**7. NMR analyses**

Nuclear magnetic resonance (NMR) is a powerful analytical tool for identification and quantification of capsaicinoids in raw materials for pepper spray solutions. Its ability to analyze samples with minimum pre-treatment allows a safe analysis that preserves the original characteristics. In the specific case of organic molecules, their sensitivity is increased by the detection of the isotope 1 H. Thus, the ability of NMR to evaluate the quality control of the nonlethal arms industry becomes clear.

In order to verify the N.Cap content, a sample of 26.4 mg was weighed and solubilized in 600 μl of CDCl3 in a 5-mm NMR tube. The analysis was performed at 25°C using glass capillary for the quantification of the maleic acid present in the solution with 100 mmol of D2O. The broad band inverse (BBI) probe inserted into Bruker Avance III 11.75 T equipment was used. The simple pulse sequence used was zg. The spectra were processed with 0.3 Hz line broadening and zero filling.

**Figure 2** shows the graphical results, and the relative chemical shift integration of hydrogens of capsaicin and dihydrocapsaicin are presented. All the signals of the main chemical groups present in the sample were identified through the NMR analyses. Groups 1 from capsaicin and 2 from dihydrocapsaicin (amplified in **Figure 2**) can be used for relative integration of the signals. In addition to being unobstructed, they had a higher signal-to-noise ratio due to having six hydrogens contributing to the integration of each signal. Thus, it was possible to verify the proportion of these compounds among themselves present in the mixture. This led to the proportion of 33% dihydrocapsaicin (minority) and 66% capsaicin (majority), the latter being twice the concentration of the former.

The 1 H NMR technique proved efficient in the identification and relative quantification of the components present in the mixture of pepper derivatives. The spectra were acquired quickly and with a simple sample preparation step.

**167**

**8. Conclusion**

**Figure 2.** *<sup>1</sup>*

product. The 1

*Use of Capsaicin for Nonlethal Technology DOI: http://dx.doi.org/10.5772/intechopen.92357*

The analyses allowed a broad view of the absence of other compounds, even if minority, thereby proving the purity of the material and absence of degradation products. On the other hand, the presence of other components could be identified concomitantly in a mixture of higher complexity. Thus, this work suggests that 1

The main aspects of pepper spraying technology were discussed and the main concepts related to use, hazardous, solution formulations and quantification tests were pointed out. This technology is relatively recent, and a wide field of research is not addressed yet. The advance showed here is around the use of capsaicinoids to extract raw material N.Cap instead of OC to produce pepper spray. The absence of oils and resin is the main point, as nonflammability is achieved much more easily and without the use of hazardous organic solvents. Chemical analyses by GC-MS/ FID applied to quantify capsaicinoids (capsaicin and dihydrocapsaicin together) have been demonstrated and can be reproducible for the quality control of this

H NMR provides information about raw material and how to access

NMR can be used as a quality control tool in the nonlethal industry.

*H NMR identification and relative quantification of the components present in the N.Cap.*

quality information and impurity with our relative concentration.

voluntaries is the way for a better evaluation of limits.

The concentration range between 0.2 and 0.3% (mass of solution) of capsaicinoids guarantees satisfactory spray efficiency, allowing the aggressor to be incapacitated without serious injury. Toxicological study preferred with human

H

Capsicum

coefficient R<sup>2</sup>

**Figure 1.**

spray solution.

**7. NMR analyses**

standard solutions made with Sigma-Aldrich Capsaicin (purity capsaicin: 61.1%, dihydrocapsaicin: 31.2% LOT#: LRAA9221 09 September 2015). The regression

*GC-FID chromatogram of capsaicin and dihydrocapsaicin peaks with retention time around 24 min.*

satisfactory by the statistical linear fit results. In this way, it is possible to quantify the capsaicinoids, that is, capsaicin and dihydrocapsaicin together, on the pepper

Nuclear magnetic resonance (NMR) is a powerful analytical tool for identification and quantification of capsaicinoids in raw materials for pepper spray solutions. Its ability to analyze samples with minimum pre-treatment allows a safe analysis that preserves the original characteristics. In the specific case of organic molecules,

NMR to evaluate the quality control of the nonlethal arms industry becomes clear. In order to verify the N.Cap content, a sample of 26.4 mg was weighed and solubilized in 600 μl of CDCl3 in a 5-mm NMR tube. The analysis was performed at 25°C using glass capillary for the quantification of the maleic acid present in the solution with 100 mmol of D2O. The broad band inverse (BBI) probe inserted into Bruker Avance III 11.75 T equipment was used. The simple pulse sequence used was

zg. The spectra were processed with 0.3 Hz line broadening and zero filling.

**Figure 2** shows the graphical results, and the relative chemical shift integration of hydrogens of capsaicin and dihydrocapsaicin are presented. All the signals of the main chemical groups present in the sample were identified through the NMR analyses. Groups 1 from capsaicin and 2 from dihydrocapsaicin (amplified in **Figure 2**) can be used for relative integration of the signals. In addition to being unobstructed, they had a higher signal-to-noise ratio due to having six hydrogens contributing to the integration of each signal. Thus, it was possible to verify the proportion of these compounds among themselves present in the mixture. This led to the proportion of 33% dihydrocapsaicin (minority) and 66% capsaicin (majority), the latter being

H NMR technique proved efficient in the identification and relative quantification of the components present in the mixture of pepper derivatives. The

spectra were acquired quickly and with a simple sample preparation step.

H. Thus, the ability of

their sensitivity is increased by the detection of the isotope 1

twice the concentration of the former.

was 0.999 and uncertainty was 0.9%. The subsequent dilution was

**166**

The 1

**Figure 2.** *<sup>1</sup> H NMR identification and relative quantification of the components present in the N.Cap.*

The analyses allowed a broad view of the absence of other compounds, even if minority, thereby proving the purity of the material and absence of degradation products. On the other hand, the presence of other components could be identified concomitantly in a mixture of higher complexity. Thus, this work suggests that 1 H NMR can be used as a quality control tool in the nonlethal industry.
