Sweat Samples Research Articles

Hydrophilic metal-organic frameworks integrated uricase for wearable detection of sweat uric acid

The chemistry of the metal-organic frameworks (MOFs) coating may affect the biological functionality of the encapsulated biomacromolecules in harsh environment. Enzymes encapsulated in hydrophilic MAF-7 can retain high activity in harsh environment. We conducted this study to prepare a non-invasive wearable uircase@MAF-7-based electrochemical sensor that can achieve accurate and sensitive detection of UA levels in sweat by integrating a flexible microfluidic chip and wireless electronic readout device. The flexible microfluidic chip enabled an easy and effective collection of sweat samples. MAF-7 protected enzyme activity by encapsulating uricase. The uricase@MAF-7-based electrochemical sensor enabled the highly sensitive detection of UA in the concentration range of 2 μM–70 μM with a detection limit of as low as 0.34 μM. Additionally, we evaluated the utility of the sensor for monitoring UA levels in real sweat samples by means of a high purine dietary challenge. This personalized wearable sweat sensing device has a potential to be used for monitoring disease-related metabolites in daily life.

A novel colorimetric method for H2O2 sensing and its application: Fe2+-catalyzed H2O2 prevents aggregation of AuNPs by oxidizing cysteine (FeHOAuC)

The inhibition of hydrogen peroxide (H2O2) on the cysteine-mediated aggregation of gold nanoparticles (AuNPs) has great potential to rapidly visualize H2O2 and disease-associated biomarkers. However, associated applications have been rigid due to the low cysteine-oxidation efficiency or the insufficient interference-resistance of previous catalysts. Here, we proposed a novel AuNPs colorimetric method termed Fe2+-catalyzed H2O2-preventing aggregation of AuNPs by oxidizing Cysteine (FeHOAuC) for the visible and rapid detection of H2O2 with high specificity. Formed Fe2+-cysteine composites in the beginning, Fe2+ accelerates the oxidation of cysteine by H2O2 with an intramolecular electron-transferring model, and the generated cysteine oxides (including cysteic acid or cystine, dependent on the ratio of cysteine to H2O2 molecules) lose the pro-aggregation effect on AuNPs. Notably, FeHOAuC can quantify 2–30 μM of H2O2 within 5 min, and the monitoring process works well with tolerance to the impact of dissolved oxygen. The FeHOAuC paired with lactate oxidase was successfully used for measuring lactic acids in real sweat samples with a practicable detection window (2–60 μM) and a low variable coefficient (<10%). In summary, FeHOAuC is a feasible platform for rapid and convenient detection of H2O2 and oxidase-specific substrates.

Sensitive enzymatic determination of neurotransmitters in artificial sweat

Dopamine (DA) and epinephrine (EN) are two phenolic molecules that are used in the human body and secreted in the brain actuating as neurotransmitters. As both molecules are highly important in the brain and the central nervous system, monitoring of their concentrations would enable better understanding of their importance and role in different physiological conditions. Copper efflux oxidase from Escherichia coli was shown in the past to have the ability of oxidizing polyphenolic compounds. As such, we have engineered this enzyme for its site-specific attachment to an electrode for the detection of DA and EN in high resolution and sensitivity. Here we present an enzymatic biosensor that enables the detection of such molecules with a 10 nM resolution and a linear range of up to 100 nM in artificial sweat samples. The presented biosensor could be used for the determination of catecholamines in different bodily fluids.

Excretion of Ni, Pb, Cu, As, and Hg in Sweat under Two Sweating Conditions.

Physiologists have long regarded sweating as an effective and safe means of detoxification, and heavy metals are excreted through sweat to reduce the levels of such metals in the body. However, the body can sweat through many means. To elucidate the difference in the excretion of heavy metals among sweating methods, 12 healthy young university students were recruited as participants (6 men and 6 women). Sweat samples were collected from the participants while they were either running on a treadmill or sitting in a sauna cabinet. After they experienced continuous sweating for 20 min, a minimum of 7 mL of sweat was collected from each participant, and the concentrations of nickel (Ni), lead (Pb), copper (Cu), arsenic (As), and mercury (Hg) were analyzed. The results demonstrated that the sweating method affected the excretion of heavy metals in sweat, with the concentrations of Ni, Pb, Cu, and As being significantly higher during dynamic exercise than during sitting in the sauna (all p < 0.05). However, the concentrations of Hg were unaffected by the sweating method. This study suggests that the removal of heavy metals from the body through dynamic exercise may be more effective than removal through static exposure to a hot environment.

Skin microbiota diversity among genetically unrelated individuals of Indian origin.

BackgroundHuman skin harbors complex transient and resident microbial communities that show intra- & inter-individual variation due to various environmental and host-associated factors such as skin site, diet, age, gender, genetics, or the type and use of cosmetics. This variation remains largely uncharacterized in the Indian population; hence, the present study aims to characterize the variation in skin microbiota among individuals of Indian origin and quantify associations with age, diet, and geography.MethodsAxillary sweat samples from genetically unrelated individuals (N = 58) residing in the three geographical locations of Maharashtra, India, were collected using a sterile cotton swab. Bacterial DNA was extracted using a standard protocol and checked for quality. Variable regions (V3–V4) of the 16S rRNA gene were sequenced using the Illumina platform. We used standard methods from microbiota bioinformatics, including alpha and beta diversity, community typing, and differential abundance, to quantify the association of skin microbiota with age, diet, and geographical location.ResultsOur study indicated the prevalence of phyla- Firmicutes, Proteobacteria, and Actinobacteria, consistent with previous reports on skin microbiota composition of the world population level. The alpha diversity (Shannon index) was significantly associated with the age group (Kruskal–Wallis test, p = 0.02), but not with geography (p = 0.62) or diet (p = 0.74). The overall skin microbiota community composition was significantly associated with geographical location based on Community State Types (CST) analysis and PERMANOVA (R2 = 0.07, p = 0.01). Differential abundance analysis at the genus level indicated a distinctively high abundance of Staphylococcus and Corynebacterium among individuals of the Pune district. Pseudomonas and Anaerococcus were abundant in individuals from Ahmednagar whereas, Paenibacillus, Geobacillus, Virgibacillus, Jeotgalicoccus, Pullulanibacillus, Delsulfosporomusa, Citinovibrio, and Calditerricola were abundant in individuals from Nashik district.ConclusionOur work provides one of the first characterizations of skin microbiota variation in different sub-populations in India. The analysis quantifies the level of individuality, as contrasted to the other factors of age, geography, and diet, thus helping to evaluate the applicability of skin microbiota profiles as a potential biomarker to stratify individuals.

Lab-on-cloth integrated with a photoelectrochemical cell and ion imprinting for point-of-care testing of Hg(Ⅱ)

In this work, we successfully developed a cloth-based device integrated with a photoelectrochemical (PEC) cell and ion imprinting for point-of-care testing (POCT) of divalent mercury ions (Hg(Ⅱ)). PEC cells have increasingly emerged as promising power supply units in recent years. The CdS/ZnS core-shell quantum dots (QDs) are used in the PEC cell, because they improve the spatial separation and transfer of charge and broaden the absorption of visible light. Ion imprinting can identify a specific metal ion selectively in the presence of other interfering ions. To achieve noninterference identification, the QDs-based PEC cell region is isolated from the ion imprinting-based detection area. In addition, wax screen-printing can be used in conjunction with carbon ink screen-printing for economical and facile fabrication of cloth-based devices. Under optimized conditions, Hg(Ⅱ) can be determined over the range of 0.0005–5 mg/L, with a detection limit of 0.090 µg/L (i.e., 0.45 nM). The proposed cloth-based devices are also applied successfully for the detection of Hg(Ⅱ) in sweat, complex water and food samples, with recoveries of 98.2–116.1% and relative standard deviations (RSDs) of 1.2–13.9%. Additionally, cloth-based devices have acceptable storage stability and selectivity. Therefore, the presented method offers a sensitive, low-cost, portable POCT device and has the potential to be applied for human body, environmental and food monitoring in remote areas and developing or industrialized countries.

A Wearable PVA Film Supported TiO2 Nanoparticles Decorated NaNbO3 Nanoflakes‐Based SERS Sensor for Simultaneous Detection of Metabolites and Biomolecules in Human Sweat Samples

AbstractSweat is one of the non‐invasive diagnostic biofluids that provides critical information about human health. In this work, a wearable sweat sensor integrated with a polymer‐based fluid absorption layer modified with titanium oxide (TiO2) nanoparticles decorated sodium niobate (NaNbO3) nanoflakes in porous polyvinyl alcohol (PVA) film matrix is demonstrated for the detection of vital metabolites (such as glucose and urea) and biomolecules (ascorbic acid (AA) and uric acid (UA)) in human sweat samples via surface‐enhanced Raman scattering (SERS). The TiO2@NaNbO3/PVA (SERS patch) exhibits a low limit of detection (LOD) of 0.50, 0.80, 1.00, and 100 mm towards AA, glucose, UA, and urea, respectively. The SERS patch displays a high enhancement factor with a low accumulation time of 20s which can be ascribed to the surface coordination between the TiO2@NaNbO3 and the analytes leading to interfacial charge‐transfer transition (ICTT). Besides, the photo‐induced charge transfer (PICT) resonance significantly amplifies the SERS signal. The SERS patch is successful in the simultaneous determination of AA, glucose, UA, and urea in simulated sweat samples with minimal mutual interference. The high efficacy of the SERS patch proves it as an ideal platform for a wide range of wearable healthcare monitoring applications.

MXene nanoflakes decorating ZnO tetrapods for enhanced performance of skin-attachable stretchable enzymatic electrochemical glucose sensor

Continuous painless glucose monitoring is the greatest desire of more than 422 million diabetics worldwide. Therefore, new non-invasive and convenient approaches to glucose monitoring are more in demand than other tests for microanalytical diagnostic tools. Besides, blood glucose detection can be replaced by continuous glucose monitoring of other human biological fluids (e.g. sweat) collected non-invasively. In this study, a skin-attachable and stretchable electrochemical enzymatic sensor based on ZnO tetrapods (TPs) and a new class of 2D materials - transition metal carbides, known as MXene, was developed and their electroanalytical behavior was tailored for continuous detection glucose in sweat. The high specific area of ZnO TPs and superior electrical conductivity of MXene (Ti3C2Tx) nanoflakes enabled to produce enzymatic electrochemical glucose biosensor with enhanced sensitivity in sweat sample (29 μA mM−1 cm−2), low limit of detection (LOD ≈ 17 μM), broad linear detection range (LDR = 0.05–0.7 mM) that satisfices glucose detection application in human sweat, and advanced mechanical stability (up to 30% stretching) of the template. The developed skin-attachable stretchable electrochemical electrodes allowed to monitor the level of glucose in sweat while sugar uptake and during physical activity. Continuous in vivo monitoring of glucose in sweat obtained during 60 min correlated well with data collected by a conventional amperometric blood glucometer in vitro mode. Our findings demonstrate the high potential of developed ZnO/MXene skin-attachable stretchable sensors for biomedical applications on a daily basis.

A Portable 3D Microfluidic Origami Biosensor for Cortisol Detection in Human Sweat.

Analysis of cortisol levels in human sweat is increasingly important as it can be a "stress biomarker" in stress-related disorders, giving real-time information about human health status. In this study, a portable 3D microfluidic origami biosensor based on a smartphone was developed for cortisol-level detection in human sweat. Molybdenum disulfide (MoS2) nanosheet-mediated fluorescence resonance energy transfer (FRET) and fluorescently labeled aptamers were employed in the biosensing process. A multilayer-structured 3D origami microfluidic chip was fabricated and functionalized to facilitate low-volume perspired human sweat collection, transportation, and detection. The translatability of the biosensor was exhibited by the fluorescence analysis in a smartphone mounted in a custom-designed holder. The critical design parameters of the microfluidic origami biosensor, including the characterization of various paper substrates, the concentration of MoS2 nanosheets, and the incubation/reaction time, were adjusted to obtain an acceptable range for the assay dynamic range and limit of detection (LOD). Under optimum conditions, various doses of cortisol within the physiologically relevant range of 10-1000 ng/mL reported in human sweat were tested to evaluate the performance of the proposed biosensor. It displayed an LOD of 6.76 ng/mL at 3σ in artificial sweat, an analysis time of 25 min, and high selectivity. The performance of the proposed cortisol sensor was compared with an enzyme-linked immunosorbent assay (ELISA) for a spiked artificial sweat sample, and a correlation coefficient of 0.988 was found. The proposed biosensor also presented satisfactory results in the determination of the cortisol levels in a real human sweat sample. The resulting portable biosensor provides a rapid, low-cost, convenient, and non-invasive sensing solution for the point-of-care analysis of cortisol levels in sweat.

Identifying SARS-COV-2 infected patients through canine olfactive detection on axillary sweat samples; study of observed sensitivities and specificities within a group of trained dogs.

There is an increasing need for rapid, reliable, non-invasive, and inexpensive mass testing methods as the global COVID-19 pandemic continues. Detection dogs could be a possible solution to identify individuals infected with SARS-CoV-2. Previous studies have shown that dogs can detect SARS-CoV-2 on sweat samples. This study aims to establish the dogs’ sensitivity (true positive rate) which measures the proportion of people with COVID-19 that are correctly identified, and specificity (true negative rate) which measures the proportion of people without COVID-19 that are correctly identified. Seven search and rescue dogs were tested using a total of 218 axillary sweat samples (62 positive and 156 negative) in olfaction cones following a randomised and double-blind protocol. Sensitivity ranged from 87% to 94%, and specificity ranged from 78% to 92%, with four dogs over 90%. These results were used to calculate the positive predictive value and negative predictive value for each dog for different infection probabilities (how likely it is for an individual to be SARS-CoV-2 positive), ranging from 10–50%. These results were compared with a reference diagnostic tool which has 95% specificity and sensitivity. Negative predictive values for six dogs ranged from ≥98% at 10% infection probability to ≥88% at 50% infection probability compared with the reference tool which ranged from 99% to 95%. Positive predictive values ranged from ≥40% at 10% infection probability to ≥80% at 50% infection probability compared with the reference tool which ranged from 68% to 95%. This study confirms previous results, suggesting that dogs could play an important role in mass-testing situations. Future challenges include optimal training methods and standardisation for large numbers of detection dogs and infrastructure supporting their deployment.

Wearable glove-embedded sensors for therapeutic drug monitoring in sweat for personalized medicine

Wearable sensing technology may fulfill the requirements of precision medicine, but the use of on-body devices for rapid, selective screening of therapeutic drugs is relatively new. In this paper, we report on wearable glove-embedded sensors for non-invasive and selective determination of therapeutic drugs and a biomarker in sweat samples. Electrochemical sensing was made with an array of sensors printed on four fingers of a plastic glove. Uric acid was detected using the index finger functionalized with carbon black with a limit of detection of 1.37 × 10–6 mol L–1. Paracetamol and paroxetine were detected using the middle and ring fingers coated with Printex Carbon with limits of detection of 2.47 × 10–7 and 4.93 × 10–7 mol L–1, respectively. Ethinylestradiol (EE2) detection was performed with a pre-treated screen-printed carbon electrode on the little finger with limit of detection of 9.35 × 10–7 mol L–1. The high sensitivity and selectivity achieved with the glove-embedded sensors were possible due to a judicious choice of sensing layers and optimized working conditions for differential pulse voltammetry. Monitoring of the analytes was carried out in sweat samples with suitable recovery between 90 and 110%. The glove-embedded sensors were robust against multiple flexion cycles, stable and reproducible, with no response to interference from other molecules in sweat. They may be extended to detect other targets for on-site analysis, in addition to applications in environmental and water samples.

Progress in wearable sweat sensors and their applications

Wearable sweat sensors combine the benefits of noninvasive sweat sampling and wearable real-time measurement, providing a powerful platform for monitoring a wealth of biochemical components of sweat related to physiological conditions. The recent progress of wearable sweat sensors is attributed to the rapid development of interdisciplinary research among material science, manufacturing technology, and advanced electronics field. This review focuses on the construction of wearable sweat sensors, especially the design of a flexible sensing interface and integrated wearable sweat sensor. In addition, we outline the extensive applications of wearable sweat sensors from healthcare and sports monitoring to biofuel cells. Finally, several issues and opportunities of future wearable sweat sensors are discussed.

Wearable Potentiometric Sensor Based on Na0.44MnO2 for Non-invasive Monitoring of Sodium Ions in Sweat.

Here, we present a wearable potentiometric ion sensor for real-time monitoring of sodium ions (Na+) in human sweat samples using Na0.44MnO2 as the sensing material. Na0.44MnO2 is an attractive material for developing wearable electrochemical sensors due to its good Na+ incorporation ability, electrical conductivity, stability, and low fabrication cost. In the first step, the analytical performance of the electrode prepared using Na0.44MnO2 is presented. Then, a miniaturized potentiometric cell integrated into a wearable substrate is developed, which reveals a Nernstian response (58 mV dec-1). We achieved the detection of Na+ in the linear ranges of 0.21-24.54 mmol L-1, which is well within the physiological range of Na+. Finally, for on-body sweat analysis, the potentiometric sensor is fully integrated into a headband textile. This platform can be employed for non-invasive analysis of Na+ in human sweat for healthcare and disease diagnosis.

Design and fabrication of novel flexible sensor based on 2D Ni-MOF nanosheets as a preliminary step toward wearable sensor for onsite Ni (II) ions detection in biological and environmental samples

Herein, for the first time, an innovative and sensitive flexible sensor for efficient potentiometric monitoring of Ni (II) ions has been designed and developed. The developed flexible sensor is constructed from highly porous activated flexible carbon cloth decorated with nitrogen and spherical porous carbon nanoparticles derived from low-cost cotton doped with polypyrrole nanoparticles via simple carbonization-activation process followed by dip-coating in membrane cocktail containing 2D Ni-MOF nanosheets as an electroactive material. The developed flexible sensor affords rapid, accurate and stable response for the Ni (II) ions monitoring at its trace level in the biological fluids including human saliva and sweat samples in addition to tap water as an environmental sample without any preconditioning steps over pH range of 2–8 with detection limit of 2.7 × 10−6. Additionally, the flexible sensor shows good antibacterial properties against both of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria presenting safe handling for human skin as a flexible sensor for wearable system applications. This study presents a forward step for the fabrication of a wearable sensor for rapid onsite monitoring of Ni (II) ions in biological and environmental samples.

Colorimetric and Electrochemical Screening for Early Detection of Diabetes Mellitus and Diabetic Retinopathy-Application of Sensor Arrays and Machine Learning.

In this review, a selection of works on the sensing of biomarkers related to diabetes mellitus (DM) and diabetic retinopathy (DR) are presented, with the scope of helping and encouraging researchers to design sensor-array machine-learning (ML)-supported devices for robust, fast, and cost-effective early detection of these devastating diseases. First, we highlight the social relevance of developing systematic screening programs for such diseases and how sensor-arrays and ML approaches could ease their early diagnosis. Then, we present diverse works related to the colorimetric and electrochemical sensing of biomarkers related to DM and DR with non-invasive sampling (e.g., urine, saliva, breath, tears, and sweat samples), with a special mention to some already-existing sensor arrays and ML approaches. We finally highlight the great potential of the latter approaches for the fast and reliable early diagnosis of DM and DR.

Comprehensive Review on Wearable Sweat-Glucose Sensors for Continuous Glucose Monitoring.

The incidence of diabetes is increasing at an alarming rate, and regular glucose monitoring is critical in order to manage diabetes. Currently, glucose in the body is measured by an invasive method of blood sugar testing. Blood glucose (BG) monitoring devices measure the amount of sugar in a small sample of blood, usually drawn from pricking the fingertip, and placed on a disposable test strip. Therefore, there is a need for non-invasive continuous glucose monitoring, which is possible using a sweat sensor-based approach. As sweat sensors have garnered much interest in recent years, this study attempts to summarize recent developments in non-invasive continuous glucose monitoring using sweat sensors based on different approaches with an emphasis on the devices that can potentially be integrated into a wearable platform. Numerous research entities have been developing wearable sensors for continuous blood glucose monitoring, however, there are no commercially viable, non-invasive glucose monitors on the market at the moment. This review article provides the state-of-the-art in sweat glucose monitoring, particularly keeping in sight the prospect of its commercialization. The challenges relating to sweat collection, sweat sample degradation, person to person sweat amount variation, various detection methods, and their glucose detection sensitivity, and also the commercial viability are thoroughly covered.

Graphene Oxide Functionalized Biosensor for Detection of Stress-Related Biomarkers.

A graphene oxide (GO)-based cortisol biosensor was developed to accurately detect cortisol concentrations from sweat samples at point-of-care (POC) sites. A reference electrode, counter electrode, and working electrode make up the biosensor, and the working electrode was functionalized using multiple layers consisting of GO and antibodies, including Protein A, IgG, and anti-Cab. Sweat samples contact the anti-Cab antibodies to transport electrons to the electrode, resulting in an electrochemical current response. The sensor was tested at each additional functionalization layer and at cortisol concentrations between 0.1 and 150 ng/mL to determine how the current response differed. A potentiostat galvanostat device was used to measure and quantify the electrochemical response in the GO-based biosensor. In both tests, the electrochemical responses were reduced in magnitude with the addition of antibody layers and with increased cortisol concentrations. The proposed cortisol biosensor has increased accuracy with each additional functionalization layer, and the proposed device has the capability to accurately measure cortisol concentrations for diagnostic purposes.

Wearable soft electrochemical microfluidic device integrated with iontophoresis for sweat biosensing

A soft and flexible wearable sweat epidermal microfluidic device capable of simultaneously stimulating, collecting, and electrochemically analyzing sweat is demonstrated. The device represents the first system integrating an iontophoretic pilocarpine delivery system around the inlet channels of epidermal polydimethylsiloxane (PDMS) microfluidic device for sweat collection and analysis. The freshly generated sweat is naturally pumped into the fluidic inlet without the need of exercising. Soft skin-mounted systems, incorporating non-invasive, on-demand sweat sampling/analysis interfaces for tracking target biomarkers, are in urgent need. Existing skin conformal microfluidic-based sensors for continuous monitoring of target sweat biomarkers rely on assays during intense physical exercising. This work demonstrates the first example of combining sweat stimulation, through transdermal pilocarpine delivery, with sample collection through a microfluidic channel for real-time electrochemical monitoring of sweat glucose, in a fully integrated soft and flexible multiplexed device which eliminates the need of exercising. The on-body operational performance and layout of the device were optimized considering the fluid dynamics and evaluated for detecting sweat glucose in several volunteers. Furthermore, the microfluidic monitoring device was integrated with a real-time wireless data transmission system using a flexible electronic board PCB conformal with the body. The new microfluidic platform paves the way to real-time non-invasive monitoring of biomarkers in stimulated sweat samples for diverse healthcare and wellness applications.

Electrochemical determination of glucose in blood serum and sweat samples by the strontium doped Co3O4

• The conventional synthesis routes were investigated for the preparation of Sr doped Co 3 O 4 (Sr-Co 3 O 4 ). • The successful incorporation of Sr in Co 3 O 4 lattice was found for hydrothermal method. • The occupation of Sr in octahedral sites increases the non-stoichiometric oxygen in the Co 3 O 4 lattices. • These defected electronic structures were inspected against the electrocatalytic activity of glucose oxidation. • The Sr-Co 3 O 4 is applied in real-time monitoring of glucose in blood serum and sweat samples which received good recoveries. This work reports the noninvasive electrochemical determination of glucose by strontium doped cobaltic cobalt oxide nanostructures (Sr-Co 3 O 4 ). The Sr-Co 3 O 4 is prepared by three conventional methods namely hydrothermal, magnetic stirring, and ultrasound. Among all, the hydrothermal method effectively incorporated the Sr in the Co 3 O 4 lattice. The Sr percentage and Co oxidation states were investigated by x-ray photoelectron spectroscopy. The Sr has a more ionic radius than cobalt, therefore, it is occupied in the octahedral site. As a result, the non-stoichiometric oxygen content was increased in the Co 3 O 4 lattices, which are the main contributor to the electrochemical determination of glucose. The results revealed that hydrothermally synthesized Sr-Co 3 O 4 (HSC) exhibited improved electrocatalytic activity such as low peak potential (0.55 V) and high current (116 µA) towards glucose oxidation than the other electrocatalysts. The HSC/GCE revealed a good sensitivity (9.01 ± 0.15 µA mM −1 cm −2 ) and low LoD (31 ± 3 nM). Also, high selectivity was observed towards glucose detection in the presence of co-interfering species. Moreover, the Sr-Co 3 O 4 is applied in real-time monitoring of glucose in blood serum and sweat samples which received good recoveries.

Biofluids manipulation methods for liquid biopsy in minimally-invasive assays

The Liquid Biopsy (LB) is an opportunity for non-invasive diagnosis and prognosis of various diseases. To date, it isn't possible to consider that tissue biopsy can represent a pathology entirety. Then, body fluids are rich in a large number and variety of biomarkers and they can provide information about several diseases.•Recently, other biological fluids, easy to be collected are rising for their significant content of biomarkers and for the possibility to collect and manipulate them without the intervention of medical staff.•The management of biological fluids requires suitable storage methods. Temperature, storage time and physical stresses due to sample handling can lead to chemical and physical changes that may induce sample degradation and incorrect analysis.•The reliability of a diagnostic or screening test depends on its sensitivity and specificity. As the liquid biopsy is a 'snapshot' of a pathophysiological condition, it is crucial that its components do not degrade due to the improper handling of the body fluid.In this review, some handling methods of Saliva, Urine, Stool, Seminal Fluid, Tears and Sweat samples will be described, as well as protocols to facilitate the analysis of metabolites, nucleic acids, proteins and Extracellular Vesicles (EVs) from those unusual body fluids.