Current HPLC Methods for Assay of Nano Drug Delivery Systems

Abstract

In nano drug formulations the mechanism of release is a critical process to recognize controlled and targeted drug delivery systems. In order to gain high bioavailability and specificity from the drug to reach its therapeutic goal, the active substance must be loaded into the nanoparticles efficiently. Therefore, the amount in biological fluids or tissues and the remaining amount in nano carriers are very important parameters to understand the potential of the nano drug delivery systems. For this aim, suitable and validated quantitation methods are required to determine released drug concentrations from nano pharmaceutical formulations. HPLC (High Performance Liquid Chromatography) is one of the most common techniques used for determination of released drug content out of nano drug formulations, in different physical conditions, over different periods of time. Since there are many types of HPLC methods depending on detector and column types, it is a challenge for the researchers to choose a suitable method that is simple, fast and validated HPLC techniques for their nano drug delivery systems. This review's goal is to compare HPLC methods that are currently used in different nano drug delivery systems in order to provide detailed and useful information for researchers.

Organic and Biogenic Nanocarriers as Bio-Friendly Systems for Bioactive Compounds’ Delivery: State-of-the Art and Challenges

“…(ii) Spectroscopic techniques: Ultra-violet visible (UV-Vis) absorption spectroscopy, Fouriertransform infrared spectroscopy (FTIR), fluorescence spectroscopy, dynamic light scattering [DLS, also known as photon correlation spectroscopy (PCS) or quasi-elastic light scattering (QELS)], laser diffraction (LD), zeta potential (ζ), X-ray diffraction (XRD), energy dispersive X-Ray spectrometry (EDS), small-angle X-Ray scattering (SAXS), small-angle neutron scattering (SANS), inductively coupled plasma-optical emission spectrometry (ICP-OES) which offer relevant insight on several physicochemical properties such as the identification of spectral signatures of the components belonging to nanocarriers, understanding the interaction between components (bioactive compounds, matrix, etc.) of nano-DDS and between entire nano-DDS and the environment, particle size and particle size distribution, polydispersity index, particle charge, aggregation state, physical stability, structural organization and structural changes, degree of crystallinity, and elemental composition; (iii) Separation techniques: High-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS), used to separate, identify, and quantify various components, and also for the determination of the released drug content out of nano drug delivery systems, over time, in different physical conditions [294]; (iv) Biochemical and biological techniques: Offer relevant insight on antioxidant activity: the evaluation of the ability to scavenge short-life (by chemiluminescence technique) and long-life [by DPPH (2,2-diphenyl-1-picrylhydrazyl), and ABTS •+ (2,2-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) method] free radicals; ferric reducing antioxidant power (FRAP), and ferrous ions (Fe 2+ ) chelating activity (FIC) assays}, antimicrobial activity [agar well diffusion method; minimum inhibitory concentration (MIC) determination], cytotoxicity tests [using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction assay], hemocompatibility evaluation [295,296]; (v) Other techniques: for example: thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), provides information about thermal stability, purity, homogeneity, phase transitions of the sample, and the crystalline nature of the nanostructure [260].…”

Adipocyte-Based Cell Therapy in Oncology: The Role of Cancer-Associated Adipocytes and Their Reinterpretation as Delivery Platforms

“…Then, through comparative analysis, which involves the evaluation of growth media composition at incipient and final steps, the amount of drug included in the cell is determined. Concerning the drug encapsulation and release parameters, chromatography is one of the most employed techniques, particularly high-performance liquid chromatography (HPLC) [184].…”