Ultrabright fluorescent mesoporous silica nanoparticles for prescreening of cervical cancer

Advancements in fluorescent nanobiosensors for HPV detection: from integrating nanomaterials to DNA nanotechnology

Human papillomavirus (HPV) is a leading cause of cervical cancer and other malignancies, necessitating the development of highly sensitive and specific detection tools. This review explores recent advancements in fluorescent nanobiosensors (FNBS) for HPV detection, focusing on the integration of nanomaterials and DNA nanotechnology, highlighting their contributions to improving sensitivity, specificity, and point-of-care (POC) usability. The review critically evaluates a range of nanomaterial-based FNBS, including those employing quantum and carbon dots, nanoclusters, nanosheets, and nanoparticles, discussing their underlying signal amplification mechanisms, target recognition strategies, and limitations related to toxicity, stability, and reproducibility. Furthermore, it examines the application of diverse DNA nanotechnology, such as DNA origami, DNAzyme, catalytic hairpin assembly (CHA), hybridization chain reaction (HCR), and DNA hydrogel in improving FNBS performance. It also addresses the current challenges in clinical translation, emphasizing the necessity for large-scale production methods and thorough clinical validation to ensure biosafety. It also outlines the potential of innovative technologies, such as CRISPR-Cas-based diagnostics and artificial intelligence, to further revolutionize HPV detection and enable accessible, cost-effective screening, particularly in resource-limited settings. This review provides a valuable resource for researchers and clinicians seeking to develop next-generation FNBS for improved HPV diagnostics and cervical cancer prevention.

Recent Advances in HPV Detection: From Traditional Methods to Nanotechnology and the Application of Quantum Dots

Cervical cancer, a significant public health concern, demands precise and expeditious detection methods to curb the spread of human papillomavirus (HPV). The early detection of cervical cancer remains a critical challenge in developing reliable and efficient screening tools to meet the demand for controlling cervical cancer. Traditional detection techniques are often cumbersome, costly, and inadequate for on-site HPV testing. Nanotechnology, with its unique electrical, chemical, and optical properties, has emerged as a pivotal component in the development of biosensors for rapid and reliable HPV detection. This article provides a comprehensive review of the advancements in cervical cancer detection, encompassing traditional methods, emerging protocols, and novel quantum dots (QDs)-based approaches for detection. The review examines the application of various nanomaterials in electrochemical and photoelectrochemical biosensors for the diagnosis of cervical cancer, with these innovations offering a significant improvement over conventional approach. Furthermore, we detail the synthesis methods of QDs and their properties, illustrate the substantial enhancement in sensor performance achieved through their applications, and elucidate the improvements and challenges associated with these new protocols while highlighting the potential application prospects of novel QDs technology in HPV detection.

Ultrabright fluorescent particles via physical encapsulation of fluorescent dyes in mesoporous silica: a mini-review

Harnessing the power of mesoporous silica to encapsulate organic fluorescent dyes has led to the creation of an extraordinary class of nanocomposite photonic materials. These materials stand out for their ability to produce the brightest fluorescent particles known today, surpassing even the luminosity of quantum dots of similar spectrum and size. The synthesis of these materials offers precise control over the shape and size of the particles, ranging from the nano to the multi-micron scale. Just physical encapsulation of the dyes opens new possibilities for mixing different dyes within individual particles, paving the way for nearly limitless multiplexing capabilities. Moreover, this approach lays the groundwork for the development of highly sensitive sensors capable of detecting subtle changes in temperature and acidity at the nanoscale, among other parameters. This mini-review highlights the mechanism of synthesis, explains the nature of ultrabrightness, and describes the recent advancements and future prospects in the field of ultrabright fluorescent mesoporous silica particles, showcasing their potential for various applications.

Nanotechnological Advances in the Diagnosis of Gynecological Cancers and Nanotheranostics

Gynecological cancers are one of the main causes of female mortality worldwide. Despite the various strategies to reduce mortality and improve quality of life, there are still many deficiencies in the diagnosis and treatment of gynecological cancers. One of the important steps to ensure optimal cancer treatment is the early detection of cancer cells and the use of drugs to reduce toxicity. Due to the increase in systemic toxicity and resistance to traditional and conventional diagnostic methods, new strategies, including nanotechnology, are being used to improve diagnosis and reduce the severity of the disease. Nanoparticles (NPs) provide exciting opportunities to improve Gynecological Cancers (GCs) diagnosis, particularly in the initial stages. In biomedical investigations and clinical settings, NPs can be used to increase the sensitivity and specificity of recognition and/or imaging of GCs with the help of their molecular and cellular processes. To design more efficient diagnostic NPs for gynecological cancer cells or tissues, determining the specific biomarkers is of great importance. NP-based imaging agents are another solution to trace cancer cells. This review highlights the potential of some NP-based diagnostic techniques in GC detection, which could be translated to clinical settings to improve patient care.

Towards the Use of Individual Fluorescent Nanoparticles as Ratiometric Sensors: Spectral Robustness of Ultrabright Nanoporous Silica Nanoparticles

Here we address an important roadblock that prevents the use of bright fluorescent nanoparticles as individual ratiometric sensors: the possible variation of fluorescence spectra between individual nanoparticles. Ratiometric measurements using florescent dyes have shown their utility in measuring the spatial distribution of temperature, acidity, and concentration of various ions. However, the dyes have a serious limitation in their use as sensors; namely, their fluorescent spectra can change due to interactions with the surrounding dye. Encapsulation of the d, e in a porous material can solve this issue. Recently, we demonstrated the use of ultrabright nanoporous silica nanoparticles (UNSNP) to measure temperature and acidity. The particles have at least two kinds of encapsulated dyes. Ultrahigh brightness of the particles allows measuring of the signal of interest at the single particle level. However, it raises the problem of spectral variation between particles, which is impossible to control at the nanoscale. Here, we study spectral variations between the UNSNP which have two different encapsulated dyes: rhodamine R6G and RB. The dyes can be used to measure temperature. We synthesized these particles using three different ratios of the dyes. We measured the spectra of individual nanoparticles and compared them with simulations. We observed a rather small variation of fluorescence spectra between individual UNSNP, and the spectra were in very good agreement with the results of our simulations. Thus, one can conclude that individual UNSNP can be used as effective ratiometric sensors.

A Recent Advancement in Nanotechnology Approaches for the Treatment of Cervical Cancer

BACKGROUND

Cervical cancer is one of the leading causes of female death, with a mortality rate of over 200,000 per year in developing countries. Despite a decrease in cervical cancer occurrences in developed countries over the last decade, the frequency of the disease in developing nations continues to rise at an alarming rate, particularly when it is linked to the human papillomavirus (HPV). With just a few highly invasive conventional therapies available, there is a clear need for novel treatment options such as nanotechnology-based chemotherapeutic drug delivery.

METHODS

Traditional anticancer therapy is limited by poor drug potency, non-specificity, unwanted side effects, and the development of multiple drug resistance (MDR), leading to a decrease in long-term anticancer therapeutic efficacy. An ideal cancer therapy requires a personalized and specialized medication delivery method capable of eradicating even the last cancer cell responsible for disease recurrence.

RESULTS

Nanotechnology provides effective drug delivery mechanisms, allowing it to serve both therapeutic and diagnostic purposes. Nanotechnology-based formulations are widely used to accurately target the target organ, maintain drug load bioactivity, preferentially accumulate the drug at the target location, and reduce cytotoxicity.

CONCLUSION

The key benefits of this drug delivery are that it improves pharmacological activity, solubility, and bioavailability and reduces toxicity in the target tissue by targeting ligands, allowing for new innovative treatment methods in an area that is desperately required. The goal of this review is to highlight possible research on nanotechnologybased delivery systems for cancer detection and treatment.

Nanotechnology in cervical cancer immunotherapy: Therapeutic vaccines and adoptive cell therapy

Immunotherapy is an emerging method for the treatment of cervical cancer and is more effective than surgery and radiotherapy, especially for recurrent cervical cancer. However, immunotherapy is limited by adverse effects in clinical practice. In recent years, nanotechnology has been widely used for tumor diagnosis, drug delivery, and targeted therapy. In the setting of cervical cancer, nanotechnology can be used to actively or passively target immunotherapeutic agents to tumor sites, thereby enhancing local drug delivery, reducing drug adverse effects, achieving immunomodulation, improving the tumor immune microenvironment, and optimizing treatment efficacy. In this review, we highlight the current status of therapeutic vaccines and adoptive cell therapy in cervical cancer immunotherapy, as well as the application of lipid carriers, polymeric nanoparticles, inorganic nanoparticles, and exosomes in this context.

Fluorescent silica nanoparticles as an internal marker in fruit flies and their effects on survivorship and fertility

Tracking and differentiating small insects at the individual levels requires appropriate marking materials because of their small size. This study proposes and investigates the use of fluorescent silica nanoparticles (FSNPs) as an internal marker owing to their good optical properties and biocompatibility. FSNPs were prepared using the water-in-oil reverse microemulsion technique with Rubpy dye as a fluorophore. The obtained particles were spherical, monodispersed in nanosize and exhibited bright orange luminescence under ultraviolet (UV) light. Internal marking was accomplished in fruit flies (Drosophila melanogaster) through feeding. The result shows that the fruit flies exhibit bright luminescence in their abdomen when exposed to UV light. The marking persistence duration of FSNPs in the fruit fly bodies is longer than those of other fluorescent dyes. Fruit flies fed with FSNPs have a longer lifespan than those fed with Rubpy dye. There was no difference in fertility and negative geotaxis response among the treatment and control groups. These findings demonstrate that FSNPs can be used as an internal marker in fruit flies, and are possibly applied with other small insects with a translucent abdomen.

An Update on Mesoporous Silica Nanoparticle Applications in Nanomedicine

The efficient and safe delivery of therapeutic drugs, proteins, and nucleic acids are essential for meaningful therapeutic benefits. The field of nanomedicine shows promising implications in the development of therapeutics by delivering diagnostic and therapeutic compounds. Nanomedicine development has led to significant advances in the design and engineering of nanocarrier systems with supra-molecular structures. Smart mesoporous silica nanoparticles (MSNs), with excellent biocompatibility, tunable physicochemical properties, and site-specific functionalization, offer efficient and high loading capacity as well as robust and targeted delivery of a variety of payloads in a controlled fashion. Such unique nanocarriers should have great potential for challenging biomedical applications, such as tissue engineering, bioimaging techniques, stem cell research, and cancer therapies. However, in vivo applications of these nanocarriers should be further validated before clinical translation. To this end, this review begins with a brief introduction of MSNs properties, targeted drug delivery, and controlled release with a particular emphasis on their most recent diagnostic and therapeutic applications.

Zebrafish Models for the Safety and Therapeutic Testing of Nanoparticles with a Focus on Macrophages

New nanoparticles and biomaterials are increasingly being used in biomedical research for drug delivery, diagnostic applications, or vaccines, and they are also present in numerous commercial products, in the environment and workplaces. Thus, the evaluation of the safety and possible therapeutic application of these nanomaterials has become of foremost importance for the proper progress of nanotechnology. Due to economical and ethical issues, in vitro and in vivo methods are encouraged for the testing of new compounds and/or nanoparticles, however in vivo models are still needed. In this scenario, zebrafish (Danio rerio) has demonstrated potential for toxicological and pharmacological screenings. Zebrafish presents an innate immune system, from early developmental stages, with conserved macrophage phenotypes and functions with respect to humans. This fact, combined with the transparency of zebrafish, the availability of models with fluorescently labelled macrophages, as well as a broad variety of disease models offers great possibilities for the testing of new nanoparticles. Thus, with a particular focus on macrophage-nanoparticle interaction in vivo, here, we review the studies using zebrafish for toxicological and biodistribution testing of nanoparticles, and also the possibilities for their preclinical evaluation in various diseases, including cancer and autoimmune, neuroinflammatory, and infectious diseases.

Recent Trends in Morphology-Controlled Synthesis and Application of Mesoporous Silica Nanoparticles

The outstanding journey towards the investigation of mesoporous materials commences with the discovery of high surface area porous silica materials, named MCM-41 (Mobil Composition of Matter-41) according to the inventors' name Mobile scientists in the United States. Based on a self-assembled supramolecular templating mechanism, the synthesis of mesoporous silica has extended to wide varieties of silica categories along with versatile applications of all these types in many fields. These silica families have some extraordinary structural features, like highly tunable nanoscale sized pore diameter, good Brunauer-Emmett-Teller (BET) surface areas, good flexibility to accommodate different organic and inorganic functional groups, metals etc., onto their surface. As a consequence, thousands of scientists and researchers throughout the world have reported numerous silica materials in the form of published articles, communication, reviews, etc. Beside this, attention is also given to the morphology-oriented synthesis of silica nanoparticles and their significant effects on the emerging fields of study like catalysis, energy applications, sensing, environmental, and biomedical research. This review highlights a consolidated overview of those morphology-based mesoporous silica particles, emphasizing their syntheses and potential role in many promising fields of research.

Ultrabright Fluorescent Silica Nanoparticles for Multiplexed Detection

Fluorescent tagging is a popular method in biomedical research. Using multiple taggants of different but resolvable fluorescent spectra simultaneously (multiplexing), it is possible to obtain more comprehensive and faster information about various biochemical reactions and diseases, for example, in the method of flow cytometry. Here we report on a first demonstration of the synthesis of ultrabright fluorescent silica nanoporous nanoparticles (Star-dots), which have a large number of complex fluorescence spectra suitable for multiplexed applications. The spectra are obtained via simple physical mixing of different commercially available fluorescent dyes in a synthesizing bath. The resulting particles contain dye molecules encapsulated inside of cylindrical nanochannels of the silica matrix. The distance between the dye molecules is sufficiently small to attain Forster resonance energy transfer (FRET) coupling within a portion of the encapsulated dye molecules. As a result, one can have particles of multiple spectra that can be excited with just one wavelength. We show this for the mixing of five, three, and two dyes. Furthermore, the dyes can be mixed inside of particles in different proportions. This brings another dimension in the complexity of the obtained spectra and makes the number of different resolvable spectra practically unlimited. We demonstrate that the spectra obtained by different mixing of just two dyes inside of each particle can be easily distinguished by using a linear decomposition method. As a practical example, the errors of demultiplexing are measured when sets of a hundred particles are used for tagging.

In Vivo Targeting of Xenografted Human Cancer Cells with Functionalized Fluorescent Silica Nanoparticles in Zebrafish

Developing nanoparticles capable of detecting, targeting, and destroying cancer cells is of great interest in the field of nanomedicine. In vivo animal models are required for bridging the nanotechnology to its biomedical application. The mouse represents the traditional animal model for preclinical testing; however, mice are relatively expensive to keep and have long experimental cycles due to the limited progeny from each mother. The zebrafish has emerged as a powerful model system for developmental and biomedical research, including cancer research. In particular, due to its optical transparency and rapid development, zebrafish embryos are well suited for real-time in vivo monitoring of the behavior of cancer cells and their interactions with their microenvironment. This method was developed to sequentially introduce human cancer cells and functionalized nanoparticles in transparent Casper zebrafish embryos and monitor in vivo recognition and targeting of the cancer cells by nanoparticles in real time. This optimized protocol shows that fluorescently labeled nanoparticles, which are functionalized with folate groups, can specifically recognize and target metastatic human cervical epithelial cancer cells labeled with a different fluorochrome. The recognition and targeting process can occur as early as 30 min postinjection of the nanoparticles tested. The whole experiment only requires the breeding of a few pairs of adult fish and takes less than 4 days to complete. Moreover, zebrafish embryos lack a functional adaptive immune system, allowing the engraftment of a wide range of human cancer cells. Hence, the utility of the protocol described here enables the testing of nanoparticles on various types of human cancer cells, facilitating the selection of optimal nanoparticles in each specific cancer context for future testing in mammals and the clinic.

Ultrabright fluorescent silica nanoparticles for in vivo targeting of xenografted human tumors and cancer cells in zebrafish

New ultrabright fluorescent silica nanoparticles capable of the fast targeting of epithelial tumors in vivo are presented. The as-synthesized folate-functionalized ultrabright particles of 30-40 nm are 230 times brighter than quantum dots (QD450) and 50% brighter than the polymer dots with similar spectra (excitation 365 nm and emission 486 nm). To decrease non-specific targeting, particles are coated with polyethylene glycol (PEG). We demonstrate the in vivo targeting of xenographic human cervical epithelial tumors (HeLa cells) using zebrafish as a model system. The particles target tumors (and probably even individual HeLa cells) as small as 10-20 microns within 20-30 minutes after blood injection. To demonstrate the advantages of ultrabrightness, we repeated the experiments with similar but 200× less bright particles. Compared to those, ultrabright particles showed ∼3× faster tumor detection and ∼2× higher relative fluorescent contrast of tumors/cancer cells.

Folate-conjugated nanovehicles: Strategies for cancer therapy

Cancer theranostics represents a strategy that aims at combining diagnosis with therapy through the simultaneous imaging and targeted delivery of therapeutics to cancer cells. Recently, the folate receptor alpha has emerged as an attractive theranostic target due to its overexpression in multiple solid tumors and its great functional versatility. In fact, it can be incorporated into folate-conjugated nano-systems for imaging and drug delivery. Hence, it can be used along the line of personalized clinical strategies as both an imaging tool and a delivery method ensuring the selective transport of treatments to tumor cells, thus highlighting its theranostic qualities. In this review, we will explore these theranostic characteristics in detail and assess their clinical potential. We will also discuss the technological advances that have allowed the design of sophisticated folate-based nanocarriers harboring various chemical properties and suited for the transport of various therapeutic agents.

Ultrabright dye-loaded spherical polyelectrolyte brushes and their fundamental structure-fluorescence tuning principles

Ultrabright fluorescent particles (UFPs) have attracted increasing attention because of their outstanding signal amplification functions. However, there is still an urgent demand for designing novel UFPs with new components or structures as the existing ones can not satisfy the practical requirements due to their inherent disadvantages. Here we propose a novel ultrabright fluorescent particle platform by doping dyes of 5-aminofluorescein (5-AF) into silica core-based spherical poly (acrylic acid) brushes (SiO₂@PAA@5-AF) and discuss their fundamental structure-fluorescence tuning principles. A series of brushes with different polymer chain lengths are successfully synthesized and then loaded with 5-AF through chemical binding. The high loading amount, suitable density or distribution, and enhanced quantum yield (QY) of 5-AF due to the amide bond formation with PAA chains on brushes are concluded as the three major reasons for the ultrabrightness of SiO₂@PAA@5-AF. Therefore, a 2350 ± 445 times brighter brush particle in comparison to a single quantum dot (QD) is realized, and a 2.1 ± 0.4 times fluorescence improvement of a brush vs. a QD normalized by volume is also achieved when taking the hydrodynamic diameter into consideration (∼300 nm vs. ∼30 nm). Moreover, the excellent tolerance stabilities in normally applied environments and outstanding label effects to form 4-plexed encoded beads are demonstrated as well. The results in this work strongly indicate a promising potential of SiO₂@PAA@5-AF as an ultrabright and stable signal amplification tool for biomedical related sensing, labeling, and biodetection.

Early detection of cervical cancer based on high-risk HPV DNA-based genosensors: A systematic review

Human papillomavirus type (HPV) is a common cause of sexually transmitted disease (STD) in humans. HPV types 16 and 18 as the highest risk types are related with gynecologic malignancy and cervical cancer (CC) among women worldwide. Recently, considerable development of genosensors, which allows dynamic monitoring of hybridization events for HPV-16 and 18, has been a topic of focus by many researchers. In this systematic review, we highlight the route of development of DNA-based genosensory detection methods for diagnosis of high risk of HPV precancer. Biosensor detection methods of HPV-16 and 18 was investigated from 1994 to 2018 using several databases including PubMed, Cochrane Library, Scopus, Google Scholar, SID, and Scientific Information Database. Manual search of references of retrieved articles were also performed. A total of 50 studies were reviewed. By analyzing the most recent developed electrochemical biosensors for the identification of HPV, we observed that the sensor platform fabricated by Wang et al. holds the lowest detection limit reported in the literature for the DNA of HPV-16. Up to this date, optical, electrochemical, and piezoelectric systems are the main transducers used in the development of biosensors. Among the most sensitive techniques available to study the biorecognition activity of the sensors, we highlight the biosensors based fluorescent, EIS, and QCM. The current systematic review focuses on the sensory diagnostic methods that are being used to detect HPV-16 and 18 worldwide. Special emphasis is given on the sensory techniques that can diagnosis the individuals with CC. © 2018 BioFactors, 45(2):101-117, 2019.

The Bioimaging Applications of Mesoporous Silica Nanoparticles

The unique features of Mesoporous Silica Nanoparticles (MSNs) provide a suitable platform to carry fluorescence dyes for various bioimaging applications. Several strategies have been developed to conjugate a variety of dyes either in the pores or on the surfaces of MSNs to form the fluorescence MSNs (FMSNs). In this chapter, we will discuss recent research progress and future development of FMSNs for living system imaging. We will first describe different strategies for the fabrications of FMSNs. Then, we will discuss the recent developments of cellular and intracellular imaging including self-probe for the interactions of FMSNs with the cells, receptor and organelle labeling, sensing and tracking of biological system, and monitoring the drug delivery and release processes. Moreover, we will include the applications of FMSNs as contrast agents for in vivo imaging. Finally, we will conclude and highlight the challenges and opportunities for MSNs in medical applications.

Nanomedicine applications in women's health: state of the art

State-of-the-art applications of nanomedicine have the potential to revolutionize the diagnosis, prevention, and treatment of a range of conditions and diseases affecting women’s health. In this review, we provide a synopsis of potential applications of nanomedicine in some of the most dominant fields of women’s health: mental health, sexual health, reproductive medicine, oncology, menopause-related conditions and dementia. We explore published studies arising from in vitro and in vivo experiments, and clinical trials where available, to reveal novel and highly promising therapeutic applications of nanomedicine in these fields. For the first time, we summarize the growing body of evidence relating to the use of nanomaterials as experimental tools for the detection, prevention, and treatment of significant diseases and conditions across the life course of a cisgender woman, from puberty to menopause; revealing the far-reaching and desirable theoretical impact of nanomedicine across different medical disciplines. We also present an overview of potential concerns regarding the therapeutic applications of nanomedicine and the factors currently restricting the growth of applied nanomedicine.

Ultrabright fluorescent silica particles with a large number of complex spectra excited with a single wavelength for multiplex applications

We report on a novel approach to synthesize ultrabright fluorescent silica particles capable of producing a large number of complex spectra. The spectra can be excited using a single wavelength which is paramount in quantitative fluorescence imaging, flow cytometry and sensing applications. The approach employs the physical encapsulation of organic fluorescent molecules inside a nanoporous silica matrix with no dye leakage. As was recently demonstrated, such an encapsulation allowed for the encapsulation of very high concentrations of organic dyes without quenching their fluorescent efficiency. As a result, dye molecules are distanced within ∼5 nm from each other; it theoretically allows for efficient exchange of excitation energy via Förster resonance energy transfer (FRET). Here we present the first experimental demonstration of the encapsulation of fluorescent dyes in the FRET sequence. Attaining a FRET sequence of up to five different dyes is presented. The number of distinguishable spectra can be further increased by using different relative concentrations of encapsulated dyes. Combining these approaches allows for creating a large number of ultrabright fluorescent particles with substantially different fluorescence spectra. We also demonstrate the utilization of these particles for potential multiplexing applications. Though fluorescence spectra of the obtained multiplex probes are typically overlapping, they can be distinguished by using standard linear decomposition algorithms.

Ru(bpy)2(phen-5-NH2)2+ doped ultrabright and photostable fluorescent silica nanoparticles

Ru(bpy)₂(phen-5-NH₂)²⁺ doped silica nanoparticles with high fluorescence brightness and controllable size are synthesized via reverse microemulsion method by introducing ethanol to reaction system.

Cytotoxicity of multifunctional surfactant containing capped mesoporous silica nanoparticles

This paper reports the synthesis of silica capped surfactant (CTAB) and dye (Rose Bengal; RB) containing mesoporous silica nanoparticles (MSNs).

Ultrabright NIR fluorescent mesoporous silica nanoparticles

Near-infrared (NIR) water-dispersible fluorescent tags are of big importance for biomedical imaging. Bright, stable, biocompatible NIR fluorescent nanoparticles have great translation potential to improve diagnosis of early stages of different diseases. Here we report on the synthesis of exceptionally bright ("ultrabright") fluorescent meso(nano)porous silica nanoparticles of 28 ± 3 nm in diameter. The NIR fluorescent dye LS277 is encapsulated inside these silica nanoparticles. The wavelengths of the maximum excitation/fluorescence of the particles are 804/815 nm. The absorptivity coefficient of the particles is 2.1 × 10⁸ M^-1 cm^-1 at 805 nm and the quantum yield of the dye increased by a factor of 5 after encapsulating to 1.5%. The fluorescent brightness of these particles is more than 2000× higher than the fluorescence of one molecule of LS277 in water. When exited in NIR spectral region (>700 nm), these particles are up to 4× brighter than QD800 commercial quantum dots emitting at 800 nm. We demonstrate that the synthesized NIR mesoporous silica nanoparticles easily internalize 4T1luc breast tumor cells, and remain bright for more than 9 weeks whereas the dye is completely bleached by that time.

Ultrabright fluorescent mesoporous silica nanoparticles for prescreening of cervical cancer

We report on the first functional use of recently introduced ultrabright fluorescent mesoporous silica nanoparticles, which are functionalized with folic acid, to distinguish cancerous and precancerous cervical epithelial cells from normal cells. The high brightness of the particles is advantageous for fast and reliable identification of both precancerous and cancerous cells. Normal and cancer cells were isolated from three healthy women and three cancer patients. Three precancerous cell lines were derived by immortalization of primary cultures of normal cells with human papillomavirus type-16 (HPV-16) DNA. We observed substantially different particle internalization by normal and cancerous/precancerous cells after a short incubation time of 15 minutes. Compared to HPV-DNA and cell pathology tests, which are currently used for prescreening of cervical cancer, we demonstrated that the specificity of our method was similar (94-95%), whereas its sensitivity was significantly better (95-97%) than the sensitivity of those currently used tests (30-80%).

FROM THE CLINICAL EDITOR

This team of investigators reports on the development of a new screening test for cervical cancer using ultrabright fluorescent mesoporous silica nanoparticles functionalized with folic acid, enabling significantly better sensitivity (95-97% vs. 30-80%) and maintained specificity (94-95%) compared with current clinical tests. This test should find a way to clinical use in the near future.