Individual Capsules Research Articles

Long-term tracing of individual human neural cells using multiphoton microscopy and photoconvertible polymer capsules.

The study of human neural cells, their behaviour and migration are important areas of research in the biomedical field, particularly for potential therapeutic applications. The safety of using neural cells in therapy is still a concern due to a lack of information on long-term changes that may occur. While current methods of cell tracing explore gene manipulations, we elaborate approaches to cell marking with no genetic interference. In this study, we present a novel method for labelling and tracking neural cells using cell-impregnatable photoconvertible polyelectrolyte microcapsules. These capsules demonstrated low cytotoxicity with no effect on the differentiation ability of the neural cells, maintained a high level of fluorescent signal and ability for tracing individual neural cells for over 7 days. The capsules modified with rhodamine- and fluorescein-based dyes were demonstrated to undergo photoconversion by both one- and two-photon lasers while being internalized by neural cells. The finding gives the possibility to select individual capsules inside multicellular structures like spheroids and tissues and alternate their fluorescent appearance. Thus, we can track individual cell paths in complex systems. This new method offers a promising alternative for studying neural cells' long-term behaviour and migration in complex systems such as three-dimensional cellular populations.

CO2-TBAB semi-clathrate hydrate dissociation behaviour in individual capsules: A new two-stage numerical model and parametric study

Gas hydrates have a wide implementation in the capture, storage, transport and utilisation of a range of gases, in which the dissociation kinetics is of great importance to gas transport and recovery efficiency. Encapsulation has been proven an effective technique to enhance gas–liquid mass transfer and thus improve gas hydrate formation kinetics. However, the dissociation behaviour of gas hydrate in individual capsules remains unknown. In this work, the dissociation kinetics of encapsulated CO2-TBAB semi-clathrate hydrates in different shapes are experimentally investigated under various operating conditions, and, for the first time, a two-stage numerical model is developed which integrates mass transfer, heat transfer and the intrinsic gas hydrate reaction kinetics to simulate the gas hydrate dissociation process. The effects of temperature, pressure, capsule volume and capsule geometry on gas hydrate dissociation kinetics are investigated. The results reveal that the proposed model is capable of capturing two distinct experimentally-observed dissociation stages, a rapid and subsequently slow stage according to the measured dissociation rate. Surface-to-volume ratio of the capsule and the dissociation driving force are the two main factors influencing the dissociation kinetics. The ring-shaped capsule exhibits the most efficient dissociation process due to its high surface-to-volume ratio and long transition time to the slow dissociation stage. This work enhances the understanding of gas hydrate dissociation behaviour in individual capsules and guides the manipulation of dissociation for efficient hydrate-based gas transport and recovery.

Bacterial Diversity in Egg Capsular Fluid of the Spotted Salamander Ambystoma maculatum Decreases with Embryonic Development.

Egg capsules within egg masses of the spotted salamander Ambystoma maculatum host a symbiosis with the unicellular green alga Oophila amblystomatis. However, this alga is not the only microbe to inhabit those capsules, and the significance of these additional taxa for the symbiosis is unknown. Spatial and temporal patterns of bacterial diversity in egg capsules of A. maculatum have recently begun to be characterized, but patterns of bacterial diversity as a function of embryonic development are unknown. We sampled fluid from individual capsules in egg masses over a large range of host embryonic development in 2019 and 2020. We used 16S rRNA gene amplicon sequencing to examine how diversity and relative abundance of bacteria changed with embryonic development. In general, bacterial diversity decreased as embryos developed; significant differences were observed (depending on the metric) by embryonic development, pond, and year, and there were interaction effects. The function of bacteria in what is thought of as a bipartite symbiosis calls for further research.

Assessment of MDMA tablet and capsule dosages from seizures in Queensland, Australia

3,4-Methylenedioxymethamphetamine (MDMA) is prominent in the illicit drug market and usually presents as tablets, capsules, or crystal. Drug purity determinations are typically performed in the Forensic Chemistry, Queensland Health Forensic and Scientific Services (QHFSS) laboratory on homogenised samples, yielding an average MDMA concentration which can be used to calculate average MDMA dosages (mg) per unit (i.e., tablet or capsule). Little published research exists however regarding individual dosage variability and drug content of capsules and tablets in the Australian illicit drug market. This study assessed selected tablet and capsule submissions as a part of routine casework over an 18-month period primarily to examine MDMA dosage variations between tablets or capsules within the same exhibit. Additionally, dosage variations from different seizures of the same logo or appearance were investigated where possible. Generally, tablet exhibits were found to have consistent dosages however, there were several instances where large variations were noted. These dosage variations were often attributable to inconsistent tablet whole weights, compounded by differences in MDMA concentration within tablets. MDMA dosage differences in capsule presentations were generally due to differences in capsule contents weight with some instances of individual capsules recording double the MDMA dosage of other capsules in the same seizure. To complement this study, results from all available MDMA detections from 2017 to 2020 in the QHFSS laboratory were examined. Average MDMA concentrations within tablets, capsules and crystal presentations increased during that time. Correspondingly, average MDMA dosages increased within capsule and tablet presentations, noting there was still a substantial range of MDMA dosages observed within capsule and tablet presentations. Finally, the presence of adulterants (psychoactive or non-psychoactive) in combination with MDMA was reported in a small proportion of cases, and more frequently in tablets than capsules. This study has provided a comprehensive survey and highlights the potential dosage variability that may be encountered in MDMA presentations in Queensland.

In Vitro Stability and Recovery Studies of Pimavanserin in Water and in Different Vehicles Orally Administered.

Background and objectiveSwallowing difficulties (i.e., dysphagia) occur in up to 40% of the adult general population, particularly among the elderly prescribed solid oral dosage forms. Pimavanserin is approved for the treatment of hallucinations and delusions in patients with Parkinson’s disease psychosis (PDP) as a 34-mg capsule formulation. Patients with PDP may be at-risk for dysphagia that could affect administration of intact pimavanserin capsules. The stability of oral pimavanserin was evaluated in different liquid/soft food vehicles.MethodsThe stability of pimavanserin intended for oral administration was assessed by sprinkling the contents of 1 pimavanserin 34-mg capsule into water (40 mL), applesauce (40 g), vanilla Ensure (60 mL), or non-pulp orange juice (60 mL).ResultsThe stability study demonstrated >95% recovery within 24 hours after contents of a 34-mg pimavanserin capsule were dispersed in applesauce, vanilla Ensure®, orange juice, or water. Assay values at 24 h for individual capsules were within 5% of time zero, and no significant change in the impurity profile was observed in any vehicle. Pimavanserin degradation products recovered from various food vehicles for individual and total degradation products were < 0.5% at all time points. In addition, the impurity profile of compatibility samples matched that obtained for a control sample. ConclusionThese results support the ability of pimavanserin to be given orally by emptying the capsule contents into soft foods or liquids in accordance with the product label.

Relation between amino-truncated amyloid beta peptide (AßN3-42 and AßN11-42) mitochondrial deposition and the activation of inflammation-oxidative mechanisms in the lens epithelium in age-related cataract from diabetic patients.

AD is characterized by the formation of senile plaques and neurofibrillary tangles. Senile plaques are deposits of amyloid beta-peptide 1-42 (Aβ42) and another species of amyloid peptides known as amino-truncated (N-truncated) species; AßN3-42 and AßN11-42. These peptides cause neuronal and synapse loss. Age-related cataract (ARC), the opacification of the crystalline lens, is one of the leading causes of blindness in the world. It has been reported the presence of amyloid peptides in teens capsule form ARC patients. However, the intracellular localization and rol of these peptides in the anterior capsule (lens epithelial cells) have not been described yet as well as the possible mechanisms involved. The aim of this study was to determine the correlation between the presence of N-truncated species in the anterior lens capsule of diabetic (DP) and nondiabetic patients (NDP) with age-related cataract (ARC) and pro-inflammatory and oxidant markers. Informed consent was obtained from all patients. Samples were collected from 30 age-related cataract from DP over 50 years of age with LOCS II score of nuclear color ≥4 along with 30 ARC from NDP' subjects after phacoemulsification surgery. Lens capsules, were processed for IMH, IF, WB and dot blot . Monoclonal anti-Aß-1-42, anti-AßN3-42 and anti AßN11-42, were used. anti-VDAC, anti-TSPO, anti-TOM-20, were used in double immunofluorescence assays to detect amyloid peptides in mitochondria. anti-IL-6, anti-TNF-a, anti-IL-17, anti- IL-10, anti-INF-γ were used as inflammation markers and anti-SOD, anti-catalase and anti-glutathione were used to detect oxidative changes in ARC. For WB and dot blot assay individual capsules were collected from each group were used. The results show the presence of Aβ42, AßN3-42 and AßN11-42 peptides in the mitochondria from cells of the anterior lens capsule from DP. There are statistically differences in the accumulation of AßN3-42 in mitochondria from ARC from DP. Inflammatory as well as oxidative markers show the activation of both pathological pathways and a positive correlation between them. There is a correlation between amyloid peptides accumulation and the activation of pathological pathways on lens capsules in diabetic patients and these N-truncated peptides detection in the eye could be useful as AD early diagnostic.

An overview of composite pressure vessels with polymer liner

Pressure vessels are one of the most widely used equipment in various industries. Pressure vessels are divided into four types based on material and structure. Weakness in design, construction and production, service and incorrect choice of materials are the causes of failure of pressure vessels. With the introduction of composites into the world of pressure vessels, many design weaknesses and mechanical properties of the pressure vessel are improved. By using high density polymers, the weight of the pressure vessel is reduced. Type IV pressure vessels with the simultaneous use of composite structure and polymer liner has been able to increase its weight and useful life to one-fifth and twice the type I pressure vessels, respectively. Corrosion resistance, no fatigue in consecutive loads, lightness and portability, high operating pressure (700 bar) and lack of complexity in the production method are the advantages and high production costs due to the use of carbon fibers are the disadvantages of the fourth type pressure vessels. These pressure vessels are used to storing alternative fuels such as hydrogen and portable individual oxygen capsules. In this brief study, the fourth type of pressure vessels with other types have been studied and compared.

Patterns of bacterial diversity in embryonic capsules of the spotted salamanderAmbystoma maculatum: an expanding view of a symbiosis

The unicellular green alga, Oophila amblystomatis, populates egg capsules of the spotted salamander Ambystoma maculatum. This nutrient-exchange mutualism is widely perceived as a bipartite interaction, but the presence and contributing effects of bacteria to this symbiosis are unknown. We used standard cultivation techniques and amplicon sequencing of the V4/V5 region of 16S rRNA gene to identify and compare diversity of bacterial taxa in embryonic capsules with that in the aquatic breeding habitat. Our sampling regime allowed us to investigate diversity among individual capsules of an egg mass and between two ponds and sampling years. Capsules contain much lower diversity of bacteria than pond water, and spatial and temporal variation in intracapsular and pond bacterial diversity was observed. Despite this variation, sequences corresponding to species in the orders Burkholderiales and Oligoflexales were either prevalent or abundant, or both. Isolates most commonly recovered from capsules were closely related to species in the genus Herbaspirillum (Burkholderiaceae); other isolates were pseudomonads, but in all cases are closely related to known vascular plant-associated species. We conclude that, despite observed variation, there are bacterial taxa whose presence is held in common spatially and temporally among capsules and that the symbiosis between O. amblystomatis and A. maculatum may involve these taxa.

Pharmacopoeia: Illness narratives.

Pharmacopoeia: Illness narratives.

Ca2+ Signaling: Stimulation of Local Cytosolic Calcium Release by Photothermal Heating for Studying Intra‐ and Intercellular Calcium Waves (Adv. Mater. 24/2021)

Near-infrared light excitation of individual polymeric capsules with integrated plasmonic nanoparticles enables release of Ca2+. The small amount of released Ca2+ from lysosomes rapidly triggers robust Ca2+ release from the endoplasmic reticulum, leading to a propagating intra- and intercellular calcium waves, as described by Wolfgang J. Parak and co-workers in article number 2008261.

Improved Sentinel Method for Surveillance and Collection of Filth Fly Parasitoids.

Parasitoids are important natural enemies of house flies and other muscoid flies. The two most commonly used methods for collecting fly parasitoids from the field have distinct advantages and disadvantages. Collections of wild puparia depend on the ability to find puparia in sufficient numbers and are prone to localized distortions in relative species abundance because of the overrepresentation of samples from hot spots of fly larval activity. Placement and retrieval of sentinel puparia is convenient and allows consistent sampling over time but is strongly biased in favor of Muscidifurax spp. over Spalangia spp. An improved sentinel method is described that combines some of the advantages of these two methods. Fly medium containing larvae is placed in containers, topped with a screen mesh bag of puparia, and placed in vertebrate-proof wire cages. Cages are placed at sites of actual or potential fly breeding and retrieved 3-7 d later. The modified method collected species profiles that more closely resembled those of collections of wild puparia than those from sentinel pupal bags. A method is also described for isolating puparia individually in 96-well tissue culture plates for parasitoid emergence. Use of the plate method provided a substantial saving of time and labor over the use of individual gelatin capsules for pupal isolation. Puparia from the collections that were housed individually in the wells of tissue culture plates had a higher proportion of emerged Spalangia species than puparia that were held in groups.

A Capsule-Based Model for Immature Hard Tick Stages Infestation on Laboratory Mice.

Ticks are obligatory blood feeding parasites at all stages of development (except eggs) and are recognized as vectors of various pathogens. The use of mouse models in tick research is critical for understanding their biology and tick-host-pathogen interactions. Here we demonstrate a non-laborious technique for the feeding of immature stages of hard ticks on laboratory mice. The benefit of the method is its simplicity, short duration, and the ability to monitor or collect ticks at different time points of an experiment. In addition, the technique allows attachment of two individual capsules on the same mouse, which is beneficial for a variety of experiments where two different groups of ticks are required to feed on the same animal. The non-irritating and flexible capsule is made from easily accessible materials and minimizes the discomfort of the experimental animals. Furthermore, euthanasia is not necessary, mice recover completely after the experiment and are available for re-use.

Deformation and sorting of capsules in a T-junction

We study experimentally the motion and deformation of individual capsules transported by a constant volume-flux flow of low Reynolds number, through the T-junction of a channel with rectangular cross-section. We use millimetric ovalbumin-alginate capsules which we manufacture and characterise independently of the flow experiment. Centred capsules travel at constant velocity down the straight channel leading to the T-junction where they decelerate and expand in the spanwise direction before turning into one of the two identical daughter channels. There, non-inertial lift forces act to re-centre them and relax their shape until they reach a steady state of propagation. We find that the dynamics of fixed-size capsules within our channel geometry are governed by a capillary number Ca defined as the ratio of viscous shear forces to elastic restoring forces. We quantify the elastic forces by statically compressing the capsule to 50% of its initial diameter between parallel plates rather than by the Young's modulus of the encapsulating membrane, in order to account for different membrane thickness, pre-inflation and non-linear elastic deformation. We show that the maximum extension in the T-junction of capsules of different stiffness collapses onto a master curve in Ca. Thus, it provides a sensitive measure of the relative stiffness of capsules at constant flow rate, particularly for softer capsules. We also find that the T-junction can sort fixed-size capsules according to their stiffness because the position in the T-junction from which capsules are entrained into the daughter channel depends uniquely on Ca. We demonstrate that a T-junction can be used as a sorting device by enhancing this initial capsule separation through a diffuser.

Characterization of Core-Shell Alginate Capsules

A new droplets millifluidic/inverse gelation based process was used to produce core-shell alginate milli-capsules. Water-in-oil (W/O) emulsion dispersed phase containing Ca2+ ions was directly injected into a continuous alginate phase to generate a secondary W/O/W emulsion. Due to the cross-linking of alginate molecules by Ca2+ ions release, core-shell milli-capsules were formed with a very high oil loading. The influence of the curing time and of the storage conditions on capsules physico-chemical properties were investigated. It was first found as expected that alginate membrane thickness increased with curing time in the collecting bath. However, a plateau was reached for the higher curing times, in close relation with previous observations (Martins, Poncelet, Marquis, Davy, & Renard, 2017b) that an external oil layer surrounded the surface of W/O emulsion drops that acted as a barrier and hindered the release of aqueous CaCl2 droplets during curing time. Compression experiments on individual capsules revealed that alginate membrane thickness was inversely related to its mechanical properties, i.e. the thicker membrane, the lower surface Young modulus. Surface Young modulus ranged from 61 to 26 N/m at curing times of 3 and 45 min, respectively. This result was explained in terms of enhanced swelling properties of alginate membrane with curing time or storage conditions. Drying capsules led to much more resistant membranes due to the loss of water. Oil loading of 80 wt% was obtained for dry capsules whatever the conditions used.

In Vitro Dissolution Evidence for Delivering Multiple Vitamin-Mineral Ingredients past the Stomach by Novel Capsule Delivery System (P24-009-19)

ObjectivesThe ability of a novel beadlet-in-oil, gastric-resistant, vegetarian capsule containing a multiple vitamin-mineral (MVM) composition to deliver capsule contents past the stomach was tested by standard in vitro tablet disintegration procedures using magnesium as the marker of capsule contents dissolution. MethodsA novel capsule design using a gastric-resistant vegetarian hypromellose/gellan gum capsule (DRcaps®, Capsugel®) was tested for disintegration in a standard tablet disintegration apparatus according to compendial United States Pharmacopeia methods, as per Good Manufacturing Practices for dietary supplements. The MVM ingredients were encapsulated into size 0 Vcaps® (hypromellose with no gastric acid resistance) and DRcaps®. Individual capsules were placed into chambers containing simulated gastric fluid (0.1 M HCl) for 120 minutes then changed to simulated intestinal fluid (buffered 2% sodium lauryl sulfate, pH 6.0) for an additional 300 minutes. Aliquots were tested for magnesium concentration at ten time points by atomic absorption spectrometry. ResultsMagnesium was contained inside coated beadlets along with ferrous bisglycinate, methylcobalamin, 5-methyltetrahydrofolate, calcium fructoborate and cellulose. Vcaps® released 50% of the magnesium between 30–45 minutes and all by 60 minutes in the acid phase. DRcaps® released 25% of the magnesium at 45 minutes, and 43% at 120 minutes, followed by slow, steady release of the remaining magnesium by 420 minutes. ConclusionsThese dissolution profiles reproduce the known, rapid disintegration profile of Vcaps® when wetted. DRcaps® released the majority of their contents after the pH was changed to intestinal conditions, and then the beadlets released the water-soluble ingredients (magnesium) in a linear manner over a two hour period. Since normal stomach emptying of DRcaps® without a meal is less than 20–30 minutes (previously shown), DRcap® MVMs bypass the stomach almost completely to release ingredients in the small intestine. Thus, a novel, beadlet-in-oil, gastric-resistant capsule delivered its contents past the stomach. These properties have the ability to improve tolerability and thus, compliance with users. Funding SourcesCapsugel®, Greenwood, SC, conducted this study for Ritual. Supporting Tables, Images and/or Graphs▪

Optimization of shear thickening fluid encapsulation technique and dynamic response of encapsulated capsules and polymeric composite

In this work, shear thickening fluid (STF) was fabricated and encapsulated by using three different encapsulation methods for the first time. The mechanical properties of individual STF capsules were investigated to obtain optimal encapsulation method and formula. Much more energy can be absorbed for STF capsules during impact than that of quasi-static compression. The introduction of ultraviolet (UV) curable resin can significantly improve the static strength of STF capsule and thus enhance the handleability of STF capsule. The STF capsules synthesized through the two-step polymerization method show an elastic shell which can stand multiple impacts without any damage. This STF capsule possesses higher static strength and absorbs more strain energy than capsules synthesized through the other two methods. Furthermore, incorporation of the STF capsules into silicone gel enhances the energy absorption capacity of matrix material up to 71.3%.

Functional Capsules via Subcomponent Self-Assembly.

Coordination-driven self-assembly can produce large, symmetrical, hollow cages that are synthetically easy to access. The functions provided by these aesthetically attractive structures provide a driving force for their development, enabling practical applications. For instance, cages have provided new methods of molecular recognition, chirality sensing, separations, stabilization of reactive species, and catalysis. We have fruitfully employed subcomponent self-assembly to prepare metal-organic capsules from simple building blocks via the simultaneous formation of dynamic coordinative (N→metal) and covalent (N═C) bonds. Design strategies employ multidentate pyridyl-imine ligands to define either the edges or the faces of polyhedral structures. Octahedral metal ions, such as FeII, CoII, NiII, ZnII, and CdII, constitute the vertices. The generality of this technique has enabled the preparation of capsules with diverse three-dimensional structures. This Account highlights how fundamental investigations into the host-guest chemistry of capsules prepared through subcomponent self-assembly have led to the design of useful functions and new applications. We start by discussing simple host-guest systems involving a single capsule and continue to systems that include multiple capsules and guests, whose interactions give rise to complex functional behavior. Many of the capsules presented herein bind varied neutral guests, including aromatic or aliphatic molecules, biomolecules, and fullerenes. Binding selectivity is influenced by solvent effects, weak non-covalent interactions between hosts and guests, and the size, shape, flexibility, and degree of surface enclosure of the inner spaces of the capsules. Some hosts are able to adaptively rearrange structurally or express a different ratio of cage diastereomers to optimize the guest binding ability of the system. In other cases the bound guest can be either protected from degradation or catalytically transformed through encapsulation. Other capsules bind anions, most often in organic solvents and occasionally in water. Complexation is usually driven by a combination of electrostatic interactions, hydrogen bonding, and coordination to additional metal centers. Anion binding can also induce cage diastereomeric reconfiguration in a similar manner to some neutral guests, illustrating the general ability of subcomponent self-assembled capsules to respond to stimuli due to their dynamic nature. Capsules have been developed as supramolecular extractants for the selective removal of anions from water and as channels for transporting anions through planar lipid bilayers and into vesicles. Different capsules may work together, allowing for functions more complex than those achievable within single host-guest systems. Incorporation of stimuli-responsive capsules into multicage systems allows individual capsules within the network to be addressed and may allow signals to be passed between network members. We first present strategies to achieve selective guest binding and controlled guest release using mixtures of capsules with varied affinities for guests and different stabilities toward external stimuli. We then discuss strategies to separate capsules with encapsulated cargos via selective phase transfer, where the solvent affinities of capsules change as a result of anion exchange or post-assembly modification. The knowledge gained from these multicage systems may lead to the design of synthetic systems that can perform complex tasks in biomimetic fashion, paving the way for new supramolecular technologies to address practical problems.

Investigation of albumin-derived perfluorocarbon-based capsules by holographic optical trapping

Albumin-derived perfluorocarbon-based capsules are promising as artificial oxygen carriers with high solubility. However, these capsules have to be studied further to allow initial human clinical tests. The aim of this paper is to provide and characterize a holographic optical tweezer to enable contactless trapping and moving of individual capsules in an environment that mimics physiological (in vivo) conditions most effectively in order to learn more about the artificial oxygen carrier behavior in blood plasma without recourse to animal experiments. Therefore, the motion behavior of capsules in a ring shaped or vortex beam is analyzed and optimized on account of determination of the optical forces in radial and axial direction. In addition, due to the customization and generation of dynamic phase holograms, the optical tweezer is used for first investigations on the aggregation behavior of the capsules and a statistical evaluation of the bonding in dependency of different capsule sizes is performed. The results show that the optical tweezer is sufficient for studying individual perfluorocarbon-based capsules and provide information about the interaction of these capsules for future use as artificial oxygen carriers.

Hatching plasticity in the tropical gastropod Nerita scabricosta

AbstractHatching plasticity has been documented in diverse terrestrial and freshwater taxa, but in few marine invertebrates. Anecdotal observations over the last 80 years have suggested that intertidal neritid snails may produce encapsulated embryos able to significantly delay hatching. The cause for delays and the cues that trigger hatching are unknown, but temperature, salinity, and wave action have been suggested to play a role. We followed individual egg capsules of Nerita scabricosta in 16 tide pools to document the variation in natural time to hatching and to determine if large delays in hatching occur in the field. Hatching occurred after about 30 d and varied significantly among tide pools in the field. Average time to hatching in each pool was not correlated with presence of potential predators, temperature, salinity, or pool size. We also compared hatching time between egg capsules in the field to those kept in the laboratory at a constant temperature in motionless water, and to those kept in the laboratory with sudden daily water motion and temperature changes. There was no significant difference in the hatching rate between the two laboratory treatments, but capsules took, on average, twice as long to hatch in the laboratory as in the field. Observations of developing embryos showed that embryos in the field develop slowly and continuously until hatching, but embryos in the laboratory reach the hatching stage during the first month of development and remain in stasis after that. Instances of hatching plasticity in benthic marine invertebrates, like the one in N. scabricosta, could greatly enhance our ability to investigate the costs and benefits of benthic versus planktonic development, a long‐standing area of interest for invertebrate larval biologists.

Temperature dependent mechanical properties of air, oil and water filled microcapsules studied by atomic force microscopy

We measured the mechanical properties of air and oil(tetradecane)filled cross-linked lysozyme as well as water filled metal phenolate microcapsules using atomic force microscopy in the temperature range of 21–70 °C. The stiffness and modulus of the individual capsules were determined using Reissner's theory for indentation of thin elastic shells. We found that the stiffness and modulus of air filled cross-linked lysozyme capsules decreases by a factor of 4 when the temperature changes from room temperature to human body temperature of 37 °C. However, the stiffness of tetradecane filled cross-linked lysozyme microcapsules decreases by 16% for the same change in the temperature. The stiffness decreases drastically for both air and tetradecane filled cross-linked lysozyme capsules when the temperature is increased to 70 °C. The air filled capsules shrink when heated to 70 °C for an hour due to leakage of air into the surrounding liquid medium. The heat treated air filled capsules were burst or broken with application of small forces. In contrast, the oil filled cross-linked lysozyme capsule retained their structure at 70 °C even though they became soft. The post heat treated tetradecane filled capsule had lower stiffness than its initial stiffness after cooling back to room temperature. The water filled metal phenolate capsules showed a minor dependence on temperature where they became slightly stiffer with increase in temperature. The reduction in the modulus of air filled capsules may have implications in their use as ultrasound contrast agents. The thermal response of tetradecane filled cross-linked lysozyme capsules has significant implication in their use as flavour or nutrient delivery vehicles in the processed food industry.