It has surprisingly been discovered that it is possible to stabilize biomolecules such as RNA, DNA and proteins in biological samples such as cells, tissues, biopsies and blood using deep eutectic solvents (DES). It has also been discovered that DES mixtures can be used to fix and preserve cell morphology in biological samples such as tissue blocks, cancer biopsies and whole blood. This invention describes methods to stabilize and preserve biomolecules, whole cells, tissues, blood and biological samples using DES mixtures.

Disclosed herein are compositions for fixing tissue for cytologic, histomorphologic, and/or molecular analysis (e.g., DNA, RNA, and/or protein analysis). In some embodiments, the fixatives are aldehyde-free fixatives, for example, formaldehyde- or formalin-free fixatives. Particular disclosed compositions include buffered ethanol. The buffer is a phosphate buffer or phosphate buffered saline (PBS) in some examples. In further embodiments, the fixative includes additional components, such as glycerol and/or acetic acid.

It has surprisingly been discovered that it is possible to stabilize biomolecules such as RNA, DNA and proteins in biological samples such as cells, tissues, biopsies and blood using deep eutectic solvents (DES). It has also been discovered that DES mixtures can be used to fix and preserve cell morphology in biological samples such as tissue blocks, cancer biopsies and whole blood. This invention describes methods to stabilize and preserve biomolecules, whole cells, tissues, blood and biological samples using DES mixtures.

A single dissolving compound forms plural azeotropes, which can be azeotropically vaporized off at various stages of the treatment process, thus maintaining predictable concentrations of the chemicals present. The treatment process can be performed in the absence of formalin or related compounds which can interfere with the preservation of genetic material. A process for preserving a specimen includes using a dissolving compound that can form a plural number of azeotropes, at least one azeotrope being formed between one or more components of the dissolving compound and specimen-supplied water, and at least one azeotrope being formed between different components of the dissolving compound; successively and azeotropically vaporizing off formed azeotropes; and impregnating the specimen with a support medium.

Labeling and detection of clinoptilolite and other zeolites and aluminosilicates by means of lumogallion fluorescence reaction in paraformaldehyde-fixed animal and human cell cultures and tissue samples after administration of the mineral or in mineralogical-geological samples themselves.

A single dissolving compound forms plural azeotropes, which can be azeotropically vaporized off at various stages of the treatment process, thus maintaining predictable concentrations of the chemicals present. The treatment process can be performed in the absence of formalin or related compounds which can interfere with the preservation of genetic material. A process for preserving a specimen includes using a dissolving compound that can form a plural number of azeotropes, at least one azeotrope being formed between one or more components of the dissolving compound and specimen-supplied water, and at least one azeotrope being formed between different components of the dissolving compound; successively and azeotropically vaporizing off formed azeotropes; and impregnating the specimen with a support medium.

The present disclosure provides compositions and methods for using fixed biological samples in partition-based assays. In at least one embodiment, the disclosure provides a composition comprising a fixed biological sample and an un-fixing agent contained in a partition, such as a discrete droplet. In some embodiments, the disclosure provides un-fixing agent compounds capable of catalytically cleaving crosslinks in fixed biological samples, particularly crosslinked nucleic acids, such as RNA.

The present disclosure provides methods for carrying out Romanowsky-type stains, specifically Wright-Giemsa and May-Grnwald stains, quickly and efficiently. The methods greatly reduce the overall amount of time required to complete a Wright-Giemsa stain or a May-Grnwald stain of sufficient quality on a biological sample. The subject methods can be applied to both manual and automated staining procedures.

It has surprisingly been discovered that it is possible to stabilize biomolecules such as RNA, DNA and proteins in biological samples such as cells, tissues, biopsies and blood using deep eutectic solvents (DES). It has also been discovered that DES mixtures can be used to fix and preserve cell morphology in biological samples such as tissue blocks, cancer biopsies and whole blood. This invention describes methods to stabilize and preserve biomolecules, whole cells, tissues, blood and biological samples using DES mixtures.

A single dissolving compound forms plural azeotropes, which can be azeotropically vaporized off at various stages of the treatment process, thus maintaining predictable concentrations of the chemicals present. The treatment process can be performed in the absence of formalin or related compounds which can interfere with the preservation of genetic material. A process for preserving a specimen includes using a dissolving compound that can form a plural number of azeotropes, at least one azeotrope being formed between one or more components of the dissolving compound and specimen-supplied water, and at least one azeotrope being formed between different components of the dissolving compound; successively and azeotropically vaporizing off formed azeotropes; and impregnating the specimen with a support medium.