**3. Results and discussion**

Overall, we found 1248 issues characterized by the bibliometric parameters shown in **Table 1**.

The number of issues published per year is described in **Figure 1**. As it is evident in the period 2009–2011, the number of papers published per year was very low (<10/year); then it increased with a linear trend, to reach about 350 issues published in 2017.

The time trend of citations (sum of cited per year) has a different pattern, described by more than linear pattern, as reported in **Figure 2**.

Interestingly, the distribution of cites per year, as shown in **Figure 3**, in keeping with the Bedford's, follows a power law, with a negative exponent.

In addition it has been possible to compute the main parameters of cites/year distribution (see **Table 2**).

To explore the temporal pattern of the most important themes studied, we analyzed the burst in citations referred to specific keywords (see **Table 3** for the list of citation bursts identified).


Interestingly, we investigated the number of issues published by each country, thus estimating the contribution of different countries in research on graphene application in medicine (**Table 4**). These data demonstrate that graphene and graphene-based material are used in a wide variety of application in biomedicine such as cell and stem cell culture, translational medicine, bioengineering, toxicology, and development, thus confirming that these materials

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are becoming to represent a reality in life sciences.

**Figure 2.** Graph showing the time trend of sum of cited per year.

**Figure 1.** Graph showing the time trend of issues published per year.

**Table 1.** Bibliometric parameters referred to the studied dataset.

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**Figure 1.** Graph showing the time trend of issues published per year.

• **Number of citable issues:** are considered **e**xclusively articles, reviews, and conference

• **Number of cites per documents:** it is the number of citation of documents published in

generated temporal visualization of burst detection analysis of ISI keywords used in the papers. The geolocation of author collaboration was realized using Citespace (http://cluster. cis.drexel.edu/~cchen/citespace/) and Google Earth (https://www.google.it/intl/it/earth/).

Overall, we found 1248 issues characterized by the bibliometric parameters shown in **Table 1**. The number of issues published per year is described in **Figure 1**. As it is evident in the period 2009–2011, the number of papers published per year was very low (<10/year); then it

The time trend of citations (sum of cited per year) has a different pattern, described by more

Interestingly, the distribution of cites per year, as shown in **Figure 3**, in keeping with the

In addition it has been possible to compute the main parameters of cites/year distribution

To explore the temporal pattern of the most important themes studied, we analyzed the burst in citations referred to specific keywords (see **Table 3** for the list of citation bursts identified).

papers has at least *h* citations each,

Tool (Sci2

Team). We

• **H index:** a topic/journal/author has index *h* if *h* of its *Np*

**2.2. Temporal and geospatial analysis**

**3. Results and discussion**

(see **Table 2**).

than linear pattern, as reported in **Figure 2**.

Bedford's, follows a power law, with a negative exponent.

**Table 1.** Bibliometric parameters referred to the studied dataset.

and the other (*Np* − *h*) papers have no more than *h* citations each.

The data were processed for temporal and geospatial analysis by Sci2

increased with a linear trend, to reach about 350 issues published in 2017.

**Parameter Value** *H*-index 67 Average citation per item 17.65 Sum of time cited 2647 Citing articles 14,055

papers.

86 Scientometrics

specific years.

**Figure 2.** Graph showing the time trend of sum of cited per year.

Interestingly, we investigated the number of issues published by each country, thus estimating the contribution of different countries in research on graphene application in medicine (**Table 4**). These data demonstrate that graphene and graphene-based material are used in a wide variety of application in biomedicine such as cell and stem cell culture, translational medicine, bioengineering, toxicology, and development, thus confirming that these materials are becoming to represent a reality in life sciences.

**Term Span Weight Begin End** Accelerated-differentiation 2 30.562 2013 2014 Erk1–2 2 46.299 2012 2013 Evidenced-by 2 33.865 2015 2016 Fe3o4-go 3 36.129 2011 2013 Fe3o4-go-nanocomposites 3 27.411 2011 2013 Fe3o4-nanoparticles 2 36.777 2010 2011 Film-is 2 28.366 2012 2013 Films-of 5 31.674 2010 2014 Films-were 3 35.185 2011 2013 Films-with 3 31.612 2011 2013 Functional-theory 5 26.907 2006 2010 G-and 2 39.214 2011 2012 G-and-go 2 41.282 2011 2012 Genotoxicity-of 2 27.537 2012 2013 Graphene-content 2 43.921 2014 2015 Graphene-films 4 5.692 2009 2012 Graphene-nanocomposites 4 33.876 2011 2014 Graphene-nanoflakes 4 32.128 2011 2014 Graphene-nanostructures 2 36.785 2013 2014 Added-to 5 35.578 2009 2013 Graphene-sheets 8 130.541 2006 2013 Graphene-using 2 27.779 2013 2014 Graphite-oxide 3 43.642 2011 2013 Growth-of 3 48.996 2013 2015 Hectorite-clay 2 29.144 2013 2014 Adhesive-performance 2 38.487 2011 2012 Human-neural 4 41.777 2011 2014 Human-neural-stem 4 40.028 2011 2014 Human-neural-stem-cells 4 33.938 2011 2014 Adsorption-on 8 2.73 2006 2013 Indicates-that 2 26.756 2014 2015 Induction-of 2 32.246 2012 2013 Interaction-between 4 27.177 2010 2013 Investigated-using 3 44.764 2012 2014

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**Figure 3.** Graph showing the distribution of cites/year.


**Table 2.** Citation parameters.

As it is evident, the most of issues have been published in China, with a total number of issues that accounts for about a third of worldwide production, followed by the United States and South Korea, India, and Iran. This datum is very interesting, because it demonstrates that Asiatic countries are the most important contributor, at least quantitative point of view, to this such important field of research.

To better explore the context to which the research is referred, we assessed the subject categories, as reported in **Table 5**.

As it is evident from the analysis of **Table 5**, the most of issues are indexed in nonbiological fields (materials science, chemistry, science and technology, physics, and engineering) rather than in biological fields. This seems to indicate that, to date, the research is led and defined by hard science scientist and, possibly, the contribution of researched belonging to biological and medical areas could be markedly increased in next years.


As it is evident, the most of issues have been published in China, with a total number of issues that accounts for about a third of worldwide production, followed by the United States and South Korea, India, and Iran. This datum is very interesting, because it demonstrates that Asiatic countries are the most important contributor, at least quantitative point of view, to this

To better explore the context to which the research is referred, we assessed the subject catego-

As it is evident from the analysis of **Table 5**, the most of issues are indexed in nonbiological fields (materials science, chemistry, science and technology, physics, and engineering) rather than in biological fields. This seems to indicate that, to date, the research is led and defined by hard science scientist and, possibly, the contribution of researched belonging to biological

and medical areas could be markedly increased in next years.

such important field of research.

**Figure 3.** Graph showing the distribution of cites/year.

**Parameter Value** Max 117 95° percentile 17.96825 75° percentile 6 Median 2.25 25° percentile 0.666667 5° percentile 0 Min 0

ries, as reported in **Table 5**.

**Table 2.** Citation parameters.

88 Scientometrics


**Term Span Weight Begin End** Translational-medical-research 2 92.302 2013 2014 Transmission-electron-microscope 2 27.348 2012 2013 Van-der 8 39.866 2006 2013 Van-der-waals 8 39.866 2006 2013 Walled-carbon-nanotubes 8 32.082 2006 2013 Water-molecules 2 52.214 2012 2013 Water-soluble 3 48.753 2012 2014 wt-wt 2 29.572 2012 2013 ×-10 2 31.433 2010 2011 Beta-tcp 2 37.851 2015 2016 Bioactivity-of 3 32.757 2012 2014 2015-elsevier-b 2 76.506 2015 2016 bmp-2 2 122.945 2013 2014 Bone-cells 4 29.536 2011 2014 Bone-cement 2 29.572 2012 2013 Cancer-cells-and 2 43.062 2013 2014 Cancer-stem 2 59.119 2014 2015 Cancer-stem-cells 2 55.153 2014 2015 Carbon-nanotubes 5 83.764 2006 2010 Cell-differentiation 3 28.996 2012 2014 Cell-membranes 2 26.423 2014 2015 Cell-to 3 42.168 2011 2013 Cells-on-the 2 29.197 2013 2014 Cellular-uptake 2 27.088 2014 2015 Chemical-inducers 2 27.537 2012 2013 Chitosan-and 2 30.566 2010 2011 Chitosan-composite 2 27.779 2013 2014 Chitosan-film 3 27.411 2011 2013 Collagen-scaffolds 2 43.921 2014 2015

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3d-rgo 4 39.778 2016 3d-rgo-ppy 4 26.517 2016

Composite-film 4 28.754 2011 2014 Composite-films 4 63.612 2011 2014 Concentration-of 2 59.312 2011 2012 A Scientometric Study on Graphene and Related Graphene-Based Materials in Medicine http://dx.doi.org/10.5772/intechopen.77288 91


**Term Span Weight Begin End** Ag-nanoparticles 3 9.15 2010 2012 Mammalian-cells 2 32.251 2010 2011 Medical-research 2 92.302 2013 2014 Metabolic-activity 2 32.637 2013 2014 Mineralization-of 2 30.056 2014 2015 Modified-electrode 3 39.563 2010 2012 Molecular-dynamics 8 38.142 2006 2013 Monitoring-of 2 36.127 2012 2013 Multi-walled 2 34.922 2012 2013 Neural-stem 3 56.255 2011 2013 Neural-stem-cell 3 27.096 2011 2013 Neural-stem-cells 4 33.218 2011 2014 Nitrogen-doped 2 34.021 2014 2015 Oxidation-of 3 2.979 2010 2012 Antibacterial-activity 3 39.684 2010 2012 Peak-current 3 38.873 2010 2012 Porous-scaffolds 2 38.569 2015 2016 Prepared-via 3 29.212 2013 2015 Properties-of-graphene 4 34.088 2010 2013 Protein-corona 2 36.322 2014 2015

90 Scientometrics

Rgo-ppy 4 28.174 2016

Schwann-cells 2 38.247 2015 2016 Sheets-in 2 55.564 2013 2014 Sheets-in-the 2 31.928 2013 2014 Sheets-on 2 36.322 2014 2015 Similar-to-1 2 3.542 2013 2014 Size-dependent 2 29.383 2012 2013 Stabilizing-agent 2 32.246 2012 2013 Stem-cell-differentiation 4 26.513 2010 2013 Studied-by 4 28.884 2012 2015 Surface-chemistry 2 27.123 2013 2014 Time-dependent 2 26.413 2013 2014 Traditional-Chinese 2 40.822 2010 2011 Translational-medical 2 97.161 2013 2014


**Table 3.** Citation bursts.


The same trend could be identified looking on the WC, i.e., the classification system adopted

**Number of issues % on total issues published Countries/territories**

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 1.1 Brazil 0.9 Poland 0.7 Romania 0.7 Denmark 0.7 Sweden 0.6 France 0.6 Russia 0.6 Turkey 0.5 Malaysia 0.5 Portugal 0.5 Egypt 0.4 Argentina 0.4 Czech Republic

 0.4 Finland 0.4 Belgium 0.4 Switzerland 0.3 Israel 0.3 Thailand 0.2 Greece 0.2 Mexico

0.2 The Netherlands

 0.2 Serbia 0.2 Ireland 0.2 Morocco 0.1 Pakistan 0.1 Scotland 0.1 Vietnam

From these data, we could infer that we are seeing a first phase of the use of graphene and graphene-based materials, in which the studies on basic issues (synthesis, chemical characterization, description of chemical and physical properties) rather than the application in biology

by Web of Science (see **Figures 4** and **5**).

**Table 4.** Number of issues per country.

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**Table 4.** Number of issues per country.

**Number of issues % on total issues published Countries/territories**

**Term Span Weight Begin End** Conductivity-of 2 29.085 2014 2015 Cultured-on-the 2 30.056 2014 2015 Cytotoxicity-of 3 48.985 2012 2014 Cytotoxicity-of-the 3 26.639 2012 2014 5-×-10 2 26.522 2010 2011 Delivery-of 2 61.189 2013 2014 Density-functional 5 26.907 2006 2010 Density-functional-theory 5 26.907 2006 2010 Der-waals 8 39.866 2006 2013 Differentiation-of-human 3 27.305 2011 2013 Doped-graphene 2 28.541 2013 2014 Embryonic-stem 3 37.831 2012 2014 Embryonic-stem-cells 3 31.442 2012 2014 Energy 4 27.199 2006 2009

 14.0 The United States 9.4 South Korea

2.4 The United Kingdom

34.0 China

**Table 3.** Citation bursts.

Scientometrics

 4.6 India 4.2 Iran 2.5 Spain 2.4 Singapore

 2.3 Australia 2.3 England 2.1 Taiwan 2.1 Italy 1.8 Japan 1.7 Germany 1.3 Canada 1.2 Saudi Arabia

The same trend could be identified looking on the WC, i.e., the classification system adopted by Web of Science (see **Figures 4** and **5**).

From these data, we could infer that we are seeing a first phase of the use of graphene and graphene-based materials, in which the studies on basic issues (synthesis, chemical characterization, description of chemical and physical properties) rather than the application in biology


**Issues Subject category** Hematology Immunology

 Medical informatics Microbiology

 Telecommunications Transplantation

**Table 5.** List of subject categories.

 Neurosciences and neurology Nutrition and dietetics Ophthalmology Pathology Physiology Plant sciences

 Information science and library science Mathematical and computational biology

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Radiology, nuclear medicine, and medical imaging

**Figure 4.** Classification of subject categories (the diameter is proportion to the number of issues).


**Table 5.** List of subject categories.

**Issues Subject category** Materials science Chemistry

 Physics Engineering Electrochemistry Polymer science Biophysics

Scientometrics

Science and technology, other topics

 Biochemistry and molecular biology Biotechnology and applied microbiology

 Pharmacology and pharmacy Environmental sciences and ecology

Instruments and instrumentation

 Metallurgy and metallurgical engineering Research and experimental medicine

Dentistry, oral surgery, and medicine

 Life sciences and biomedicine, other topics Public, environmental, and occupational health

 Education and educational research Endocrinology and metabolism General and internal medicine

Genetics and heredity

Food science and technology

Energy and fuels

 Computer science Crystallography

 Mechanics Microscopy Oncology

 Spectroscopy Water resources Acoustics

 Toxicology Optics Cell biology

**Figure 4.** Classification of subject categories (the diameter is proportion to the number of issues).

differentiation, from the realization of scaffolds to toxicological studies), the research activity on these issues seems still in an early stage, characterized by the physical and chemical characterization of materials, rather than the massive application in biomedicine and

A Scientometric Study on Graphene and Related Graphene-Based Materials in Medicine

Juliana Sofia Simoes Machado is granted by Rep-Eat-H2020-MSCA-COFUND-2015 No. 713714.

, Alessandra Ordinelli1

[1] Mao HY, Laurent S, Chen W, Akhavan O, Imani M, Ashkarran AA, Mahmoudi M. Graphene: Promises, facts, opportunities, and challenges in nanomedicine. Chemical Re-

[2] Park SY, Park J, Sim SH, Sung MG, Kim KS, Hong BH, Hong S. Enhanced differentiation of human neural stem cells into neurons on graphene. Advanced Materials.

[3] Li N, Zhang Q, Gao S, Song Q, Huang R, Wang L, Liu L, Dai J, Tang M, Cheng G. Threedimensional graphene foam as a biocompatible and conductive scaffold for neural stem

[4] Ping J, Zhou Y, Wu Y, Papper V, Boujday S, Marks RS, Steele TW. Recent advances in aptasensors based on graphene and graphene-like nanomaterials. Biosensors & Bio-

1 Faculty of Bioscience and Technology for Food, Agriculture and Environment,

2 Istituto Zooprofilattico Sperimentale "G. Caporale", Teramo, Italy

views. 2013;**113**(5):3407-3424. DOI: 10.1021/cr300335p

2011;**23**(36):H263-H267. DOI: 10.1002/adma.201101503

cells. Scientific Reports. 2013;**3**:1604. DOI: 10.1038/srep01604

electronics. 2015;**64**:373-385. DOI: 10.1016/j.bios.2014.08.090

, Juliana Sofia Somoes Machado1

http://dx.doi.org/10.5772/intechopen.77288

,

97

bioengineering.

**Acknowledgements**

**Conflict of interest**

**Author details**

Nicola Bernabò1

**References**

The authors declare that they have no competing interests.

\*, Rosa Ciccarelli1

\*Address all correspondence to: nbernabo@unite.it

Mauro Mattioli1,2 and Barbara Barboni1

University of Teramo, Italy

**Figure 5.** Classification of WoS categories (the diameter is proportion to the number of issues).

and medicine are predominating. Likely, it is possible to hypothesize that in next years, the contribution of life scientists and researchers and clinicians involved in medical field could acquire higher importance.
