central polymeric core and enhances the compatibility with the biological system. While it also act as a permeability control barrier that limit the release of loaded therapeutic agent as a function

iii.The third layer is composed of either lipid or polymer-conjugate that help in the functionalization or surface decoration of the NPs to provide the desired therapeutic of pharmacokinetic effects in term of target specific release and

improved retention time of the NPs in the biological system [17].

The mechanism of the arrangement in different layers and their compilation with each other might need further investigation. However, different mechanisms

i.The inner most layer consist of different polymers, organic and inorganic materials that act as a core material. These core materials might be coated with other agents or may form a matrix structure that then functionalized by using the different targeting moieties. These cores of the NPs might encapsu-

*DOI: http://dx.doi.org/10.5772/intechopen.88269*

of water penetration [16].

*Lipid Polymer Hybrid Nanoparticles: A Novel Approach for Drug Delivery DOI: http://dx.doi.org/10.5772/intechopen.88269*

*Role of Novel Drug Delivery Vehicles in Nanobiomedicine*

effective concentration without producing any toxic effects [5].

agents and (4) administration of various theranostic agents [7].

the active therapeutic components and dose related toxicity issues [8, 9].

LPHNPs along with various process parameters and their pros and cons.

**2. Structural components and their arrangement mechanism**

The core and the shell materials might include different polymeric materials, oils, metal oxides, organic and inorganic compound from the natural and synthetic

temperature, and pH [4]. All these factors results in the higher concentration of the entrapped drug that reached the systemic circulation that helps to attain the mean

Among these DDS, polymeric nanoparticles (NPs), liposomes, niosomes, dendrimers and porous silicon NPs have been extensively employed in the pharmaceutical delivery. Polymeric NPs have versatility in term of their chemical composition and applications. Large type of chemical material based NPs were formulated such as polymeric NPs, Porous silicon NPs, Carbon nanotubes, Graphene NPs and quantum dot. All these DDS have their own pros and cons in term of drug loading, encapsulation, release and applicability [6]. Furthermore, all these DDS were decorated with different chemical reagents and ligands to impart the desired characteristics through modifying the physicochemical properties of the NPs including (1) enhanced means residence time and improved stability, (2) external stimuli driven drug release, (3) controlled and targeted delivery of various chemotherapeutics

These nanocarriers have been explored due to their extensive potential applications and excellent in vitro performances, but these NPs still have poor in vivo properties in term of their poor solubility in various body fluids, rapid uptake and excretion by the body defense system, poor penetration among the various biological membranes and body tissues, uncontrolled fluctuations in the plasma levels of

The most important domains of these nanocarriers include the polymeric DDS and the lipid based vesicular systems. The polymeric DDS provide the variety in term of their structural materials and chemical composition [6]. Different polymers include from the synthetic and natural sources have been employed for the medical applications. These DDS include the polymeric NPs, mesoporous silicon NPs, metal coated NPs, inorganic NPs, dendrimers and the carbon nanotubes [10]. Vesicular DDS include the liposome and noisome. These were defined as the single and the multilayer lipid vesicles while the niosomes were made up of nonionic surfactants instead of the phospholipids [11]. These novel systems provide excellent compatibility with other ingredients, higher and simultaneous encapsulation of the hydrophilic and lyophilic therapeutic moieties and due to lipid nature it provide better pharmacokinetic profiles that might lead to improved therapeutic response of the encapsulated drug. But still this system might suffer from some draw back in term of drug leakage, stability problems and difficulty in the scale up of the process [12]. The above-mentioned problems associated with these DDS including liposomes and polymeric nanoparticles can be overcome by merging their structural components by formulating the lipid-polymer hybrid nanoparticles (LPHNPs). These NPs combine the potential benefits and reduce the different drawbacks of all the individual structural components [13]. These hybrid particles might be produced in different morphologies including the core shell and matrix type LPHNPs. The core or the central material may be encapsulated in single and/or multiple layers of the lipid on the polymeric core materials that also provide the site for the surface modification with different targeting moieties and ligands that help to induce the desired characteristics in the DDS [14]. In this chapter, the different structural components such as lipids and polymers were explained along with the different formulation methods to prepare the

**60**

sources that successfully employed for the fabrication of the NPs. These systems have been composed of following major layers and components given as fellows


The mechanism of the arrangement in different layers and their compilation with each other might need further investigation. However, different mechanisms

**Figure 1.** *Schematic diagram of the lipid-polymer hybrid nanoparticles.*

explored indicate that the arrangement and fusion process are based on the method of preparation (that were discussed in the next section). In the two-step conventional method, the layer might be due to formation of lipid by layer that get adhere to the core particle that followed by the integration due to hydrophilic and hydrophobic interaction among the lipid and polymer component. However, in the single-step method, the most investigated and revealed mechanism is the precipitation of the lipid component on the polymeric core material. Some newer techniques might also involve the self-assembling of these structural components (**Figure 1**) [18].
