Biodegradable Nanoparticles for Drug Delivery

Among other approaches tried by scientists, colloidal systems like liposomes, polymeric nanoparticles etc., have shown promise but not many products have made it to the market (7). Nanoparticulate drug delivery systems are gaining much popularity in recent years. Among these, nanoparticulate drug delivery systems from biodegradable and biocompatible polymer are an interesting option for controlled drug delivery and drug targeting (8). Amongst the various drug-delivery systems, solid lipid nanoparticle (SLN) and nanostructured lipid carrier (NLCs) are potentially attractive choices due to their natural components and easily scaled-up formulation processes. In addition, their hydrophobic core provides a suitable environment for entrapment of hydrophobic drugs (9). Among the important technological advantages of nanoparticles as drug carriers are: high stability (i.e. long shelf life), high carrier capacity (i.e. many drug molecules can be incorporated into the particle matrix), feasibility of incorporation of both hydrophilic and hydrophobic substances, and feasibility of variable routes of administration (10). NLCs are kind of lipid-based nanoparticles, which has the advantages of biodegradable, brain targeting, well-recognized safety profile by drastically reducing drug-related toxicities through reduction of nonspecific biodistribution (11). NLCs consist of an unstructured solid lipid

Many molecules, particularly peptides and polypeptides are physically embedded in polymers to create a complex network of interconnecting pores through which the drug could subsequently diffuse. The pore structure and polymer composition is controlled in order to design systems that release the drug at nearly any rate and for nearly

Nanocarriers (NCs) have emerged as a favored drug delivery approach towards improving the anticancer benefits of several bioactives for cancer therapy with recent reports showing the application of NC systems in clinical settings [18]. The NCs with size < 100 nm have been associated with enhanced permeation and retention effect (EPR) due to the presence of leaky vasculature in the tumor tissues which contributes to its enhanced efficacy. Also recently, NCs have shown to be effective in the treatment of malignant mesothelioma [19]. A recent study by Kanai et al. showed that the NC albumin-bound paclitaxel and carboplatin (nabPC) repetitively achieved tumor regression in malignant mesothelioma

Another possibility is the process of disguising medically active molecules with lipophilic molecules that allow it to better sneak through the bbb, this is known as the pro-drug method. Another idea similar to the pro-drug method is peptide masking which masks the drugs chemical composition by masking a peptide's (a compound consisting of two or more amino acids linked in a chain) Characteristics by combining with other molecular groups that are more likely to pass through the bbb. An example of this is using a cholesteryl molecule instead of cholesterol that serves to conceal the water soluble characteristics of the drug. One of the most promising drug delivery systems is using nanoparticle delivery systems. These are systems where the drug is bound to a nanoparticle capable of traversing the bbb. The most promising compound for the nanoparticles is Human Serum Albumin (the most abundant protein in human blood plasma). The main benefits of this are that particles made of HSA are well tolerated and do not have any serious sided

Example-2: Nelfinavir-PLGA NPs were prepared by nanoprecipitation method. Drug:polymer weight ratio was varied from 1:1 to 1:5 and particle size, encapsulation efficiency and drug loading were measured. Among the drug:polymer weight ratios prepared, 1:4 ratio was chosen as optimal. NPs found to exhibit sustained drug release up to 24 h and there was a 4.94-fold increase in relative bioavailability compared to pure drug (Venkatesh et al. 2015).

Therefore the systemic delivery of protein or peptide biologics requires the parental route of administration through subcutaneous injections, but there are multiple problems with this method of drug delivery. For systemic absorption, intact drug molecules must pass from the administration site through or between the intestinal epithelial cells to the general circulation and the target site (Lee et al.,

Pharmacokinetic analysis suggests that the orally administered nanoemulsions had a higher rate of absorption and the concentration of the drug in the brain and plasma was the highest. Formulation: The drug nanoemulsion was prepared by adding 50% of the drug solution (with dehydrated ethanol) to one ml of safflower oil and it was stirred for the oil drug mixture to distribute homogenously and for all the ethanol to evaporate. Deionized distilled water (contains egg phosphatidylcholine) and deoxycholic acid.(40mg) make up the aqueous phase. Both the phases are heated at 70oc separately. The oil phase was slowly added to the aqueous phase and stirred well. The mixture was then sonicated (21% amplitude and 50%duty cycle). The mixture formed (drug containing nanoemulsion) was then filtered and stored at 4oc.Preparation of aqueous suspension was made using 3H Labeled drug and unlabeled drug in ethanol along with Deionized distilled water (contains egg phosphatidylcholine) and deoxycholic acid. The suspension was sonicated in order to lessen the particle size [2]. An example is Saquinavir (anti-HIV inhibitor) showed enhanced oral absorption and increased concentration of drug in the brain when incorporated in a nanoemulsion

This technique relies on a simple liquid phase extraction technique followed by positive electrospray ionization-tandem mass spectrometry detection without involvement of any chromatographic method for quantification of docetaxel in biological matrices. Quantification of drug in biological matrices is necessary to establish pharmacokinetic parameters. The analytical method developed and validated here was further used to determine pharmacokinetic characteristics and biodistribution profile of docetaxel injected to mice in the form of polymeric nanoparticles prepared and characterized in our

It was proven that surface active agents which are the backbone of the formulated lipid vesicles can enhance the transdermal delivery of drugs by lowering the permeability barrier of the skin and interacting with the SC in vitro [45]. On the other hand, Studies also reported that the drug molecules to be effectively transported across the SC they must be entrapped within the lipid vesicles suggesting that the vesicles act as drug carrier systems and not as penetration enhancers [46].

Nanoparticles have a series of advantages, such as relatively high drug loading, stability in the body fluids and storage conditions, slow controlled release and targeting effect, and easily industrialized production,and they have thereforebecome the hot spot of brain targeted research [14, 15]. Nanoparticles could carry drugs through the BBB and act in the CNS; especially after surface modification they can avoidphagocytosis by thereticuloendothelial system to make drugs available through the BBB and significantly improve the concentration of drugs in the brain, which is becoming an important research field of the basic researchand application of drug delivery

theranostic approaches combining molecular imaging and in situ drug delivery. Targeting the cellular and molecular components that

So, the combination of ultrasound and transfection agents and Gene encapsulated in the agents could be a promising way to enhance gene delivery and transfection efficient significantly.

Existing gene delivery systems can be broadly classified into two categories: viral and non-viral. The first gene delivery systems were viral. Viruses were the first choice for vectors in early studies of gene therapy because they have evolved to effectively transfer DNA into target cells. To produce viral vectors, the sections of the virus's genome that enable it to replicate are removed and replaced with the therapeutic gene sequence. The result is an attenuated virus capable of efficiently transferring the therapeutic gene sequence but incapable of replicating in vivo. Disadvantages of viral vectors include limited DNA-carrying capacity, restricted cell targeting, and immunogenicity. Non-viral gene delivery systems seem to be a promising alternative. Non-viral vectors consist of naked DNA in the form of plasmids (circular pieces of DNA) or oligonucleotides (short, single-stranded pieces of DNA) and complexed – “packaged” – DNA, typically with cationic (positively charged) lipids or polymers. In general, naked DNA is safer but significantly less efficient than viral vectors. Barriers to efficient non-viral gene delivery include DNA degradation, lack of cell targeting, and limited cell uptake of DNA. However, the complexation of naked DNA facilitates the process since cationic lipids and polymers protect the DNA and facilitate transport. Current research efforts primarily focus on the development of more efficient non-viral gene

Cancer claims more than half a million lives in the United States every year (National Cancer Institute). Cancer is commonly perceived to be a fatal illness that leads to a slow death. Many cancer patients have little or no hope when they are diagnosed with this devastating disease. However, there is a new breakthrough in combating cancer. This new strategy has brought renewed hope to millions of patients. Nanotechnology is the newest weapon in the war waged against cancer. Nanotechnology is defined by the National Nanotechnology Initiative as “research and technology development at the atomic, molecular, or macromolecular scale leading to the controlled creation and use of structures, devices, and systems with a length scale of approximately 100 nm”. Nanotechnology presents the potential to be extremely effective in aiding cancer research and treatment. The implementation of nanoparticles is a major development in the field of medicine, and its involvement in the fight against cancer has yielded positive results. Nanotechnology allows for precise targeting of malignant cells, which was a challenge in the past. Some complications remain, but these few can be eliminated through more research. Overall, nanotechnology presents a more safer and practical approach to eradicate tumors. The approach for eliminating cancer in the U.S. should not be surgery, chemotherapy, or radiation therapy; instead, the use of nanotechnology to combat cancer

Nanotechnology is a recently developed technique to produce nanoparticles. According to the definition from British Standards Institution, nanotechnology refers to the intentional design, characterization, production and applications of materials, structures, devices and systems by controlling their size and shape in the nanoscale range1. Nanotechnology covers versatile applications, such as medicine. Nanomedicine is defined as the field of medicine that aims to use the properties and physical characteristics of nanomaterials at the molecular level2. In general, nanomedicine exhibits tremendous advantages over conventional medicine. Therefore, it is widely applied for various purposes, for instances, diagnosis, prevention and treatment