Introduction

Fingerprints are the tiny ridges formed during the embryological development of the volar pads of the fingers [1]. Over time, despite researchers’ concerns about the uniqueness of fingerprints, they are still a prominent and popular method to distinguish individuals from one another [2]. Fingerprints are defined as the evidence of fingermarks, whether deliberately taken, stamped with ink, or marks left on objects because they have been touched by the skin of the palms [3]. Simultaneously, the permanent nature of the fingerprints makes them valuable evidence against the criminals at crime scenes [4]. It has been more than a century that fingerprints have been used to document crime investigations all over the globe [5].

Although, over time, various new techniques are developed to detect the latent fingerprint, the powder method is the simplest technique applied to identify the latent fingerprints [6]. When the powder is sprinkled on the impacted area of the fingerprints, it sticks to sweat, oil, or other materials left in the fingerprint. The powder technique to visualize the fingerprints has been used since the early 1900s [7]. So far, hundreds of fingerprint powder formulas have been created, with each formula comprising a dye for coloration, contrast, and a resin material for good adhesion [8]. Besides, concerning the health hazard linked with the conventional fingerprint powders, researchers highlighted the importance of non-toxic and easily available fingerprint powders [9].

Since heavy metal toxicity affects individuals’ health, mercury and lead-based powder formation to detect fingerprints is the least preferred nowadays and has almost become obsolete [1]. Even researchers reported the most commonly used fingerprint powders, i.e. carbon black powder and cyanoacrylate fumes, as dangerous for health [10]. Souter, Van Netten, and Brands [11] reported that police officers directly exposed to fingerprint powders suffer serious visual and skin disorders. Research also shows that other than being healthy and non-toxic, a good fingerprint powder selection and formulation should be based on the following criteria, i.e. small size and fineness of the particles, no chemical or physical attraction of the particles to the surface being examined, the good color contrast, availability, and inexpensiveness [12].

Concerning the difficulty and challenges of making a universal fingerprint powder that satisfies all the criteria listed above, the researchers have produced thousands of powders over many years. Besides, researchers state that no single powder carries all the properties and can best fit fingerprint identification [13]. Moreover, the fingerprints need to be dealt with distinctively. Therefore, it is critical to select the fingerprint visualizing powders [14]. In connection to that, literature shows that previously non-toxic plant materials, food powders [15], cosmetics [9a], food colors [9a], and food items [16] have been used to detect fingerprints. Most prominent of those include turmeric powder, silicone gel, and the ground floor. Compared with these effective powders, Chile-based powders were reported to be poor detectors of fingerprints [12a, 17]. Keeping in view the health hazards and economic constraints of many developing nations Vadivel, Nirmala, and Anbukumaran [1] asserted the need to explore the most commonly available, inexpensive, and non-toxic common materials as fingerprint powders. Hence, adding to the existing body of literature, the current study has considered the nail henna leaves available in Indonesia to prepare and test a non-toxic, cheap, and easily available latent fingerprint powder than the commercially used fingerprint powder.

Moreover, the current study is distinct from the previous studies. The previous research applied the dusting method while using various herbal ingredients, food colors, and edibles to visualize latent fingerprints. In contrast, this research has been carried out to develop a latent fingerprint dusting method by using nail henna leaves to visualize latent fingerprints on non-porous (i.e. aluminum foil, glass preparations, and CD) and porous surfaces (i.e. the spectra paper, HVS paper, and paperboard). In addition to make and test henna leaves powder on various non-porous and porous surfaces, the current study made an advance in the existing body of literature and tested the nail henna leave powder in determining the individuals’ fingerprint patterns. The current study utilized 101 fingerprint samples and evaluated the fingerprint patterns based on three criteria, i.e. ethnicity (Batak, Javanese, and Malay), gender, and blood type.

Literature Review

Several studies on latent fingerprints have been carried out in developing visualization of latent fingerprints by using natural ingredients. In this regard, a literature review Table 1 containing studies that have been conducted from 2011 to 2021 to develop the latent fingerprint powder by using natural, non-toxic, inexpensive, and readily available ingredients is as follows.

Table 1: An overview of natural ingredients used for fingerprints development

Table 1 presents several natural ingredients utilized by various researchers to develop the latent fingerprint powder. However, to the best knowledge of the authors, research lacks the evidence regarding nail henna leaves as a latent fingerprint powder in forensic sciences. Besides, Lawsonia Alba (synonym “Lawsonia inermis L.”), commonly known as nail henna, belongs to the family of “Lythraceae,” the single species in the genus and is found in Indonesia. It appears as a small shrubby tree, 2-6 m high. The nail henna leaves have dye substances that vary from red, burgundy, dark yellow, and reddish-brown, to brown. The nail henna plant generates a reddish yellow molecule called “Lawsone” [19]. This molecule can bind to proteins. Therefore, it can be used to dye skin, hair, nails, silk, and wool [20].

In addition, nail henna leaves also contain active compounds, such as alkaloids, glycosides, flavonoids, phenols, saponins, tannins, and essential oils. Phenols and flavonoids are the most active compounds found. Moreover, nail henna includes naphthoquinone (lawsone), tannins, coumarin, xanthones, flavonoids, phenolic derivatives, aliphatic components, sterols, and triterpenes [19]. It also includes other chemical constituents such as amino acids, glucose, gallic acid, minerals, mannitol, and trace elements [21]. Lawsone, the main ingredient and coloring agent in leaves, comprises 2-hydroxy and 1.4 naphthoquinone with a concentration of 1.0–1.4%. Simultaneously, the henna leaf is used to cure inflammation of finger joints (paniritium) and wounds on the skin. In addition, the flowers, seeds, bark, and roots can cure headaches, arthritis, diarrhea, leprosy, and fever [22].

Materials and Methods

The materials used in this study were 500 g nail henna leaves, HVS paper, spectra paper, paperboard, aluminum foil, glass preparations, CD, 10 ml ethyl acetate, and 40 ml petroleum ether. The used tools include sieves with different sizes, i.e. 60, 80, 100, and 200 mesh, spoon, aluminum plate, container, oven, watch glass, glass beaker, measuring flask, spatula, blender, lifter, and fingerprint brush.

Preparation of Henna Leaves powder

A total of 500 g of henna leaves was dried in the oven. The drying process of the simplicial material was carried out by using an oven at 30 to 90 °C with an optimum temperature of 60 °C for 12 hours to produce dry brown henna leaves. The drying process is very important in the simplicial manufacture because reducing the water content and stopping the enzymatic reactions prevents the deterioration of quality and the destruction of simplicial [21, 23]. Oven drying had higher levels of flavonoids because the heating temperature occurring in the oven was more evenly distributed, and the resulting air circulation was perfect, thus optimizing the drying process. The drying method by using an oven is a good way for the phytochemical content of simplicial [24]. Besides, the used temperature was monitored to complete the whole process quickly.

The leaves were then grounded until smooth by using a blender. The refinement was done for the expansion of particles’ surface, as the greater the contact of the surface of the particles with the solvent, the greater the penetration of the solvent. After that, the powder of henna leaves was sieved by using sieves with sizes of 60, 80, 100, and 200 mesh to obtain a fine powder with a homogeneous size. The fineness of the powder is an important factor in powder making because the finer the powder can better adhere to the latent fingerprints, resulting in better visualization [25]. The powder was then stored in an airtight container at room temperature. Moreover, Figure 1 displays the powder of nail henna leaves from the different sieves as (a) 60, (b) 80, (c) 100, and (d) 200.

Figure 1: The powder of nail henna leaves

Results and Discussion

Fingerprint development on non-porous surface

The physical method of developing, increasing, and visualizing latent fingerprints on various surfaces is termed the dusting method [26]. It mechanically works on the particles of fingerprint powder and sebum components found on the ridge of the skin [27]. To visualize the latent fingerprints, applying the dusting method on non-porous surfaces, i.e. aluminum foil, glass preparations, and CD, the nail henna leaf powder was poured with the aid of brush in circular patterns. The brush movement in circular patterns helped to visualize the latent fingerprints on the non-porous surfaces of the objects. Although using a brush to apply the fingerprints detection powder on non-porous surfaces is a simple technique. However, since the brush, while in contact with the surface, can crush the mold, it can further damage the ridge’s characteristics. Therefore, the excess powder on the surface was removed by using a brush to make printed fingerprints visible. The results of the development and visualization of latent fingerprints by using nail henna leave powder applying dusting method on non-porous surfaces, i.e. aluminum foil, glass preparations, and CD) are depicted in Figures 2 to 4 with powders extracted by using the sieves of four different sizes as (a) 60, (b) 80, (c) 100, and (d) 200.

Figure 2: The latent fingerprints visualization on the aluminum foil surface

Figure 3: The latent fingerprints visualization on the glass preparations surface

Figure 4: The latent fingerprints visualization on the CD surface

Fingerprints on the surface of aluminum foil and glass preparations are very prominent with clear contrast and ridge characteristics while applying the dusting method by using nail henna leaves powder. In contrast, the visualization of the fingerprint development on the CD surface did not give a clear print and ridge due to the slippery surface. When the powder was sprinkled, it could not perfectly adhere to the CD surface. The working principle of fingerprinting powder was the mechanical attachment or extraction of the powder with a latent fingerprint component, i.e. oil, sweat, fat, etc., on a surface. The powder can be attached to the fingerprints in two ways: (i) The powder can be attached with the base material of the fat deposit from the fingerprint, and (ii) the fingerprint deposit components can be dissolved with certain compounds, resulting in a color change [27].

Besides, the results showed that the powder size greatly affects the visualization and the attachment of the powder. The smaller the powder size used, the clearer the visualization of the powder and the easier the process for attaching the powder. The bigger the particles’ size, the lower the color contrast. The smaller the particle size, the more the substance’s surface area, resulting in clear results. Moreover, the fineness of the powder was an important factor in powder making because the finer the powder used, the better the ability to adhere to the latent fingerprint powder and the better its visualization. It has been found that the size of 100 mesh and 200 mesh on aluminum foil and CD surfaces gave results with clear color contrast. It was due to the size of the finer powder, which made it easier for the brush to directly touch the surface and identify the patterns/lines contained in the fingerprints. In addition, it was found that latent prints by using nail henna powder on aluminum foil, glass preparations, and CDs can last more than two weeks. As mentioned earlier, nail henna powder adheres due to form a reddish yellow molecule called Lawsone to bind to proteins to dye skin, hair, nails, silk, and wool fabrics. This compound is a phenolic compound included in the protein group that can color well. The reaction between lawsone and amino acids can be observed in Scheme 1.

Result of latent fingerprint development on paper surface

To develop and visualize the latent fingerprints on porous surfaces, i.e. HVS paper, spectra paper, and paperboard, 50 mg of nail henna powder was mixed in 10 mL of ethyl acetate. Next, it was mixed with 40 mL of petroleum ether. The fingerprint samples were immersed on porous surfaces in the solution, they were dried, and then put in the oven for 1 hour at 150 °C. The results of the development and visualization of the latent fingerprints by using nail henna leave powder applying dusting method on porous surfaces, i.e. HVS paper, spectra paper, and paperboard, are depicted in Figures 5, 6, and 7. The powders were simultaneously extracted by using the sieves of four different sizes as (a) 60, (b) 80, (c) 100, and (d) 200.

The fingerprints were successfully developed with nail henna leaves powder on the surface of HVS paper, spectra paper, and paperboard. Brown color appears on the latent fingerprints found on the paper. These results were consistent with the findings of Jelly, Patton, Lennard, Lewis, and Lim [28], who asserted that Lawsone (1,2- hydroxyl-1,4-naphthoquinone) reacts with the latent fingerprints on the paper’s surface to produce brown color. However, the fingerprint pattern that appears on the paper’s surface was not clearly visible. Although the paper exposed to the solution became brown.

Scheme 1: The reaction between lawson and alanine

Figure 5: The latent fingerprints visualization on the HVS paper surface

Figure 6: The latent fingerprints visualization on the spectra paper surface

Figure 7: The latent fingerprints visualization on the paperboard surface

Otherwise, fingerprints were not clearly visible. Moreover, Scheme 2 exhibits the reaction of Lawsone in nail henna leaves with ethyl acetate and petroleum ether to produce an acetic acid 1,4-dimethylene-1,4-dihydro-naphthalene-2-ylester.

In addition, Scheme 3 shows the reaction of lawsone in nail henna leaves with ethyl acetate and petroleum ether to produce acetic acid 1,4-dimethylene-1,4-dihydro-naphthalene. The reaction of acetic acid 1,4-dimethylene-1,4-dihydro-naphthalene added to alanine gives 2- (1,4-dimethylene-1,4-dihydro-naphthalene-2-yloxycarbonylamino) -propionic acid.

Lawsone (1,2- hydroxyl-1,4-naphthoquinone) reacts with latent fingerprints on the paper’s surface to give a brown color. Lawsone is a naphthoquinone, a group of compounds that react with amino acids. In addition, 1,2-naphthoquinone-4-sulfonate has been used to determine amino acids by forming compounds and producing a brown pigment.

Scheme 2: The reaction of lawsone with ethyl acetate and petroleum

Scheme 3: The reaction of lawsone with ethyl acetate and petroleum plus alanine

Besides, amino acids are important components contributing to the latent fingerprints, especially on porous surfaces, such as paper, because they adhere to paper fibers and are durable [28]. However, despite all this evidence of chemical reactions, lawsone in nail henna leaves that produce sufficient pieces of evidence of fingerprint visualizations, the results of the current study did not support the development and visualization of fingerprint patterns of nail henna leaves powder on porous surfaces, i.e. HVS paper, spectra paper, and paperboard. This can be based on the fact that apart from the ingredients used to develop the powders to detect the fingerprints’ patterns develop on various surfaces; scientists should also consider other factors, i.e. the object of the surface, the skin condition of the individual, the type and amount of residue on the skin of the object, etc. It also depends on the quality of latent fingerprints left by the individual on the surface. In the current study, it was found that no prominent brown coloration was produced based on visualizing the fingerprints left by the sample on the papers used as porous surfaces. It further depicts that no chemical reaction occurred between the paper and the fingerprints. Therefore, we could not visualize the fingerprint patterns of the samples on porous surfaces by using nail henna leaves powder by applying the dusting method.

Fingerprint patterns based on tribe, blood type, and gender

The fingerprint patterns are generally divided into three forms: Arch, Loop, and Whorl [29]. The arch pattern is a curved pattern without a triradius, the loop pattern is curved and has a triradius, and the whorl pattern is a circle with two triradius [30]. This study used 101 fingerprint samples based on tribe (Batak, Javanese, and Malay), blood type, and gender. The sample was collected from the students by using the Laboratory of Chemistry, and Faculty of Mathematics and Natural Sciences, State University of Medan. They were briefed about the purpose of the study and the experimental requirements and were requested to participate voluntarily.

Fingerprints based on tribe

Figure 8 demonstrates that 101 samples showed the highest presentation on the loop fingerprint patterns, followed by whorl, and then by arch. The percentage of the loop fingerprint pattern was 23.1 percent for Malay, 19 percent for the Javanese, and 16.7 percent for the Batak ethnic group. This further reflects the dominance of the loop fingerprint pattern over the other two fingerprint patterns. These findings are in accordance with Dhaneshwar, Kaur, and Kaur [30] and Uma, Mazalan, Ramlan, Adnan, and Soe [31], who reported the highest percentage of loops fingerprint patterns, followed by whorl, and then by arch among the respondents of their study. Moreover, after calculating the presentation of the fingerprint pattern, the Malay tribe has the highest loop pattern than the Javanese and Batak loops. Meanwhile, the Javanese loop pattern was the dominant pattern, and then the whorls the pattern. The frequency of the whorl and arch fingerprint patterns is also exhibited in Figure 8 that depicts that whorl patterns follow different results than loop patterns. It further shows that the Batak tribe showed the highest percentage of whorl patterns, followed by Javanese and Malay. Finally, arch patterns were rare in all three tribes.

Fingerprints based on gender

Based on the research results, out of the 101 samples, 41 (40.6 percent) were males, and 60 (59.4 percent) were females. This was according to the data set of Eboh (2013), who researched Delta State University students, Nigeria, and mentioned that the number of female participants was more than men. The highest percentage was the loop fingerprint pattern, followed by whorl, and then by arch. The current results followed the findings of Purbasari and Sumadji [32], who asserted the fingerprint pattern has the highest percentage of loops, followed by whorl, and then by arch. Moreover, the results revealed that the percentage of loop fingerprint patterns was 45.5 percent in women and 13.3 percent in men showing that women have a higher percentage than men, as illustratred in Figure 9. At the same time, the whorl fingerprint pattern of women was 32.2 percent, while it was 6.6 percent for men. The arch fingerprint patterns were 2.2 and 0 percent for women and men, respectively. Consistent with the data set results for tribes, the findings for gender also show the highest percentage of loop patterns among females and males, followed by whorl and arch patterns.

Figure 8: Fingerprints based on tribe

Figure 9: Fingerprint patterns based on sex

Fingerprints based on blood group

Apart from ethnicity, the blood type can also identify an individual. Karl Landsteiner was a scientist who discovered the blood grouping system in 1901. To date, 36 blood group groups have been identified by various distribution patterns of the human race [33]. The ABO and Rhesus blood group systems are blood group groups playing an important role in clinical purposes [33]. The ABO system has been further classified into A, B, AB, and O against the corresponding antigens in red blood cells. In contrast, the D antigen is the basis of the classification of the Rhesus system into Rhesus positive and Rhesus negative [34]. The results of the ABO blood group analysis revealed that the highest fingerprint pattern was the loop fingerprint pattern identified in the O blood group (31.1%), followed by the B blood group B (12.2%), the AB blood group (8.8%), and the A blood group (6.6%). The results of this study were similar to Eboh [35] research which showed that the dominant blood type was blood type O (55.9%), followed by blood type A (22.4%), blood group B (20.4%), and then blood group AB (1.2%). This further reflects the authenticity of the nail henna leaf powder to detect the latent fingerprints. Moreover, the results revealed that the whorl fingerprint patterns on the O blood group were 18.8 percent, followed by the B blood group (8.8%), blood group AB (5.5%), and blood group A (5.5%). The arch fingerprint patterns on the AB blood group were 5 percent, followed by the B blood group (1%), blood group O (1%), and blood group A (0%). Moreover, Figure 10 displays the percentage of fingerprint patterns based on the blood group.

Figure 10: Fingerprint pattern based on blood group

Finally, it can be mentioned that the fingerprint patterns are biological variations different from one ethnic group to another, between men and women, and among blood groups.

Conclusion

Following the study results, we can conclude that fingerprints have been developed on various surfaces by using nail henna leaves (Lawsonia Inermis Linn.). For instance, fingerprints were developed on the aluminum foil and glass preparation surfaces by using nail henna powder with a clear contrast and ridge characteristics. However, on the CD surface, the visualization of the fingerprint development did not give a clear ridge print. While the development by using paper media was not successful, some papers did not have a brown discoloration on the fingerprints left by the sample, and the fingerprint patterns were not clearly visible. The effect of the sieve or particle size of the nail henna leaf powder on the visualization of latent fingerprints was very clear. For instance, the finer the powder was used, the better was the ability to adhere to the latent fingerprint powder, and the resultant visualization was better. On the aluminum foil and glass preparations surfaces, the powder size of 60 and 80 mesh did not demonstrate good results visualizing the latent fingerprints of the sample. It happened because the powder could not cover the whole surfaces of the aluminum foil and glass preparations. Meanwhile, 100 and 200 mesh powder sizes provided the good color contrast and ridge characteristics. In contrast, although nail henna leaves powder on porous surfaces of various papers indicated the color change and identified fingerprints. Still, it could not develop and visualize the fingerprint patterns. This might be due to the lack of chemical reaction between fingerprints and papers surface. However, future researchers can further explore it by carefully observing the types of skin and residue on the samples’ fingerprints to devise favorable results. Besides, the loop patterns showed the highest percentage of fingerprint patterns among the Malay tribe, followed by Batak, and Java tribes. Similarly, based on gender, the loop patterns indicated the highest percentage of fingerprint patterns among women than men. Finally, the highest percentage of fingerprint patterns formed based on blood group was also the loop pattern of varied from blood group O followed by blood group B, AB, and simultaneously. Furthermore, these results depict that the henna nail leaf powder could be developed to visualize fingerprints on non-porous surfaces and help to identify patterns based on ethnicity, gender, and blood group.

Acknowledgments

The author would like to thank all parties participated in being the fingerprint sample in this study. Especially they would like to present their sincere gratitude to the Laboratory of Chemistry, Faculty of Mathematics and Natural Sciences, State University of Medan, and the Forensic Laboratory of the North Sumatra Police.

Disclosure Statement

No potential conflict of interest was reported by the authors.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Authors' contributions

All authors contributed to data analysis, drafting, and revising of the paper and agreed to be responsible for all the aspects of this work.

ORCID:

Sri Adelila Sari

https://orcid.org/0000-0001-5911-6575

Desi Heriyanti Nasution

https://orcid.org/0000-0001-5317-8724

HOW TO CITE THIS ARTICLE

Sri Adelila Sari, Desi Heriyanti Nasution. Development of Nail Henna (Lawsonia Inermis Linn.) Leaf Powder as a Latent Fingerprint Visualization on Non-Porous and Porous Surfaces. J. Med. Chem. Sci., 2023, 6(3) 540-552

https://doi.org/10.26655/JMCHEMSCI.2023.3.11    

URL: http://www.jmchemsci.com/article_157811.html