ioacts provides the full spectral range of reactive fluorescent dyes such as FSD Fluor™, FSD, Flamma® Fluors, ICG and other traditional dyes equipped with variety of reactive and functional groups along with fluorescent quenchers.

Fluorescence labeled proteins and antibodies might provide great advantages in the identification of their binding partners or in the observation of biological processes. They allow to visualize cellular environment, to define their function, regulation and interactions. In advanced assays, fluorescent proteins can be utilized in measuring of protein–protein interactions or conformational changes, by measuring intensity changes or FRET energy transfer. An ideal fluorescent label should be small, bright, stable, and without any perturbation to the biological system. Additionally, the fluorescence labeling should be performed at non-active site with the possibility for multiplexing and avoided to the tendency to aggregate.

Organic fluorescent dye-labeled proteins have superior properties over fluorescent protein–conjugated counterparts including, wide spectral range, smaller size, greater photostability, and higher brightness. However, dye–labeled proteins also have some limitations that their sensitivity is low due to lack of the amplification step associated with the secondary antibody, and the protein should be free of contaminants and stabilizing agents. BioActs provides a wide range of fluorophore-conjugated proteins and antibodies for a variety of biological applications.

The live cell imaging with fluorescent probes can give opportunities to analyze cellular events in real–time thereby lead to new biological discoveries those unachievable with traditional analysis methods. Conventional techniques, such as flow cytometry and antibody immunocytochemistry staining, analyze cellular events as a snapshot rather than in real–time. We offer novel fluorescent cell imaging probes for cell structure analysis, apoptosis and angiogenesis imaging, ROS detection, etc.

In vivo optical imaging techniques might provide opportunities to observe the dynamic real–time localization and translocation of molecules in living cells. In vivo fluorescence imagings are being applied in preclinical research studies, and real–time in vivo studies using animals have been used to track cell–based therapies and to monitor the response to chemotherapies. Other fields of in vivo imaging applications are elucidation of fundamental processes in living organisms or assessment of stem cell differentiation, etc. BioActs provides a range of reagents and probes such as near–infrared (NIR) fluorescent dyes and conjugated probes for in vivo study. The unparalleled photochemical properties of our probes might offer new opportunity in animal and in vivo imaging applications.

In vitro diagnostics analyze samples that taken from the human body such as blood or tissue. In vitro diagnostics enable to detect specific disease or other conditions and to simultaneously provide multiple test results. In vitro diagnostics can be used to find specific medicine or therapy for patients whom to benefit from the treatment. In vitro diagnostics may also be used to monitor a person’s overall health to help cure, treat, or prevent diseases. BioActs provides a variety of in vitro diagnostic (IVD) materials such as fluorescent polystyrene beads, magnetic nanoparticles, dyes, MRSA and MRAB detection kit, PCR kit, immuno staining kit, organ clearing kit, etc.

The optimal labeling condition for biomolecules is to achieve an appropriate degree of conjugation ratio yet to retain the important functionality of the original biomolecules such as binding affinity, activatory or inhibitory activity, solubility and biological membrane permeability. The high-number of labeling often causes conjugated biomolecule to precipitate out of solution or to lose its functional properties, thus the degree of labeling should be determined from experimental optimization process. There are two major types of reactive dyes: amine-reactive dye and thiol-reactive dye. The primary target of amine-reactive probes at protein is lysine residue, and thiol residue is the main target for thiol-reactive probes. In mammalian proteins, the occurrence frequency of lysine residue is 7.2% and that of thiol is 3.3%.

Amino-labeling is the widely utilized method to conjugate proteins, peptides, oligonucleotides and other biomolecules with dyes. Amine-reactive dyes might be used to prepare bioconjugates for fluorescent analog cytochemistry, immunochemistry, cell tracing, receptor labeling, FITC, etc. The primary target for amine-reactive probe is lysine residue, which has the fifth highest occurrence frequency of the 20 natural amino acids in mammalian proteins. A typical IgG antibody has about 90 lysine residues, and the maximum number of labeling will be around 30 residues with excess amount of reagent and prolonged incubation. However, maintaining functional properties requires the degree of labeling less than 10 dyes per antibody. BioActs provides three major classes (NHS, Sulfo-MHS and Vinylsulfone) of amine-reactive Flamma® Fluors dyes, and they can cover the entire spectral range from visible to NIR region.

Thiol-reactive dyes are mainly used for labeling proteins for the observation of conformational change, multi-subunit complexes assembly and ligand-binding processes. In proteins and peptides, the primary targets of thiol-reactive probes are cysteine residues. Unlike amine-labeling, the low abundance of cysteine residues enable to achieve saturated labeling without risk of conjugated protein precipitation and fluorescence self-quenching interactions. Thiols play a principal role in maintaining the appropriate oxidation–reduction state of proteins, cells and organisms, and they are easily oxidized to form disulfides. Thiols can also be generated by the reduction of cysteine disulfides with reducing agents such as dithiothreitol (DTT), 2-mercaptoethanol or tris-(2-carboxyethyl)phosphine (TCEP). However, the reducing process may cause to disrupt the tertiary structure of protein. Maleimide is a well-known reactive group that can specially label thiol of cysteine residue without interacting with amino functionality. In labeling process, thiol is added to the double bond of maleimide via 1,4-addition pathway to form thioether linkage. Maleimides apparently do not react with methionine, histidine or tyrosine, but they also react with amines in the strong basic environment. BioActs offers Flamma® Fluors maleimide series as thiol-reactive fluorescence dyes.

Click chemistry is a typical type of bioorthogonal reactions, which the reaction occurs inside of living systems yet without interfering with native biochemical processes. The most widely utilized click chemistry is 1,3-dipolar cycloaddition between an azide and an alkyne to produce 1,4-disubstituted 1,2,3-triazole. The triazole ring is stable under hydrolysis, oxidation or reduction, and it survives ionization process in mass spectrometry (MS) analysis. There are two types of 1,3-dipolar cycloaddition methods: copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) and strain-promoted azide-alkyne cycloaddition (SPAAC). BioActs offers Flamma® Fluors Alkyne dyes for CuAAC, Flamma® Fluors ADIBO products for SPAAC and Flamma® Fluors Azide dyes for both CuAAC and SPAAC.