Current Pharmaceutical Analysis, 2009, 5, 69-88 69 1573-4129/09 $55.00+.00 © 2009 Bentham Science Publishers Ltd. Electrochemical, Spectrophotometric and Liquid-Chromatographic Ap- proaches for Analysis of Tropical Disease Drugs André L. Santos 1,* , Regina M. Takeuchi 2 and Nelson R. Stradiotto 2 1 Faculdades de Ciências Integradas do Pontal, Universidade Federal de Uberlândia, 38302-000, Ituiutaba, MG, Brazil 2 Universidade Estadual Paulista (UNESP), 14801-970, Araraquara, SP, Brazil Abstract: Drug analysis is important in several phases of drug development, such as formulation, stability studies and quality control. The importance of reliable analytical methods for drug determination in a fast, inexpensive, sensitive and selective way is thus evident. Although there are countless works describing new analytical methods for determination of drugs that act against tropical diseases, a review organizing these works in a systematic and complete way is lacking. In this context, the objective of this review is to present the main advances in the development of analytical methods for de- termination of tropical disease drugs using electroanalytical, spectrophotometric and liquid chromatographic techniques. Keywords: Tropical diseases, Analytical methods, Drug analysis, Electroanalytical, Spectrophotometry, Chromatography. 1. TROPICAL DISEASES Tropical diseases include some infectious/parasitic dis- eases whose incidence depends on geographic/climatic and/or socioeconomic conditions. They are endemic in tropi- cal and subtropical regions, affecting countries in Asia, Af- rica, South America and Oceania, mainly. Historically, these diseases have been overlooked by the pharmaceutical indus- try, assistance programs, and medical and scientific commu- nities worldwide. For this reason, they are often referred to as “neglected tropical diseases”. A less common designation for these diseases is “biblical diseases” because they have afflicted humanity since time immemorial and have a long history of stigma and poverty [1, 2]. Tropical diseases include different kinds of parasites, such as worms and protozoa, living in aquatic environments or in the soil. They are a symptom of the poverty and socio- economic underdevelopment affecting the poorest countries, where the establishment of marginal communities living with precarious sanitation infrastructure and no access to safe water sources is common [1]. These diseases can cause se- vere and permanent disabilities and/or deformities, but they rarely lead to death. Because of their low mortality, these illnesses have remained a low priority. However, the price paid for neglecting them is too high. According to the WHO, approximately 1 billion people (one sixth of the world’s population) suffer from one or more neglected tropical dis- eases [1]. Despite this impressive data, less than 1 % of the new drugs registered between 1975 and 1999 were designed for the treatment of these diseases [1]. Their impact on the quality of life can be estimated from their correlation with impaired child growth and development, complications dur- *Address correspondence to this author at the Faculdades de Ciências Inte- gradas do Pontal, Universidade Federal de Uberlândia, 38302-000, Ituiu- taba, MG, Brazil; Tel: +55-34-3269-2389; Fax: +55-34-3269-2389; E-mail: alsantos@pontal.ufu.br ing pregnancy, underweight babies, significant and some- times disabling disfigurements, blindness, social stigma, and reduced economic productivity and household incomes [1,3]. Despite the drastic impact of tropical diseases on mar- ginalized communities, population-wide interventions, such as vector control and mass drug administration, are powerful enough to interrupt transmission in several cases [1]. How- ever, to eradicate or at least keep the incidence of tropical diseases at an acceptable level, an effective partnership be- tween the scientific and medical communities, population, pharmaceutical industry, public administration sectors and policy-makers is necessary, as discussed by Sachs and Hotez [4]. An integrated action focused not only on the treatment of infected individuals but also on the improvement of the so- cioeconomic aspects and sanitary infrastructure of marginal- ized communities seems to be the only way to avoid deaths and losses of work power due to tropical diseases. It is clear that this means a big challenge for the world society. The control of tropical illnesses is indeed feasible and some re- cent initiatives involving different sectors of society have aimed at launching a more integrated assault against them [5, 6]. Fortunately, there are safe, effective and low-cost tech- nologies available for the immediate and isolated treatment of most of the tropical diseases, mainly those regarding the use of chemotherapeutic agents. For example, praziquantel is very effective for the treatment of schistosomiasis, while albendazole has been successfully employed for soil- transmitted helminthiasis [1]. Similarly, there are safe and effective drugs available for most of the tropical diseases at low-cost. A complete list including all the tropical diseases and their respective drugs is beyond the scope of this work; however; a list containing the most important/common tropi- cal diseases and the drugs used for their treatment is pre- sented in Table 1. More complete lists and information about the chemotherapy of tropical diseases can be found in refer-