Section 3 Nano Biomaterials

**75**

**Chapter 5**

*Luis Castañeda*

**Abstract**

pharmacokinetic

**1. Introduction**

ability and permeability [4].

A Facile Method for Formulation

Enhanced Bioavailability

of Atenolol Nanocrystal Drug with

Atenolol is a commonly used antihypertensive drug of class III BCS category. The objective of the present study is to enhance the permeability of atenolol by using a suitable technique which is economical and devoid of using any organic solvents. The nanocrystal technology by high pressure homogenization was chosen for this purpose, which is less expensive and simple method. In this technique, no organic solvent was used. The study was further aimed to characterize prepared nanocrystals in solid state by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD) patterns, particle size, zeta potential, % yield, and drug permeation study through isolated goat's intestine. An in vivo study was carried out to determine the pharmacokinetic property in comparison to pure drug powder using rats as experimental animals. The formulation design was optimized by a 3(2) factorial design. In these designs, two factors, namely surfactant amount (X1) and speed of homogenizer (X2), were evaluated on three dependent variables,

namely particle size (Y1), zeta potential (Y2), and production yield (Y3).

**Keywords:** atenolol, nanocrystal, factorial design, ANOVA, antihypertensive,

A nanocrystal is a particle having one or more dimensions of the order of 200 nm or less and considered to have novel characteristics which differentiate them from other materials [1]. When the size of the material is reduced to less than 200 nanometers, the realm of quantum physics takes over and five materials begin to demonstrate entirely new properties. Hence, nanodesign of drugs by various different techniques, like melting, homogenization, and controlled precipitation, is explored to produce drug nanocrystals, nanoparticles, nanosuspensions, etc. [2]. As decrease in size will increase the solubility of drugs, this technology is explored to increase oral bioavailability of sparingly water soluble drugs [3]. Development of soluble and/or permeable drug molecules using nanocrystal formulations has been proven to be successful due to their unique size range and higher surface: volume ratio, which results in enhanced drug dissolution, bioavail-

Atenolol is a selective *β*1 receptor antagonist, a drug belonging to the group of beta blockers, which is used mainly in different cardiovascular diseases [5]. It often
