Stabilization of Salivary Biomarkers

Abstract

The use of saliva as a diagnostic biofluid has been increasing in recent years, thanks to the identification and validation of new biomarkers and improvements in test accuracy, sensitivity, and precision that enable the development of new noninvasive and cost-effective devices. However, the lack of standardized methods for sample collection, treatment, and storage contribute to the overall variability and lack of reproducibility across analytical evaluations. Furthermore, the instability of salivary biomarkers after sample collection hinders their translation into commercially available technologies for noninvasive monitoring of saliva in home settings. The present review aims to highlight the status of research on the challenges of collecting and using diagnostic salivary samples, emphasizing the methodologies used to preserve relevant proteins, hormones, genomic, and transcriptomic biomarkers during sample handling and analysis.

A Silk-Based Platform to Stabilize Phenylalanine Ammonia-lyase for Orally Administered Enzyme Replacement Therapy

“…We present here a silk fibroin based drug delivery system to address the stability limitations of PAL. Regenerated silk fibroin, a natural protein derived from the cocoons of Bombyx mori silkworms, is biocompatible and biodegradable and can be used to stabilize biomolecules, which makes it a good carrier for intrinsically labile molecules such as PAL. − In this study, we show that silk fibroin can preserve the bioactivity of PAL at room temperature when it is embedded in solid film formats. These films allowed for the stabilization of the enzyme for over a month without the need for refrigeration.…”

“…Stabilization of PAL in silk for prolonged storage without refrigeration was also evaluated. Silk fibroin is inherently stable to moisture and changes in temperature, thanks to its heterogeneous structure that generates protective microenvironments around labile molecules, including enzymes, drugs, and genomic content. ,,, PAL is currently on the market as a prefilled syringe that needs to be refrigerated at 2–8 °C. To perform an accelerated aging test, silk–PAL films were stored at 37 °C in an incubator and dissolved and analyzed after 7, 14, and 42 days.…”

Reshaping de Novo Protein Switches into Bioresponsive Materials for Biomarker, Toxin, and Viral Detection

“…Lyophilization within a stabilizing matrix (such as sugars or polyols) is a common method used to increase the thermal stability of labile molecules by reducing their molecular mobility and degradation processes. [ 30 ] Silk fibroin is an attractive matrix for lyophilization [ 39 ] to obtain stable lucKey‐lucCage/silk porous matrices that can be quickly (within seconds) dissolved for readout. Additionally, silk provides material versatility, including the ability to cast films which reduces the cost of fabrication and processing time and results in shelf‐stable formats that can be easily handled and shipped for analysis in the field.…”

Boronic Acid-Tethered Silk Fibroin for pH-Dependent Mucoadhesion

“…Importantly, the biodegradability of silk and the turnover of the mucus would make this a transient treatment, allowing natural healing processes to occur while providing temporary protection when the mucus layer is weakened. The versatility of silk would also enable the development of various formats that can be easily used by patients, including films, gels, ovules, and sprays. , As the mucus covers different inner epithelia, this work also provides various avenues for employing silk-BOH in the intestinal tract and the buccal mucosa.…”