Titanium Dioxide Nanoparticle (TiO2 NP) Induces Toxic Effects on LA-9 Mouse Fibroblast Cell Line.

BACKGROUND/AIMS: Titanium dioxide nanoparticles (TiO2 NPs) are extensively applied in the industry due to their photocatalytic potential, low cost, and considerably low toxicity. However, new unrelated physicochemical properties and the wide use of nanoparticles brought concern about their toxic effects. Thereby, we evaluated the cytotoxicity of a TiO2 NP composed of anatase and functionalized with sodium carboxylate ligands in a murine fibroblast cell line (LA-9). METHODS: Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), and ATR-FTIR spectroscopy were applied to determine nanoparticle physicochemical properties. The cell viability (MTT assay) and clonogenic survival were analyzed in fibroblasts exposed to TiO2 NP (50, 150, and 250 µg/mL) after 24h. Moreover, oxidative stress, proinflammatory state, and apoptosis were evaluated after 24h. RESULTS: TiO2 NP characterization showed an increased hydrodynamic size (3.57 to 7.62 nm) due to solvent composition and a heterogeneity dispersion in water and cell culture media. Also, we observed a zeta potential increased from -20 to -11 mV in function of protein adsorption. TiO2 NP reduced fibroblast cell viability and induced ROS production at the highest concentrations (150 and 250 µg/mL). Moreover, TiO2 NP reduced the fibroblasts clonogenic survival at the highest concentration (250 µg/mL) on the 7th day after the 24h exposure. Nevertheless, TiO2 NP did not affect the fibroblast proinflammatory cytokines (IL-6 and TNF) secretion at any condition. Early and late apoptotic fibroblast cells were detected only at 150 µg/mL TiO2 NP after 24h. CONCLUSION: Probably, TiO2 NP photocatalytic activity unbalanced ROS production which induced apoptosis and consequently reduced cell viability and metabolic activity at higher concentrations.

Study of the Counter Cation Effects on the Supramolecular Structure and Electronic Properties of a Dianionic Oxamate-Based {NiII2} Helicate.

Herein, we describe the synthesis, crystal structure, and electronic properties of {[K2(dmso)(H2O)5][Ni2(H2mpba)3]·dmso·2H2O}n (1) and [Ni(H2O)6][Ni2(H2mpba)3]·3CH3OH·4H2O (2) [dmso = dimethyl sulfoxide; CH3OH = methanol; and H4mpba = 1,3-phenylenebis(oxamic acid)] bearing the [Ni2(H2mpba)3]2- helicate, hereafter referred to as {NiII2}. SHAPE software calculations indicate that the coordination geometry of all the NiII atoms in 1 and 2 is a distorted octahedron (Oh) whereas the coordination environments for K1 and K2 atoms in 1 are Snub disphenoid J84 (D2d) and distorted octahedron (Oh), respectively. The {NiII2} helicate in 1 is connected by K+ counter cations yielding a 2D coordination network with sql topology. In contrast to 1, the electroneutrality of the triple-stranded [Ni2(H2mpba)3] 2- dinuclear motif in 2 is achieved by a [Ni(H2O)6]2+ complex cation, where the three neighboring {NiII2} units interact in a supramolecular fashion through four R22(10) homosynthons yielding a 2D array. Voltammetric measurements reveal that both compounds are redox active (with the NiII/NiI pair being mediated by OH- ions) but with differences in formal potentials that reflect changes in the energy levels of molecular orbitals. The NiII ions from the helicate and the counter-ion (complex cation) in 2 can be reversibly reduced, resulting in the highest faradaic current intensities. The redox reactions in 1 also occur in an alkaline medium but at higher formal potentials. The connection of the helicate with the K+ counter cation has an impact on the energy levels of the molecular orbitals; this experimental behavior was further supported by X-ray absorption near-edge spectroscopy (XANES) experiments and computational calculations.

Comparing extracellular vesicles and cell membranes as biocompatible coatings for gold nanorods: Implications for targeted theranostics.

Extracellular vesicles (EVs) and cell membrane nanoghosts are excellent coatings for nanomaterials, providing enhanced delivery in the target sites and evasion of the immune system. These cell-derived coatings allow the exploration of the delivery properties of the nanoparticles without stimulation of the immune system. Despite the advances reported on the use of EVs and cell-membrane coatings for nanomedicine applications, there are no standards to compare the benefits and main differences between these technologies. Here we investigated macrophage-derived EVs and cell membranes-coated gold nanorods and compared both systems in terms of target delivery in cancer and stromal cells. Our results reveal a higher tendency of EV-coated nanorods to interact with macrophages yet both EV and cell membrane-coated nanorods were internalized in the metastatic breast cancer cells. The main differences between these nanoparticles are related to the presence or absence of CD47 in the coating material, not usually addressed in EVs characterization. Our findings highlight important delivery differences exhibited by EVs- or cell membranes- coated nanorods which understanding may be important to the design and development of theragnostic nanomaterials using these coatings for target delivery.

Toxicological effects of the mixed iron oxide nanoparticle (Fe3O4 NP) on murine fibroblasts LA-9.

The increase in large-scale production of magnetic nanoparticles (NP) associated with the incomplete comprehensive knowledge regarding the potential risks of their use on environmental and human health makes it necessary to study the biological effects of these particles on organisms at the cellular level. The aim of this study to examine the cellular effects on fibroblast lineage LA-9 after exposure to mixed iron oxide NP (Fe3O4 NP). The following analyses were performed: field emission gun-scanning electron microscopy (SEM-FEG), dynamic light scattering (DLS), zeta potential, ultraviolet/visible region spectroscopy (UV/VIS), and attenuated total reactance-Fourier transform infrared (ATR-FTIR) spectroscopy analyses for characterization of the NP. The assays included cell viability, morphology, clonogenic potential, oxidative stress as measurement of reactive oxygen species (ROS) and nitric oxide (NO) levels, cytokines quantification interleukin 6 (IL-6) and tumor necrosis factor (TNF), NP uptake, and cell death. The size of Fe3O4 NP was 26.3 nm when evaluated in water through DLS. Fe3O4 NP did not reduce fibroblast cell viability until the highest concentration tested (250 µg/ml), which showed a decrease in clonogenic potential as well as small morphological changes after exposure for 48 and 72 hr. The NP concentration of 250 µg/ml induced enhanced ROS and NO production after 24 hr treatment. The uptake assay exhibited time-dependent Fe3O4 NP internalization at all concentrations tested with no significant cell death. Hence, exposure of fibroblasts to Fe3O4 NP-induced oxidative stress but not reduced cell viability or death. However, the decrease in the clonogenic potential at the highest concentration demonstrates cytotoxic effects attributed to Fe3O4 NP which occurred on the 7th day after exposure.

Functionalized Titanium Nanoparticles Induce Oxidative Stress and Cell Death in Human Skin Cells.

Purpose: Nanoparticles are resources of advanced nanotechnology being present in several products. Titanium dioxide nanoparticles are among the five most widely used NP currently expanding their benefits from the oil industry to the areas of diagnostic medicine due to their properties and small size. However, its impact on human health is still controversial in the literature. We aimed to evaluate the cytotoxicity of a new titanium NP functionalized with sodium carboxylic ligand (COOH-Na+) in human keratinocytes (HaCaT) and human fibroblasts (HDFn). Methods: The physical-chemical characterization was performed by the transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential techniques, respectively. MTT and LDH assays were used to assess cytotoxicity and cell membrane damage respectively, ELISA to identify the inflammatory profile and, reactive oxygen species assay and cytometry to detect reactive oxygen species and their relationship with apoptosis/necrosis mechanisms. Results: The results demonstrated a decrease in cell viability at the highest concentrations tested for both cell lines, but no change in LDH release was detected for the HaCaT. The cell membrane damage was found only at 100.0 µg/mL for the HDFn. It was demonstrated that cytotoxicity in the highest concentrations evaluated for both cell lines for the 72 h period. The HDFn showed damage to the cell membrane at a concentration of 100 µg/mL followed by a significant increase in reactive oxygen species production. No inflammatory profile was detected. The HaCaT showed apoptosis when exposed to the highest concentration evaluated and HDFn showed both apoptosis and necrosis for the same concentration. Conclusion: Thus, it is possible to conclude that the cytotoxicity mechanism differs according to the cell type evaluated, with HDFn being the most sensitive line in this case, and this mechanism can be defined in a dose and time dependent manner, since the highest concentrations also triggered death cell.

Decyl esters production from soybean-based oils catalyzed by lipase immobilized on differently functionalized rice husk silica and their characterization as potential biolubricants.

This study aimed the enzymatic decyl esters production by hydroesterification, a two-step process consisting of hydrolysis of refined soybean (RSBO) or used soybean cooking (USCO) oils to produce free fatty acids (FFA) and further esterification of purified FFA. Using free lipase from Candida rugosa (CRL), about 98% hydrolyses for both oils have been observed after 180 min of reaction using a CRL loading of 50 U g-1 of reaction mixture, 40 °C, and a mechanical stirring of 1500 rpm. FFA esterification with decanol in solvent-free systems was performed using lipase from Thermomyces lanuginosus (TLL) immobilized by physical adsorption on silica particles extracted from rice husk, an agricultural waste. For such purpose, non-functionalized (SiO2) or functionalized rice husk silica bearing octyl (Octyl-SiO2) or phenyl (Phe-SiO2) groups have been used as immobilization supports. Protein amounts between 22 and 28 mg g-1 of support were observed. When used in the esterification, they enabled a FFA conversion of 81.3-87.6% after 90-300 min of reaction. Lipozyme TL IM, a commercial immobilized TLL, exhibited similar performance compared to TLL-Octyl-SiO2 (FFA conversion ≈90% after 90-120 min of reaction). However, high operational stability after fifteen successive esterification batches was observed only for TLL immobilized on Octyl-SiO2 (activity retention of ≈90% using both FFA sources). The produced decyl esters presented good characteristics as potential biolubricants according to standard methods (ASTM) and thermal analysis.

Preclinical Evaluation of Polymeric Nanocomposite Containing Pregabalin for Sustained Release as Potential Therapy for Neuropathic Pain.

This study offers a novel oral pregabalin (PG)-loaded drug delivery system based on chitosan and hypromellose phthalate-based polymeric nanocomposite in order to treat neuropathic pain (PG-PN). PG-PN has a particle size of 432 ± 20 nm, a polydispersity index of 0.238 ± 0.001, a zeta potential of +19.0 ± 0.9 mV, a pH of 5.7 ± 0.06, and a spherical shape. Thermal and infrared spectroscopy confirmed nanocomposite generation. PG-PN pharmacokinetics was studied after a single oral dose in male Wistar rats. PG-PN showed greater distribution and clearance than free PG. The antinociceptive effect of PG-PN in neuropathic pain rats was tested by using the chronic constriction injury model. The parameter investigated was the mechanical nociceptive threshold measured by the von Frey filaments test; PG-PN showed a longer antinociceptive effect than free PG. The rota-rod and barbiturate sleep induction procedures were used to determine adverse effects; the criteria included motor deficit and sedative effects. PG-PN and free PG had plenty of motors. PG-PN exhibited a less sedative effect than free PG. By prolonging the antinociceptive effect and decreasing the unfavorable effects, polymeric nanocomposites with pregabalin have shown promise in treating neuropathic pain.

Apoptosis and Oxidative Stress Triggered by Carbon Black Nanoparticle in the LA-9 Fibroblast.

BACKGROUND/AIMS: A new type of nanoparticle, called NP CB-EDA (Black Carbon modified with ethylenediamine), is commonly used in the oil industry. In the literature, few studies are found in biological models, making NP-EDA potential cytotoxicity in organisms unclear. As its large surface area is capable of interacting with the biological system, that interaction could lead to factors harmful to health. The objective of this study was to investigate the cytotoxic effect of NP CB-EDA on fibroblasts LA-9 at 24 and 48 hours, at different concentrations of the nanoparticle (1, 50, 250, 500 and 1000 µg/ml). METHODS: NP CB-EDA was characterized by TEM microscopy and its effect on cell viability (MTT method), cell morphology (optical microscopy), cell membrane (lactate dehydrogenase release - LDH), oxidative stress pathways (species levels reactive oxygen, ROS and nitrogen, NOS) and apoptosis/necrosis (flow cytometry) were evaluated. RESULTS: The results show that NP CB-EDA at concentrations of 500 and 1000 µg/ml form clusters. The nanoparticle can be absorbed by cells decreasing cell viability. There was damage to the cell membrane of fibroblasts LA 9, an increase in the production of ROS, NOS and pro-inflammatory interleukins TNF-α and IL-6; it was also observed an increase in % of cells in the state of apoptosis in the two periods analyzed, being this response more significant in 24 hours, and concentrations of 250, 500 and 1000 µg/ml presenting higher cytotoxicity. CONCLUSION: The data suggest that NP CB-EDA in fibroblasts LA9 presents cytotoxic potential, which is associated with oxidative stress and apoptosis.

New Multi-Walled carbon nanotube of industrial interest induce cell death in murine fibroblast cells.

The search for new nanomaterials has brought to the multifactorial industry several opportunities for use and applications for existing materials. Carbon nanotubes (CNT), for example, present excellent properties which allow us to assume a series of applications, however there is concern in the industrial scope about possible adverse health effects related to constant exposure for inhalation or direct skin contact. Thus, using cell models is the fastest and safest way to assess the effects of a new material. The aim of this study was to investigate the cytotoxic profile in LA9 murine fibroblast lineage, of a new multi-walled carbon nanotube (MWCNT) that was functionalized with tetraethylenepentamine (TEPA) to obtain better physical-chemical characteristics for industrial use. The modifications presented in the CNT cause concern, as they can change its initial characteristics, making this nanomaterial harmful. HR-TEM, FE-SEM and zeta potential were used for the characterization. Cytotoxicity and cell proliferation tests, oxidative and nitrosative stress analyzes and inflammatory cytokine assay (TNF-α) were performed. The main findings demonstrated a reduction in cell viability, increased release of intracellular ROS, accompanied by an increase in TNF-α, indicating an important inflammatory profile. Confirmation of the data was performed by flow cytometry and ImageXpress with apoptosis/necrosis markers. These data provide initial evidence that OCNT-TEPA has a cytotoxic profile dependent on the concentration of LA9 fibroblasts, since there was an increase in free radicals, inflammation induction and cell death, suggesting that continuous exposure to this nanoparticle can cause damage to different tissues in the organism.

Near-Infrared Photoactive Theragnostic Gold Nanoflowers for Photoacoustic Imaging and Hyperthermia.

Branched anisotropic gold nanostructures present distinguished performance acting both as contrast agents for photoacoustic imaging and as active agents for photothermal therapies. Despite advances in their fabrication methods, the synthesis of such gold nanomaterials in a simple and reproducible way is still a challenge. In this paper, we report the development of branched anisotropic gold nanoparticles, the so-called gold nanoflowers (AuNFs), as near-infrared active theragnostic materials for cancer therapy and diagnosis. In situ chemical synthesis of the AuNFs was optimized to obtain monodisperse nanoflowers with controllable size and optical properties. Upon varying the temperature and gold ion concentrations, it was possible to tune the optical activity of the nanoparticles from 590 to 960 nm. The AuNFs exhibited good stability in the cell culture medium, and under laser irradiation. Photoacoustic imaging revealed that the NFs could be imaged in phantom systems even at low concentrations. In vitro tests revealed that the nanoflowers were effective in the photothermal therapy of a rat hepatocarcinoma (HTC) cell lineage. In addition, no toxicity was observed to mouse fibroblast (FC3H) cells incubated with the AuNFs. Our results reveal a simple method to synthesize branched anisotropic gold nanostructures, which is a promising platform for photothermal and photoacoustic therapies.

Cancer immunosensor based on apo and holo transferrin binding.

An electrochemical immunosensor was developed for the determination of apo-Tf (non-iron-bound) and holo-Tf (iron-bound) using polyclonal antibody transferrin (anti-Tf) immobilized at an electrode surface as a biorecognition platform. The monitoring was based on the anti-Tf binding with both Tf forms which allows the detection of cancer cells due to the constant iron cycle and the overexpression of anti-Tf on the cancer cell surface. The immunosensor characterization was performed using electrochemical impedance spectroscopy (EIS), which evaluated the impedimetric biorecognition of the antigens-antibody by the use of K4Fe(CN)6 redox group. The immunosensor was able to detect both forms of Tf in terms of charge transfer resistance (Rct). Analytical curves showed a limit of detection of 0.049 and 0.053 ng mL-1 for apo-Tf and holo-Tf, respectively. The immunosensor was applied to the detection of the two cancer cells A549 (lung carcinoma) and MCF-7 (breast carcinoma) and compared with BHK570, a healthy cell line. The impedimetric response of healthy cells differs significantly from that of the cancerous cells, as revealed by a Dunnett's test in 95% confidence level-ca. 102 cells mL-1-indicating the feasibility of the immunosensor to discriminate both types of cells. The indirect detection of anti-Tf based on apo-Tf and holo-Tf binding can be considered an advanced approach for cancer recognition. Graphical abstract.

Investigating the interactions of corona-free SWCNTs and cell membrane models using sum-frequency generation.

The understanding of the interactions between biomolecules and nanomaterials is of great importance in many areas of nanomedicine and bioapplications. Numerous studies in this area have been performed. However, toxicological aspects involving the interaction between phospholipids and carbon nanotubes (CNTs) remain undefined, especially for those cases in which a protein corona is not formed around the nanomaterial (corona-free nanomaterials). This study focuses on the interaction of Langmuir films of dipalmitoylphosphatidylglycerol (DPPG) and dipalmitoylphosphatidylcholine (DPPC) with corona-free, single-walled CNTs. Surface pressure-area isotherms and sum-frequency generation (SFG) vibrational spectroscopy, a non-linear optical technique used to study surfaces and interfaces, were used to investigate the lipid tail orientation and conformation, aiming to understand the interactions between phospholipids and single walled carbon nanotubes functionalized by carboxylic acid (SWCNTs-COOH) at the air-water interface under low ionic strength conditions. Data from isotherms and SFG spectra revealed that the SWCNT adsorption at the air-water interface is induced by the presence of both lipids, although at a lesser extent for DPPG due to its anionic head group, which could result in repulsion of SWCNTs-COOH that also bear a negative charge. Furthermore, lipid monolayers remained conformationally ordered, indicating insertion of SWCNTs into the lipid monolayer. Our results corroborate previous works and simulations in the literature, but made it possible to perform an in-depth investigation of the interaction of these nanomaterials with components of phospholipid membranes.

Photothermia and Activated Drug Release of Natural Cell Membrane Coated Plasmonic Gold Nanorods and ß-Lapachone.

Plasmonic gold nanoparticles present extraordinary potential for near-infrared photothermal and triggered-therapeutic release treatments of solid tumors. In this study, we create a multifunctional nanocarrier in which PEG-coated gold nanorods are grouped into natural cell membrane vesicles (CM) from lung cancer (A549) cells and loaded with ß-lapachone (CM-ß-Lap-PEG-AuNRs). ß-Lapachone (ß-Lap) is an anticancer agent activated by the enzyme NADP(H):quinine oxidoreductase (NQO1), commonly found at higher levels in cancer cells. The irradiation with near-infrared (NIR) laser leads to disruption of the vesicles and release of the PEG-AuNRs and ß-Lap. The system presents an enhanced in vitro cytotoxicity against A549 cancer cells, which can be attributed to the specific cytotoxicity of ß-Lap combined with heat generated by laser irradiation of the AuNRs. In agreement, in vivo treatment with CM-ß-Lap-PEG-AuNRs and irradiation shows a histopathological recovery from nonmuscle invasive bladder cancer of most of the animals with only one cycle of application and irradiation. Such multifunctional platform is a promissing candidate for improved activated drug release and phototherapy.

Toxicity of copper oxide nanoparticles to Neotropical species Ceriodaphnia silvestrii and Hyphessobrycon eques.

The increase of production and consumption of copper oxide nanostructures in several areas contributes to their release into aquatic ecosystems. Toxic effects of copper oxide nanoparticles (CuO NPs), in particular, on tropical aquatic organisms are still unknown, representing a risk for biota. In this study, the effects of rod-shaped CuO NPs on the Neotropical species Ceriodaphnia silvestrii and Hyphessobrycon eques were investigated. We also compared the toxicity of CuO NPs and CuCl2 on these species to investigate the contribution of particles and cupper ions to the CuO NPs toxicity. Considering the low copper ions release from CuO NPs (<1%), our results revealed that the toxicity of CuO NPs to C. silvestrii and H. eques was mainly induced by the NPs. The 48 h EC50 for C. silvestrii was 12.6 ±â€¯0.7 µg Cu L-1 and for H. eques the 96 h LC50 was 211.4 ±â€¯57.5 µg Cu L-1 of CuO NPs. There was significant decrease in reproduction, feeding inhibition and increase in reactive oxidative species (ROS) generation in C. silvestrii exposed to CuO NPs. In fish H. eques, sublethal exposure to CuO NPs caused an increase in ROS generation in gill cells and an increase in cells number that were in early apoptotic and necrotic stages. Our results showed that CuO NPs caused toxic effects to C. silvestrii and H. eques and ROS play an important role in the toxicity pathway observed. Data also indicated that C. silvestrii was among the most sensitive species for CuO NPs. Based on predicted environmental concentration in water bodies, CuO NPs pose potential ecological risks for C. silvestrii and H. eques and other tropical freshwater organisms.

An antibody-based platform for melatonin quantification.

Melatonin, the 'chemical signal of darkness', is responsible to regulate biological rhythms and different physiological processes. It is mainly produced by the pineal gland as a hormone in a rhythmic daily basis, but it may also be synthesized by other tissues, such as immune cells, under inflammatory conditions. Its abnormal circulating levels have been related to several diseases such as type 2 diabetes, Alzheimer's disease and some types of cancer. Currently, melatonin is exclusively quantified by ELISA or radioimmunoassays, which although are very sensitive techniques and present low detection limits, usually require specialized personal and equipment, restricting the tests to a limited number of patients. To overcome such limitations, we developed a novel easy-to-use electrochemical immunosensor for rapid melatonin quantification. Anti-melatonin antibodies were immobilized into Indium tin oxide (ITO) platforms using (3-Aminopropyl)triethoxysilane (APTES), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS) crosslinkers. The platforms were assayed with synthetic and biologically-present melatonin containing samples. The developed device displayed a linear response in the concentration range from 0.75 to 7.5 µmol/L and a limit of detection of 0.175 µmol/L using Electrochemical Impedance Spectroscopy (EIS) (R2 = 0.989) and 0.513 µmol/L using Cyclic Voltammetry (CV) (R²â€¯= 0.953) for synthetic melatonin. Furthermore, the sensors exhibited a good stability and reproducibility (3.45% and 2.87% for EIS and CV, respectively, n = 3), maintaining adequate response even after 30 days of assembly. On biologically-present melatonin-containing samples the device displayed a similar performance when compared to ELISA technique (deviation of 13.31%). We expect that the developed device contributes significantly to the medical area allowing precise and complete diagnosis of the diseases related to abnormal levels of melatonin.

Differences in the Aspect Ratio of Gold Nanorods that Induce Defects in Cell Membrane Models.

Understanding the interactions between biomolecules and nanomaterials is of great importance for many areas of nanomedicine and bioapplications. Although studies in this area have been performed, the interactions between cell membranes and nanoparticles are not fully understood. Here, we investigate the interactions that occur between the Langmuir monolayers of dipalmitoylphosphatidyl glycerol (DPPG) and dipalmitoylphosphatidyl choline (DPPC) with gold nanorods (NR)-with three aspect ratios-and gold nanoparticles. Our results showed that the aspect ratio of the NRs influenced the interactions with both monolayers, which suggest that the physical morphology and electrostatic forces govern the interactions in the DPPG-NR system, whereas the van der Waals interactions are predominant in the DPPC-NR systems. Size influences the expansion isotherms in both systems, but the lipid tails remain conformationally ordered upon expansion, which suggests phase separation between the lipids and nanomaterials at the interface. The coexistence of lipid and NP regions affects the elasticity of the monolayer. When there is coexistence between two phases, the elasticity does not reflect the lipid packaging state but depends on the elasticity of the NP islands. Therefore, the results corroborate that nanomaterials influence the packing and the phase behavior of the mimetic cell membranes. For this reason, developing a methodology to understand the membrane-nanomaterial interactions is of great importance.

Synthesis, Physico-Chemical Properties, and Biomedical Applications of Gold Nanorods--A Review.

The development of new systems for diagnostic and therapeutic applications is a topic of intense and growing interest. The unique optical and electronic properties exhibited by gold-based nanomaterials have proved to be valuable for a wide range of biomedical applications. Recently, great attention has been given to rod-shaped gold nanomaterials, especially because of their electronic absorption band in the near infrared region, where maximum radiation penetration through tissue occurs. This feature has allowed the use of gold nanorods for in vivo imaging, with different techniques, and photothermal therapy. Furthermore, gold nanorods can be functionalized with a wide variety of biomolecules for cancer cell targeting. Moreover, their versatility and unique properties have generated much enthusiasm in medicine. The present review aims to show the recent advances in the synthesis and applications of gold nanorods in medical areas.