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Nanocelluloses (NCs), with their remarkable characteristics, have proven to be one of the most promising “green” materials of our times and have received special attention from researchers in nanomaterials. A diversity of new functional materials with a wide range of biomedical applications has been designed based on the most desirable properties of NCs, such as biocompatibility, biodegradability, and their special physicochemical properties.
NCs Type |
Drug Delivery System |
Drug |
Drug-Release Conditions |
Drug Release Mechanism |
Ref. |
---|---|---|---|---|---|
CNC |
cCNC/SA double-membrane hydrogels |
CH, EGF |
PBS, pH 7.4, 37 °C; t90% = 3 days (CH); t90% = 4 to 8 days (EGF). |
Swelling/erosion |
[89] |
TEMPO-oxidized CNC/CSos |
PrHy, IMI |
PBS, pH 7.4, room temp.; t40% = 12 min (PrHy); t80% = 2 h (IMI). |
- |
[90] |
|
CNC-HDQ complex |
HDQ |
dH2O, room temp., in the dark; t40% = 1 h; t80% = 4 h. |
- |
[91] |
|
CS/CNC nanocomposite hydrogels |
C |
SGF, pH 1.2, 37 °C; 120 min: 65% (0.5% CS/CNC); 50% (2.5% CS/CNC). |
Ritger–Peppas model; n = 0.61–0.66; Non-Fickian diffusion. |
[92] |
|
QC/cCNC/β-GP nanocomposite hydrogels |
DOX |
PBS, pH 7.4, 37 °C; t90% = 4 days (0% cCNC); t90% = 7 days (1% cCNC); t90% = 17 days (2.5% cCNC). |
Swelling/erosion |
[93] |
|
Gel/CNC nanocomposite hydrogels |
TPh |
SGF, pH 1.2, 37 °C; 24 h: 90% (5% CNC); 85% (10% CNC); 60% (25% CNC). |
- |
[94] |
|
m-CNC/Alg hydrogels |
Ibu |
PBS, pH 7.4, 37 °C; t = 0–30 min; 45%–60% burst release; t = 30–330 min; sustained release. |
Fickian diffusion |
[95] |
|
CNF |
PDA/TEMPO-CNF composite hydrogels |
TCH |
PBS; “On-off” drug release under NIR irradiation; 120 min: 60% (pH 5.0); 30% (pH 7.4); 15 h: 70% (pH 5.0); 55% (pH 7.4). |
Korsmeyer–Peppas model; Non-Fickian diffusion. |
[96] |
CNF/HPMC nanocomposites |
KT |
PBS, pH 7.4; 8 h: 95% (5% CNF), 62% (0.5% CNF), 56% (0.75% CNF), 37% (1% CNF). |
Non-Fickian diffusion; n = 0.52–0.61. |
[97] |
|
CNF/Alg hydrogels |
MH |
SGF, pH 1.2; SIF, pH 7.4, 37 °C; T40% = 90 min (CNF/Alg-50/50, SGF) t80% = 145 min (CNF/Alg-50/50, SIF). |
Fickian diffusion mechanism |
[98] |
|
BNC |
BNC-SA hybrid hydrogels |
Ibu |
PBS, pH 1.5, 7.0 and 11.8; 37 °C; 24 h: 90% (pH 11.8); 80% (pH 7.0); and 60% (pH 1.5); PBS, pH 7.4; 0.15 V, 0.3 V, 0.5 V; 24 h: 95% (0.5 V); 85% (0.3 V and 0.15 V); 80% (0 V). |
Korsmeyer–Peppas model; Non-Fickian diffusion; pH; n = 0.498–0.772; E-field; n = 0.700–0.491. |
[99] |
TCH-loaded BNC composites |
TCH |
HEPES buffers, pH 7, 37 °C; 3 h: ~100% (free TCH); 90% (0.5% TCH); 60% (0.3% TCH); 20% (0.1% TCH); 10% (0.05% TCH); |
- |
[100] |
|
OCT-loaded BNC |
OCT |
PBS, pH 7.4, 32 °C; 8 h: 82.7% ± 2.6% in first; 24 h 91.8% ± 2.0% after |
Ritger–Peppas model; n = 0.51–0.55; Non-Fickian diffusion. |
[101] |
|
PI-loaded BNC |
PI |
PI buffer, 32 °C; t84% = 48 h. |
Ritger–Peppas model; n = 0.608–0.612 |
[102] |
|
PHMB-loaded BNC |
PHMB |
PHMB buffer, 32 °C; t87% = 48 h. |
Ritger–Peppas model; n = 0.863–0.871 |
[102] |
Abbreviations: cCNC—Cationic cellulose nanocrystals; SA—Sodium alginate; CH—Ceftazidime hydrate; EGF—Epidermal growth factor human; PBS—Phosphate-buffered saline; CSos—Chitosan oligosaccharide; PrHy—Procaine hydrochloride; IMI—Imipramine hydrochloride; HDQ—Hydroquinone; C—Curcumin; CS—Chitosan; QC—Quaternized cellulose; β-GP—β-glycerophosphate; DOX—Doxorubicin; Gel—Gelatin; TPh—Theophylline; m-CNC—Magnetic cellulose nanocrystals; NIR—Near-infrared spectroscopy; PDA—Polydopamine; HPMC—Hydroxypropylmethyl cellulose; KT—Ketorolac tromethamine; Alg—Alginate; MH—Metformin hydrochloride; SGF—Simulated gastric fluid; SIF—Simulated intestinal fluid; HEPES—(4-(2-hydroxyethyl)-1-piperazine- ethanesulfonic acid); TCH—Tetracycline hydrochloride; AM—Acrylamide; Ibu—Ibupofren; OCT—Octenidine; PI—Povidone-iodine; PHMB—Polihexanide; dH2O—Distilled water.
NCs Type |
TE Systems |
Applications |
References |
---|---|---|---|
CNF |
CNF/CS nanocomposites |
Artificial skin |
[30] |
CNF-based thixotropic gels |
Breast cancer |
[50] |
|
Double crosslinking 3D-printed CNF hydrogels |
Skin TE |
[111] |
|
CNF/PVA bilayer scaffold |
Skin TE |
[115] |
|
CNF/Gel/ApA |
Bone TE |
[116] |
|
CNC |
CNC/PVA nanocomposites |
Skin TE |
[117] |
Gel/HA/CNC hydrogels |
Skin wound repair |
[118] |
|
Col/CNC/GMs |
Blood vessel |
[119] |
|
PEG-grafted CNC nanocomposites |
Bone TE |
[120] |
|
CNC/PVA hybrid hydrogels |
Soft TE |
[121] |
|
CNC/PAAm composite hydrogels |
TE |
[122] |
|
a-CNC/Gel hydrogels composite |
Breast cancer |
[123] |
|
TEMPO-CNC reinforced PVA hydrogels |
Corneal implant |
[124] |
|
BNC |
BNC/Fibrin composites |
New blood vessel |
[78] |
BNC-Gel/HAp nanocomposites |
Bone TE |
[125] |
|
Alg/BNC/Col composite |
TE |
[126] |
|
3D BNC/PMS scaffolds |
TE; soft tissues regeneration |
[127] |
|
DBC/Col-p |
TE; tissues regeneration |
[128] |
|
BNC/PA/Gel/HAp |
Bone repair |
[129] |
|
(BNC-Col)-Ap/OGP peptides |
Bone TE |
[130] |
|
BNC-CNTs composites |
Bone regeneration |
[131] |
|
BNC |
Ear cartilage TE |
[132] |
|
BNC/Alg bilayer composite |
Neocartilage formation |
[133] |
|
BNC/CS composites |
Cartilage tissue regeneration |
[134] |
Abbreviations: CS—Chitosan; PVA—Poly(vinyl) alcohol; Gel—Gelatin; ApA—Phosphonate; HA—Hyaluronic acid; Col—Collagen; GMs—Gelatin microspheres; PEG—Poly(ethylene glycol); PAAm—Polyacrylamide; a-CNC—Anionic CNC; HAp—Hydroxyapatite; Alg—Alginate; PMS—Paraffin microspheres; DBC—Dialdehyde bacterial cellulose; Col-p—Collagen peptide; PA—Procyanidin; Ap—Carbonate apatite; OGP—Osteogenic growth peptide; CNTs—Carbon nanotubes.
Material |
Cellulose Source |
Toxicological Experiment |
Cells Lines |
Toxicological Results |
Results and Possible Application |
Ref. |
---|---|---|---|---|---|---|
CNC |
||||||
CNC |
Cotton (Whatman 1 filter paper) |
MTS assay; ATP assay. |
BEAS 2B hMDMs |
Cytotoxicity at 100 mg/mL; No micronuclei induction after exposure to 2.5–100 mg/mL; No induction of proinflammatory cytokines in hMDMs. |
Toxicity impact on lungs or bone marrow |
[135] |
CNC CNC- carboxyl groups |
Softwood cellulose pulp |
MTS assay |
CaCO-2, HeLa, MDCK, J774 |
CNC not exhibit any significant cytotoxicity; can exert stress on cells if they possess a high charge density; Charge-dependent decrease in mitochondrial activity (charge contents > 3.9 mmol/g). |
Drug delivery |
[136] |
c-CNCs t-CNCs |
Cotton Tunicate from Stuela clava |
LDH assay |
A549 MDM MDDC |
The aspect ratio in combination with CNCs dose influences the uptake by the 3D co-culture system of the human epithelial airway barrier system. |
Toxicity impact on lungs |
[137] |
CNC |
Wood pulp |
TB assay |
A549 |
CNC were nontoxic to A549 cells; CNC induced a robust inflammatory response; CNC particles induced a more robust inflammatory response compared to NCF. |
Comparable toxicity of CNC with CNF |
[138] |
CNCgel CNCdry |
Wood pulp |
LDH assay |
MH-S |
Low conc. (1.5 and 5 μg/cm2) induce no cytotoxicity; A high dose of CNCdry induced a decrease in cell viability; CNC exposure further altered the secretion of cytokines. |
Toxicity impact on lungs |
[139] |
CNC |
Wheat bran |
MTT assay |
Caco-2 |
Dose-dependent decrease in cell viability, but only with significant results above 1000 μg/mL; The cell viability decreased significantly upon contact with CNC90 (88.09%) at 2000 μg/mL, although CNC30 (92.81%) and CNC60 (93.11%) did not significantly decrease the cell viability. |
Biocompatible nanocomposites |
[140] |
K-CNC R-CNC |
Rubberwood fiber Kenaf-bast fiber |
MTT assay |
RAW 264.7 HaCaT |
Cytotoxicity of K-CNC and R-CNC is not significant up to 700 μg/mL; K-CNC and R-CNC induced the formation of ROS in RAW264.7 macrophages. |
Biocompatible nanocomposites |
[141] |
CNC CNC-FL CNC-HM |
Cellulose pulp |
MTT assay |
ATCC PCS201012, A375 |
No cytotoxicity in direct and indirect contact assays. |
Drug delivery |
[142] |
CNC in nanocomposites |
||||||
Collagen/CNCs/ GMs scaffolds |
MCC |
MTT assay |
HUVECs |
No cytotoxicity; Excellent biocompatibility. |
Vascular TE |
[143] |
CNC CNC-AEM CNC-AEMA |
Softwood pulp |
ATP assay |
J774 A.1 PBMNC |
One cationic CNC induced secretion of proinflammatory cytokine IL-1b associated with increase mitochondrial-derived ROS and extracellular ATP levels. |
Drug and DNA delivery systems |
[144] |
PLA/CNCg-PEG nanocomposites |
Southern pine |
Live/dead assays |
hMSCs |
Suitable biocompatibility; Nontoxic effect on hMSCs proliferation. |
Bone TE |
[145] |
TEMPO-CNC reinforced PVA hydrogels |
MCC |
AB assay |
HCE-2cells |
Nontoxicity; Excellent biocompatibility; The HCE-2 cells viability above the 70%. |
Ophthalmic applications |
[146] |
PVA/CNC nanocomposites |
Sugarcane bagasse |
MTT assay |
L929 |
Noncytotoxic effect; Strong attachment and proliferation of human fibroblast skin cells on the scaffold. |
TE scaffolds |
[147] |
GA-HA-CNC hydrogels |
MCC |
CCK-8 assay |
NIH-3T3 |
Cell viability, at 1, 4, and 7 days, higher than 70% limit; No foreign body response. |
Skin TE |
[148] |
CS/Gel/NCC/CP nanocomposites |
Soft wood cellulose fibers |
MTT assay |
Fibroblast cell |
Lack of cytotoxicity after 3 days of increasing the cells’ viability. |
Wound healing |
[149] |
CNC/PVA |
MCC |
AB assay |
HCE-2 |
Nontoxic and cytocompatible profile of the CNC-PVA hydrogel; Suitable biocompatibility toward HCE-2. |
Ophthalmic applications |
[150] |
Abbreviations: BEAS 2B—Human bronchial epithelial cells; hMDMs—Monocyte-derived macrophages; Caco-2—Human colon carcinoma cells; HeLa—Human cervix; MDCK—Dog kidney; J774—Mouse macrophages; A549—Epithelial cells; MDM—Human blood monocyte-derived macrophages; MDDC—Dendritic cells; MH-S—Murine alveolar macrophages; RAW 264.7—Macrophages; ATCC PCS201012—Primary human fibroblasts; A375—Malignant melanoma cells; J774A.1—Mouse monocyte/macrophage; PBMNC—Peripheral blood mononuclear cells; hMSCs—Human mesenchymal stem cells; L929—Mouse fibroblast; NIH-3T3—Fibroblast; HCE-2—Human corneal epithelial cells; LDH assay—Lactate dehydrogenase cytotoxicity assay; MTT assay—(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay; TB assay—Trypan blue exclusion staining cell viability assay; MTS assay—CellTiter-Glo luminescent cell viability assay; MCC—Microcrystalline cellulose.
Material |
Cellulose Source |
Toxicological Experiment |
Cells Lines |
Toxicological Results |
Results and Possible Application |
Ref. |
---|---|---|---|---|---|---|
CNF |
||||||
CNF |
Bleached dissolving pulp Norway spruce (Picea bies) |
MTT assay [3H]-thymidine uptake assay |
L929; Thymocytes PBMNCs |
CNFs were not cytotoxic; CNC has non-inflammatory and on-immunogenic properties. |
Implantable biomaterials TE |
[151] |
CNF |
Pinus radiata pulp |
LDH assay MTT assay |
HEK NHDF |
No toxic effect for keratinocytes and fibroblasts; Non-immunotoxic. |
Wound dressings |
[152] |
CNF CNC |
Wood pulp |
TB assay |
A549 |
CNF caused a significant decrease in cell viability, at 72 h; Decrease in GSH levels after exposure to CNF. |
CNC toxicity |
[138] |
U-NFC A-NFC C-NFC |
Never-dried bleached sulfite softwood dissolving pulp |
AB assay LDH assays |
HDF MRC-5 THP-1 |
No cytotoxicity for treated NFC; HDF and MRC-5 cells: the metabolic activity of the treated cells was comparable to that of the negative control; THP-1 cells: a higher metabolic activity of the NFC-treated; U-CNF has an inflammatory response, which was suppressed when surface charges were introduced on the CNFs. |
Toxicity impacts on dermal, lung, and macrophage cells |
[153] |
CNF |
Bleached Eucalyptus Globulus kraft pulp |
MTT assay |
A549 THP-1 |
Cytotoxic effect at the highest dose tested; Genotoxic effects in A549 cells in the co-cultures; No oxidative DNA damages. |
TE |
[154] |
CNF |
Curauá fibers (Ananas erectifolius L. B. Smith) |
Cytotoxicity assays ISO 10993-5 |
Vero |
CNF shows no cytotoxicity and suitable biocompatibility; The morphology and basic functions of the cells are not affected by the direct contact with the tested materials. |
Scaffold TE |
[155] |
CNF |
Softwood bleached kraft fiber |
LDH assay |
Caco-2, HT-29MTX Raji B |
Minimal or no cytotoxicity in a cellular model of the intestinal epithelium (for CNC-25 at 0.75% and 1.5% w/w, as well as for CNF-50 at 0.75% w/w). |
Biocompatible material |
[156] |
CNF |
Banana peel bran |
MTT assay |
Caco-2 |
CNF conc. < 500 mg/mL are not cytotoxic to Caco-2 cells; Viability of Caco-2 decreased with increasing CNF conc. |
Biocompatible material |
[157] |
U-NFC A-NFC C-NFC P-NFC S-NFC |
Never-dried bleached sulfite softwood dissolving pulp |
Resazurin Assay |
Caco-2 |
None of the NFCs inducing cytotoxic effects in the intestinal cells; The differences in physics-chemical properties of the studied NFCs were not reflected in the Caco-2 response in terms of metabolic activity and cell membrane integrity. |
Drug release in gastrointestinal tract (GIT) |
[158] |
U-NFC C-NFC H-NFC P-NFC S-NFC |
Never-dried bleached sulfite softwood dissolving pulp |
MTS Assay |
BEAS-2B |
No cytotoxicity for the highest tested dose (500 μg/mL) for any of the NFCs; None of the NFCs induced genotoxic effects; All samples were able to increase intracellular formation of ROS. |
In vitro toxicity of NFCs |
[159] |
c-CNF cys-CNF |
Never-dried bleached sulfite softwood dissolving pulp |
PB assay |
hDF |
cys-CNF did not induce toxic effects on hDF when tested at a concentration up to 0.5 mg/mL, nor did the starting material c-NF cys-CNF presented a dual action in vitro: inhibition of metalloproteinase and radical scavenging activity. |
Wound dressing |
[160] |
CNF in nanocomposites |
||||||
CNF L-CNF CNC L-CNC |
Dissolving pulp |
AB assay |
A549 THP-1 |
Cytotoxic and inflammatory responses were dependent on type, size, and hydrophobicity Low or inexistent toxicity of all CNMs in A549 cells Dose-dependent cytotoxic and inflammatory responses in THP-1 cells. |
TE |
[161] |
CNF /GEL/ApA |
Bleached birch pulp |
MTT assay |
MSCs |
CNFs and CNF-COOHs have no cytotoxicity; CNF-COOH-ApA cells expressed a low level of stress, visible through lower cell density and the cell inclusions. |
Bone TE |
[162] |
NFC hydrogels crosslinked with Ca2+ |
Bleached sulfite softwood pulp |
AB assay |
hDF |
Cell viability about 78% indicates no toxic effects. No inflammatory response of blood-derived mononuclear cells was observed in relation to the cytokines secretion. |
Wound healing |
[163] |
TEMPO-CNF hydrogel |
Bleached birch kraft pulp |
MTT assay |
hDF |
Nontoxicity effect and great hDF cells viability. |
Wound healing |
[164] |
NFC/QCRs nanocomposites |
Brown algae |
MTT assay |
L929 |
Cells viability is higher than 80% (for 5 to 1000 μg/mL CNFs/QCRs), indicating that there is no cytotoxicity. |
Wound healing |
[165] |
Material |
Cellulose Source |
Toxicological Experiment |
Cells Lines |
Toxicological Results |
Results and Possible Application |
Ref. |
---|---|---|---|---|---|---|
BNC |
||||||
BNC scaffolds |
G. xylinus |
CCk-8 assay |
HUVECs, SMCs, Fibroblasts |
BC tubes have no toxic or side effects on vessel-related cells cultured on their surface; the surface of BC tubes was beneficial for cell attachment, proliferation, and ingrowth. |
Vascular TE |
[166] |
Octenidine-loaded BNC |
K. xylinus |
ATP assay |
HaCaT |
Pure BNC has no influence on HaCaT viability; OCT/BNC extracts exhibited time and concentration-dependent toxicity; cell-damaging effects were observed at extract conc >10% and longer incubation times (24 and 48 h). |
Active wound dressing |
[167] |
BNC |
Sugar cane molasses |
LDH activity |
HepG2/C3A |
BC is not cytotoxic (conc. < 170 μg/mL); BNC has a protective effect against CP-induced myelotoxicity and enotoxicity. |
Biomaterial TE |
[168] |
Vaccarin- loaded BNC |
G. xylinus |
MTT assay |
L929 |
BNC-Vac has lower toxicity and better biocompatibility than BNC; RGR for both BNC and BNC-Vac was above 74%. |
Wound dressing |
[169] |
Gentamycin-loaded BNC |
K. xylinus |
NR assay |
U2-OS |
No cytotoxicity on osteoblast culture after 24 h; gentamycin released from G-BNC after 8 h (400 mg/L) and 16 h (600 mg/L) is enough to eliminate S. aureus and P. aeruginosa biofilms. |
Bone regeneration TE |
[170] |
Curcumin- loaded BNC |
K. xylinus |
MTS assay |
HNDF |
The cytotoxic effect on the cells depended on the conc. of curcumin; at 0.5 mg/mL C, a strong cytotoxicity for BNC-C and BNC-DC180; BNC-DC300 suitable cytotoxicity, even at higher extract conc. |
Wound dressing |
[171] |
BNC-GTMAC BNC-GHDE |
G. xylinus |
AB assay |
HaCaT |
No cytotoxicity; Suitable wound closure rates in the presence of the samples, with complete coverage of the scratched area after 5 days. |
Wound dressing |
[172] |
BNC in nanocomposites |
||||||
BNC/ALG bilayer composites |
G. xylinus |
ISO10993-5:2009 |
hNCs hMNC |
The composites were found to be noncytotoxic, with a cell viability of 98% and a uniform distribution of cells on the entire porous layer. |
Neocartilage TE |
[173] |
BNC-COL-Ap composites |
G. xylinus |
MTT assay |
Osteoblastic cells |
The composites did not exhibit cytotoxicity effects. |
Bone regeneration TE |
[174] |
ALG/BCN/COL composite |
A. xylinum |
CCk-8 assay |
MC3T3-E1 hAMS |
MC3T3-E1 and hams cells were viable and proliferate well, after 2 and 5 days of incubation—suitable cytocompatibility. |
TE |
[175] |
BC-PHEMA composites |
A. xylinum |
AB assay |
rMSCs |
BC-PHEMA composites are nontoxic and biocompatible; did not influence the morphology and proliferation of the rMSCs. |
Wound dressing |
[176] |
BC/COL composites |
G. xylinus |
Live/ Dead assay |
UCBMSCs |
No cytotoxicity; Provide advanced microenvironment for UCB-MSCs viability and in vitro proliferation; Significantly elevated proteins and calcium deposition. |
Bone regeneration TE |
[177] |
GEL/BNC nanocomposite |
A. xylinum |
MTT assay |
HEK293 |
BNG showed negligible cytotoxicity. |
Wound dressing |
[178] |
BNC-GEL nanocomposite |
- |
MTS assay |
MRC-5 |
The samples have no cytotoxicity, and the cells retained their morphology in direct contact with the membrane, The cells attaching to the GEL porous site, while not attaching to the GEL thin-coated BC side. |
Bone regeneration TE |
[179] |
Chitosan-BNC |
K. xylinus |
MTT assay |
GM07492 |
No cytotoxicity for the BC group and BC-Chi-Cip group; Ciprofloxacin-loaded BC-Chi samples exhibited a significant but slight decrease in the metabolic activity of cells (moderate cytotoxicity). |
Wound dressing |
[180] |
GO/n-HAp/BNC/b-glucan biocomposite |
- |
NR assay |
MC3T3-E1 |
All samples had suitable potential for cell adhesion and proliferation with very low cytotoxicity The order of the cell viability: BgC-1.4 (93%) > BgC-1.3 (79.8%) > BgC-1.2 (71.4%) > BgC-1.1 (68.9%). |
Bone regeneration TE |
[181] |
Abbreviations: HUVECs—Human umbilical vein endothelial cells; SMCs—Smooth muscle cells; HaCaT—Human keratinocytes cells; HepG2/C3A—Human C3A hepatoma cells; L929—Mouse skin fibroblast cells; U2-OS—Osteoblast cell; HNDF—Human neonatal dermal fibroblasts; MC3T3-E1—Mouse osteoblastic cells; rMSCs—Mouse mesenchymal stem cells; UCBMSCs—Human umbilical cord blood-derived mesenchymal stem cells; MRC-5—Normal lung tissues cells; GM07492—Human fibroblast cells; CCk-8 assay—Cholecystokinin-octopeptide proliferation assay; ATP assay—Adenosine triphosphate assay; LDH assay—Lactate dehydrogenase assay; NR assay—Neutral red assay; MTS assay—CellTiter 96® Aqueous Non-Radioactive Cell Proliferation assay; AB assay—Alamar blue assay; G. xylinus—Gluconacetobacter xylinus; K. xylinus—Komagataeibacter xylinus; A. xylinum—Acetobacter xylinum; BNC- GTMAC—BNC functionalized with glycidyl trime-thylammonium chloride (GTMAC); BNC-GHDE—BNC functionalized with glycidyl hexadecyl ether (GHDE).