Determination of active pharmaceutical ingredients

The strict regulations of the pharmaceutical industry have a significant effect on the quality control of final products, demanding the use of reliable and fast analytical methods. The capacity that the technique has for the simultaneous determination of several APIs with no need of, or with minimum sample pretreatment, has considerably increased its application in pharmaceutical analytical control. The main limitation of NIR is the relative reduced sensitivity that limits the determination of APIs in preparations when its concentration is smaller than 1%. Nevertheless, instrumental improvements allow the determination below this limit depending on the nature of the analyte and the matrix, with comparable errors to the ones obtained with other instrumental techniques. The reference list presents an ample variety of analytical methodologies, types of samples, nature of analyte and calibration models. A detailed treatment of each one eludes to the extension of this chapter. Many applications have been gathered in recent reviews.124-128 Table 10.2 summarizes the most recent reported uses of NIR in this context. 

Springsteen, A. and Ricker, T. (1996) Standards for the measurement of diffuse reflectance. Part I NIR News 7, 6. 

Barnes, P.Y., Early, H.A. and Parr, A.C. (1988) NIST measurement services Spectral reflectance. NIST Special Publication, SP250-48. 

European Pharmacopoeia, 4th Edition (2002) Section 2.2.40 Near infrared spectrophotometry. 

Graham, P., Hailey, P., Hardy, A, Holland, S., Hughes, S., Lee, D., Prebble, K., Salton, N. and Warren, P. (2002) Guidebnes for the development and validation of near-infrared spectroscopic methods in the pharmaceutical industry. In Chalmers, f.M. and Griffiths, P.R. (eds) Handbook of Vibrational Spectroscopy, vol. 5 fohn Wiley Sons Ltd Chichester, UK, pp. 3590-3610. 

---

Kwok, K., Carr, J.E., Webster, G.K., and Carnahan, J.W., (2006) Determination of active pharmaceutical ingredients by heteroatom selective detection using inductively coupled plasma mass spectrometry with ultrasonic nebulization and membrane desolvation sample introduction. j4ppi. Spectrosc., 60, 80-85. 

---